Re-Certification Course Spring 2018

Re-certification Course Spring 2018

Oklahoma’s First-response Information Resource System using Telecommunications

Photo by Eric Nguyen 2 OK-First Contact Information

Who Number Hours Best for:

Mesonet Operator (405) 325-3231 8:00a-7:00p Technical support and data operator@mesonet.org weekdays; issues 9:00a-12:00p weekends

James Hocker (405) 325-3230 8:00a-5:00p Questions, suggestions, or [email protected] weekdays comments about the OK-First program; technical support

Robert MacDonald (405) 325-2665 Portions of Questions about scheduling and (student) 8:00a-5:00p upcoming OK-First classes; [email protected] weekdays technical support; general information

Andrea Melvin (405) 325-2652 8:30a-5:00p Technical support; general [email protected] weekdays information

Brad Stanley (405) 325-5270 9:00a-5:00p Technical support [email protected] weekdays

OCS/Mesonet Main (405) 325-2541 8:00a-5:00p Tracking down answers and OK- Office weekdays First people!

Note: Voice mail for OCS Main Office and OCS staff is checked Monday-Friday only

After-Hours Emergencies (405) 364-6364 Data outages and issues outside (Pager) business hours

OK-First Social Media

Facebook: https://www.facebook.com/groups/okfirst/ (closed group; have to request access)

Twitter: https://twitter.com/okfirstmanager

Mesonet Social Media

3 National Weather Service Norman Critical Information Sheet

Mailing Address: National Weather Service 120 David L. Boren Blvd, Suite 2400 Norman, OK 73072

Website: weather.gov/norman

Twitter: twitter.com/NWSNorman Facebook: facebook.com/NWSNorman YouTube: youtube.com/NWSNorman

Spotter Report E-Mail: [email protected]

Main Phone: 405-325-3816 (can be given to public) Main Fax: 405-325-0901

UNLISTED – Do not distribute! 405-325-3659 (restricted to EM/public safety) or 800-275-1136

NWS Norman Management Team:

Meteorologist in Charge David Andra 405-325-3318 [email protected]

Warning Coordination Meteorologist Rick Smith 405-325-3395 [email protected]

Science and Operations Officer Todd Lindley 405-325-3527 [email protected]

National Weather Service Tulsa Critical Information Sheet

Mailing Address: National Weather Service 10159 East 11th Street, Suite 300 Tulsa, OK 74128

Administrative Phone: 918-832-4115 Administrative FAX: 918-832-4101 Unlisted Ops Phone: 918-832-4116 Public Forecast Line: 918-838-7838 (6am to 6pm)

UNLISTED EMERGENCY: 1-800-697-2636 (Restricted Access) SEVERE REPORTS ONLY: 1-800-722-2778 (Can be given to public)

Web Site: weather.gov/tulsa Spotter Report E-mail: [email protected]

Twitter: twitter.com/NWSTulsa Facebook: facebook.com/NWSTulsa Youtube: youtube.com/NWSTulsa

NWS Tulsa Management Team:

Meteorologist in Charge Steve Piltz 918-832-4132 (voice mail) [email protected]

Warning Coordination Meteorologist Ed Calianese 918-832-4133 (voice mail) [email protected]

Science and Operations Officer Steve Cobb 918-832-4115 x224 [email protected]

For contact information for additional National Weather Service offices visit:

http://www.stormready.noaa.gov/contact.htm

5 Using GOES-16 for Severe Storm and Wildfire Detection

http://rammb.cira.colostate.edu/ramsdis/online/images/loop_of_the_day/goes- http://cimss.ssec.wisc.edu/goes/blog/wp- 16/20170510000000/video/20170510000000_texas.gif content/uploads/2017/03/170307_goes16_shortwaveIR_KS_OK_TX_fires_a nim.gif

What We’ll Cover

1. Satellite Basics – How satellites work 2. GOES-R Series – About the series – Channels, resolution, and scanning modes 3. GOES-16 Applications – Severe storms – Wildfires 4. GOES-16 Data in OK-First

6 Learning Objectives

1. Form a basic understanding of how weather satellites work 2. Understand the improvements associated with GOES-R 3. Become familiar with several key GOES-R channels 4. Be able to identify key storm features in satellite products 5. Be able to identify wildfires in satellite products 6. Know where to find GOES-16 products in OK-First

Satellite Basics

7 Remote Sensing in Meteorology

• Remote Sensing – To measure something at a distance away from a sensor – Different from direct measurements, which are in contact with the object they are measuring (e.g., Mesonet, weather balloons, aircraft, dropsondes, etc.) • Remote Sensing Examples – Satellite – Radar – Lightning detection

2 Primary Types of Meteorological Satellites

• Polar Orbiting Satellites – Not fixed locations à circular, pole-ward orbit (~105 mins) – Orbit at low elevation (~500 miles) – Pros: higher data resolution; global coverage – Cons: cannot provide continuous viewing of same area • Geostationary Satellites – Fixed location over the equator – Higher elevation (22,300 miles) – Pros: observes the same area; high time resolution – Cons: coarser resolution (especially in polar regions)

8 https://www.youtube.com/watch?v=FsfcIEmR_b0

Global Satellite Observation System

https://www.meted.ucar.edu/tropical/textbook_2nd_edition/media/graphics/globalsys.jpg

9 How Do Weather Satellites Work?

• Measure electromagnetic radiation from surfaces below using radiometers – Weather satellites do not have cameras • Two kinds of radiometers – Imagers: measure radiation in the visible to infrared portions of the electromagnetic spectrum – Sounders: measure infrared radiation and provide vertical profiles of temperature, pressure, water vapor, and other trace gases • Data from radiometers are transmitted back to earth for image creation

Electromagnetic Spectrum

Weather satellite imagers measure in this region

http://cimss.ssec.wisc.edu/satmet/modules/3_em_radiation/emr-2.html

10 GOES-R Series

Next Generation NOAA Satellites: GOES-R Series

• GOES-R, GOES-S, GOES-T, and GOES-U – Extends operational GOES system through 2036 • GOES-R launched Nov 19, 2016 – Became GOES-16 in orbit & made operational on December 18, 2017 as the new GOES-East • GOES-S – Launch in 2018; will become GOES-17 & replace GOES-West • GOES-T – Launch anticipated in 2020 • GOES-U – Launch date TBD

11 NOAA Geostationary Satellite Programs Continuity of Weather Observations Calendar Year As of March 2017

09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

GOES-13 GOES East 60% Confidence

GOES-14 On-orbit spare 60% Confidence

GOES-15 GOES West 60% Confidence

GOES-16

Click on any bar for current status GOES-S GOES-13 GOES-T GOES-U Fiscal Year

09 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36

In orbit, operational Planned in-orbit Storage In orbit, storage Planned Mission Life Approved: ______Assistant Administrator for Satellite and Information Services Reliability analysis-based extended weather observation life estimate (60% confidence) for satellites on orbit for a minimum of one year -- Most recent analysis: March 2017

https://www.nesdis.noaa.gov/sites/default/files/asset/document/geostationary_weather_march_2017.pdf

GOES-East and GOES-West Locations

https://www.nasa.gov/sites/default/files/thumbnails/image/goes-r_fleet_new6.png

12 Instruments on GOES-R Series Satellites

https://www.meted.ucar.edu/satmet/satfc_g_course/rad_basics/media/graphics/goes_r_instruments_fc.jpg

Primary Weather Instruments on GOES-R Series

• Advanced Baseline Imager (ABI) – Primary instrument à views Earth with 16 channels • Geostationary Lightning Mapper (GLM) – First-ever operational lightning mapper in geostationary orbit à measures total lightning activity

https://www.goes-r.gov/spacesegment/abi.html

13 GOES-R Series Imager vs. Previous GOES Imager Technology • 3x More Channels – 16 channels compared to 5 – Includes: 2 Visible, 4 Near Infrared, and 10 Infrared channels • 4x Better Resolution • 5x Faster Scans – Full hemisphere every 15 minutes – Continental U.S. every 5 minutes – 2 mesoscale sectors every 30-60 seconds • 60x More Data from the Satellite – 1 terabyte of data per day!

What It Seems Like!

http://i.dailymail.co.uk/i/pix/2013/01/10/article-2259923- http://electronics.retailcatalog.us/products/3108353/large/49ug2500.jpg 16D752A6000005DC-519_634x503.jpg

14 Channels GOES-R Imager Wavelength On Previous Channel Nickname Channel (microns) GOES Imager? 1 0.47 “Blue” Visible No 2 0.64 “Red” Visible � 3 0.86 “Veggie” Near-Infrared (IR) No 4 1.378 “Cirrus” Near-IR No 5 1.61 “Snow/Ice” Near-IR No 6 2.25 “Cloud Particle Size” Near-IR No 7 3.90 “Shortwave Window” IR � 8 6.19 “Upper-level Water Vapor” IR � 9 6.95 “Mid-level Water Vapor” IR No 10 7.34 “Lower-level Water Vapor” IR No 11 8.5 “Cloud-top Phase” IR No 12 9.61 “Ozone” IR No 13 10.35 “Clean Longwave IR Window” No 14 11.2 “Longwave IR Window” � 15 12.3 “Dirty Longwave IR Window” No

16 13.3 “CO2” Longwave IR �

Channels

https://www.youtube.com/watch?v=6xfczXsEf1o

15 Recommended Channels

• Channel 2 – “Red” Visible – Daytime monitoring of clouds and smoke – Daytime monitoring of ice/snow cover when clear • Channel 7 – “Shortwave window” Infrared – Fire/hot spot detection • Channel 9 – “Mid-level water vapor” Infrared – Monitoring of mid-level features like troughs and ridges • Channel 13 – “Clean Longwave Infrared Window” – Day and nighttime monitoring of clouds

Resolution

Channels GOES-R Series Imager Previous GOES Imager 0.64 micron Visible 0.5 km ~1 km Other Visible/Near-IR Channels 1 km N/A Channels > 2 microns 2 km ~4 km

https://nasasport.files.wordpress.com/2017/03/imager_comparison.png

16 Faster Scans

Coverage GOES-R Series Imager Previous GOES Imager Full Disk Every 15 minutes Every 3 hours Continental U.S. Every 5 minutes Every ~15 minutes Mesoscale Sectors Every 30 or 60 seconds N/A

https://satelliteliaisonblog.files.wordpress.com/2017/04/20170402_vis_compare2_anno.gif

Faster Scans

https://www.nesdis.noaa.gov/sites/default/files/19sep17_maria_vis.mp4

17 Scanning Modes

• Multiple scanning modes available – Analogous to different scanning modes for radars • Flex Mode – Full disk every 15 mins – CONUS every 5 mins – 2 mesoscale sectors every 60 secs (or 1 every 30 secs) • Continuous Full Disk Mode – Full disk every 5 mins – Could be used when multiple high impact events are occurring simultaneously (e.g., volcanic eruption, tropical cyclone, and severe storms)

GOES-16 Applications

18 A Multitude of Applications

We’ll focus on these

Monitoring Severe Storms with GOES-16

• Higher resolution over both space and time helps to monitor a variety of features during storm lifecycle: – Pre-storm environment – Storm initiation – Mature severe storm – Storm dissipation • Key products to monitor: – Channel 2: Visible – Channel 13: Clean Longwave Infrared Window

19 Severe Storm Detection: New vs. Old

http://cimss.ssec.wisc.edu/goes/blog/wp- content/uploads/2017/05/170508_goes16_goes13_visible_Colorado_hail_storm_anim.mp4

Pre-storm Environment

• Features to look for… – Cumulus clouds – Towering cumulus (also called cumulus congestus) – Orphaned anvils – Boundaries

https://www.meted.ucar.edu/satmet/goes16_exercise/media/loops/congestus_orphans_wy_061 217_01/congestus_orphans_wy_061217_01.htm

20 Storm Initiation • Features to look for… – Rapid anvil development – Rapid cloud top cooling

https://www.meted.ucar.edu/satmet/goes16_exercise/navmenu.php?tab=1&page=2-0- 0&type=flash

https://www.meted.ucar.edu/satmet/goes16_exercise/navmenu.php?tab=1&page=3-2- 0&type=flash

21 https://www.meted.ucar.edu/satmet/goes16_exercise/navmenu.php?tab=1&page=3-2- 0&type=flash

Mature Severe Storm

• Features to look for… – Large, cold anvil with sharp edges near updraft – Overshooting top – Enhanced-V signature

22 Overshooting Top

• What is it? – Small area (less than 15 km) of extremely cold clouds protruding above the anvil • What causes it? – Very strong updraft – The updraft is so strong and the air has so much momentum that it briefly enters the stable layer atop the troposphere • Look for… – Visible: small area of “bumpy” clouds embedded in anvil – Infrared: extremely cold cloud tops embedded in the anvil

https://ssl.c.photoshelter.com/img-get/I00006R4L.JUlOQg/s/860/688/wsi-cld027a.jpg

23 Overshooting Top

https://www.meted.ucar.edu/satmet/goes16_exercise/navmenu.php?tab=1&page=2-0- 0&type=flash

Enhanced-V Signature • What is it? – A V-shaped region of colder cloud tops extending downwind from the storm updraft • What causes it? – A very strong updraft that acts like an obstruction and forces winds at the top of the troposphere around it – It is analogous to the “V-Notch” seen in radar reflectivity – A warm “wake” can be observed just downwind of the updraft • Look for… – A cold overshooting top, which forms the base of the Enhanced-V

24 Enhanced-V Signature

https://cimss.ssec.wisc.edu/snaap/enhanced-v/enh-v_fig2cw.png

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visi t/loops/16apr17/ir&loop_speed_ms=80

25 Other Features You May See at Times

• Low level inflow – lines of low clouds that feed into the updraft of a storm (usually from S or E) • Flanking line – organized lifting zone of cumulus and towering cumulus connected to a mature updraft

http://rammb.cira.colostate.edu/ramsdis/online/images/loop_of_the_day/goes- 16/20170516000000/video/20170516000000_storms.gif

Storm Dissipation

• Features to look for… – Loss of overshooting top and enhanced-V features – Warming cloud tops – Eroding anvil cloud shield

26 Storm Dissipation

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/8jun17/B02&loop_speed_ms=100%20

Storm Dissipation

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visit/loops/8jun17/B13&loop_speed_ms=100

27 Monitoring Wildfires with GOES-16

• Higher resolution over both space and time supports: – Earlier detection of fires – Detection of smaller fires • Hotter fires can be more accurately described – Due to a higher saturation temp (410K vs. 340K) • More accurate pixel locations – Greatly reduces “jumpiness” in animations • Key products to monitor: – Channel 7: Shortwave Window Infrared – look for hot spots – Channel 2: Visible – look for smoke plumes

Wildfire Detection Example 1: New vs. Old (Shortwave Window IR)

http://cimss.ssec.wisc.edu/goes/blog/wp-content/uploads/2017/03/170306- 07_goes16_goes13_shortwaveIR_KS_OK_TX_fires_anim.mp4

28 Wildfire Detection Example 2: New vs. Old (Shortwave Window IR)

http://cimss.ssec.wisc.edu/goes/blog/wp- content/uploads/2017/04/170411_goes16_goes13_shortwave_infrared_KS_fires_anim.gif

Wildfire Detection Example 2: New vs. Old (Visible)

http://cimss.ssec.wisc.edu/goes/blog/wp- content/uploads/2017/04/170411_goes16_goes13_visible_surface_visibility_KS_fires_anim.gif

29 Wildfire Detection Example 3 (2 visible, 1 IR)

Channel 1 (“blue” visible)

Channel 2 (“red” visible)

Channel 7 (“shortwave window” IR)

http://cimss.ssec.wisc.edu/goes/blog/wp- content/uploads/2017/04/170425_goes16_visible_shortwaveIR_GA_fires_zoom_anim.gif

GOES-16 Data in OK-First

30 GOES-16 Data in OK-First

• GOES-16 products are available in the OK-First Wx Briefing page under Wx Data à Satellite, including: – Visible (channel 2) – Mid-level water vapor (channel 9) – Clean longwave IR (channel 13) • Hot spot detection is available under Wx Hazard à Fire Weather – Shortwave window IR (channel 7) • Other good sources for viewing satellite products are provided as external links

GOES-16 Products on OK-First Wx Briefing

31 GOES-16 Products on OK-First Wx Briefing

Using GOES-16 for Severe Storm and Wildfire Detection Summary • Weather satellites are… – A remote sensing technology that measures radiation in the visible to infrared portion of the electromagnetic spectrum • The GOES-R series… – Consists of 4 geostationary satellites (R, S, T, and U) that will extend the lifespan of the GOES program through 2036 – Has 3x more channels, 4x more resolution, and 5x faster scans compared to previous satellites • GOES-16… – Is the new GOES-East satellite that covers Oklahoma

32 Using GOES-16 for Severe Storm and Wildfire Detection Summary • GOES-16 can be used in storm events to identify… – A variety of pre-storm, storm initiation, severe storm, and storm dissipation features in the visible and IR channels – Visible Channel: towering cumulus, anvils, overshooting tops, etc. – Clean Longwave Infrared Channel: Enhanced-V, overshooting tops, anvils, cloud temps, etc. • GOES-16 can be used in wildfire events to identify… – Smoke plumes in visible & hot spots in shortwave infrared • GOES-16 satellite products… – Are available via OK-First and other providers

References

• http://rammb.cira.colostate.edu/training/visit/training_sessio ns/basic_operations_of_abi_on_goes_r/ • http://rammb.cira.colostate.edu/training/visit/training_sessio ns/satfc_g_orientation/shymet/ • https://www.meted.ucar.edu/goes_r/abi/index.htm • https://www.meted.ucar.edu/satmet/goes16_exercise/index. htm • https://www.goes-r.gov/downloads/tri-brochure.pdf • https://www.goes-r.gov/spacesegment/abi.html • https://www.nasa.gov/content/goes-r/index.html • http://cimss.ssec.wisc.edu/goes/blog/ • http://rammb.cira.colostate.edu/training/visit/blog/

33 Cheat Sheets

Initiating and Mature Severe Storms GOES-16 Channel 2 – Visible Initiating storms

Anvil

Boundary with towering Orphan anvil cumulus Overshooting top

http://rammb.cira.colostate.edu/ramsdis/online/images/loop_of_the_day/goes- 16/20170518000000/video/20170518000000_ok.mp4

34 Initiating and Mature Severe Storms GOES-16 Channel 13 – Clean Longwave Infrared Window

Anvil Initiating storm

Overshooting Enhanced-V top

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=training/visi t/loops/16apr17/ir&loop_speed_ms=80

Dissipating Severe Storms

GOES-16 Channel 2 – Visible GOES-16 Channel 13 – Clean Longwave Infrared Window

Eroding anvil cloud shield Warming cloud tops

http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=trainin http://rammb.cira.colostate.edu/templates/loop_directory.asp?data_folder=trai g/visit/loops/8jun17/B02&loop_speed_ms=100%20 ning/visit/loops/8jun17/B13&loop_speed_ms=100

35 Fire Detection GOES-16 Channel 2 – Visible GOES-16 Channel 7 – Shortwave Window Infrared

Hot spots

Smoke plumes

http://cimss.ssec.wisc.edu/goes/blog/wp- content/uploads/2017/07/958x638_GOES16A_B27_G16_VIS_SWIR_CA _FIRES_08JUL2017_2017190_024718_0002PANELS.GIF

Questions?!

http://rammb.cira.colostate.edu/ramsdis/online/images/loop_of_the_day/goes-16/20170510000000/video/20170510000000_texas.gif

36 Radar Side Lobe Contamination

What Are Radar Side Lobes?

• Due to a weather radar’s imperfect radiation pattern, in addition to a “main lobe” of radiation there are also smaller ones called “side lobes”

Side lobes can occur in the vertical and horizontal directions

Side Lobe

37 Radiation Pattern of a Weather Radar

Main Lobe

(Doviak et al. 2000)

Side Lobe Contamination

• What we see on radar is dominated by radar returns from the main lobe

Side Lobe

38 Side Lobe Contamination

• But what if radar returns from a side lobe dominate the total signal? – Side lobe contamination

Side Lobe Updraft

More About Side Lobe Contamination

• Not a problem most of the time except when… – There are very sharp changes in reflectivity (vertically or horizontally) • Occurs most commonly in the inflow region of supercells due sharp reflectivity changes – Especially due to “reflectivity overhang” • What product is contaminated? – Velocity • What can it produce? – An erroneous area of rotation

39 More About Side Lobe Contamination

Is this where we would expect Rotation! to see rotation in a storm?

In this vertical cross section notice how an area of very high reflectivity is overhanging much lower reflectivity values near the ground.

Radar returns from the side lobe must be dominating the total signal à side lobe contamination in velocity at Tilt 1

Example 1: May 16, 2017 (Southwest OK)

Tilt 1 Tilt 1

Wow!

10-20 dBZ

Wait a minute… this seems to be in the wrong spot

Let’s look at reflectivity at higher tilts!

40 Example 1: May 16, 2017 (Southwest OK)

Tilt 2 Tilt 1

Example 1: May 16, 2017 (Southwest OK)

Tilt 3 Tilt 1

41 Example 1: May 16, 2017 (Southwest OK)

Tilt 4 Tilt 1

Looks like the velocity data at Tilt 1 was contaminated due to significant reflectivity at higher tilts à side lobe contamination!

~55 dBZ

Example 1: May 16, 2017 (Southwest OK)

Tilt 4 Tilt 1

“Reflectivity overhang” à a common cause of side lobe contamination

~55 dBZ 10-20 dBZ

42 Example 1: May 16, 2017 (Southwest OK)

Example 2: May 16, 2017 (Western OK)

Tilt 1 Tilt 1

Holy moly!

~20 dBZ

Right spot? Nope!

Let’s again look at reflectivity at higher tilts…

43 Example 2: May 16, 2017 (Western OK)

Tilt 2 Tilt 1

Example 2: May 16, 2017 (Western OK)

Tilt 3 Tilt 1

44 Example 2: May 16, 2017 (Western OK)

Tilt 4 Tilt 1

Side lobe contamination in base velocity Tilt 1 data due to very high reflectivity values aloft

60-65 dBZ

Example 2: May 16, 2017 (Western OK)

Tilt 4 Tilt 1

Check out that reflectivity overhang!

60-65 dBZ ~20 dBZ

45 Example 2: May 16, 2017 (Western OK) A little bit later…

Tilt 1 Tilt 1

Rotation in the proper location à no more side lobe contamination!

Example 2: May 16, 2017 (Western OK)

46 Radar Side Lobe Contamination Summary

• Side lobe contamination is… – The result of sharp gradients of reflectivity (hor. or vert.), which cause side lobe returns to dominate the total signal • Affects… – Velocity data • Most common in… – The inflow region of supercell storms • Things to watch for… – Blinky/noisy velocity values from scan-to-scan in storm inflow – If you see rotation, make sure it is in the “right spot” – If in wrong spot, check higher tilts to verify contamination

Acknowledgements A special thank you to Joey Picca (NWS Storm Prediction Center) and Vivek Mahale (NWS Norman) for providing materials that assisted in the development of this presentation!

Joey Picca, NWS SPC Vivek Mahale, NWS Norman

47 References

• Doviak, R. J., V. Bringi, A. Ryzhkov, A. Zahrai, and D. Zrnic, 2000: Considerations for Polarimetric Upgrades to Operational WSR-88D Radars. J. Atmos. Oceanic Technol., 17, 257-278.

Questions?!

48 Quasi-Linear Convective Systems (QLCSs)

What We’ll Cover

1. Introduction to QLCSs – What they are, typical hazards, where and when they are most common 2. QLCS Mesovortices – What they are, hazards they produce, tornadoes 3. Monitoring QLCSs with Radar – Bowing segments – Bookend vortices – Mesovortices – Inflow notches – Rear inflow notches

49 Learning Objectives

1. Become familiar with QLCSs and the hazards they typically produce 2. Understand what mesovortices are and what hazards they produce 3. Become familiar with different QLCS radar features to watch for in reflectivity and velocity

What’s with the Name QLCS?

• No, this isn’t about baseball… • Stands for Quasi-Linear Convective System – The popular scientific “catch all” term these days for squall lines, bow echoes, and other storms that resemble lines – Since many convective systems contain portions that are not very straight, “quasi-linear” has become the more flexible term to describe all of them

50 Examples of QLCSs

About QLCSs • Typical Hazards – Strong to severe wind gusts, very heavy rain, lots of lightning, and hail (commonly under 1 inch) • Less Common Hazards – Tornadoes (usually EF0-EF2) • Timing – Tend to occur in the late evening into overnight hours after storms have merged • Where do they occur most frequently in OK? – Eastern Oklahoma

51 Radar-Based Climatology of Oklahoma Squall Lines (1994-2003)

(Hocker and Basara 2008)

Radar-Based Climatology of Oklahoma Squall Lines (1994-2003)

Peak starting times (Hocker and Basara 2008) (~9p to ~1a)

52 QLCS Development

• QLCS formation: – Occurs when storm downdrafts combine to form a large pool of cool air at the surface • QLCS maturation: – The system grows in size with additional downdrafts increasing the size of the pool of cool air at the ground

https://en.wikipedia.org/wiki/Bow_echo #/media/File:Bow_echo_diagram.svg

53 QLCS Features

• Bow echo: A bow-shaped line of storms that produces strong winds • Bookend vortex: a circulation at the end of a line of storms • Rear inflow notch: reduced reflectivity due to the “rear inflow jet” • Mesovortices: small scale circulations on the leading edge Rear inflow notch

Possible Mesovortices

Bow echo https://en.wikipedia.org/wiki/Bow_echo #/media/File:Bow_echo_diagram.svg Bookend vortices

Cross-Section View of a QLCS

https://en.wikipedia.org/wiki/Rear-inflow_jet#/media/File:Ligne_de_grain.svg

54 QLCS Mesovortices

QLCS Mesovortices

• What are they? – Mesovortices are areas of rotation 1 to 12 miles in size that last for up to an hour and occur within the lowest 1 mile of the atmosphere (Weisman and Trapp 2003) • Where do they occur? – Along the leading edge of QLCSs, such as: • Along, north, or south of a bow echo apex • Inflow notch areas • Intersection of QLCS and outflow boundaries • Their impacts: – Can enhance straight-line winds at the ground – Sometimes produce brief tornadoes

55 Impacts of Mesovortices on Surface Winds

“rear inflow jet”

(Atkins and St. Laurent 2009)

QLCS Mesovortices and High Winds Go Together

• 95 mph at El Reno on 3/28/17 – 2nd highest Mesonet wind gust in 2017 • 87 mph at Copan on 4/26/16 – Probable mesovortex – 2nd highest Mesonet wind gust in 2016 • 99 mph at Red Rock on 11/17/15 – Highest Mesonet wind gust in 2015 • 106 mph at Burneyville on 7/30/14 – Highest Mesonet wind gust in 2014

56 Tornadoes from QLCS Mesovortices • Only some QLCS mesovortices produce tornadoes – More likely if there is tight/strong rotation on radar that can be seen on multiple tilts • Extremely rapid formation and short-lived – Mean lead time on radar of 5 minutes (Trapp et al. 1999) – Commonly persist for less than 10 minutes • Most commonly EF0-EF2 – Less than 5% of EF3-EF5 tornadoes are produced by non- supercells (Smith et al. 2012) • Occur on the leading edge of QLCSs

Monitoring QLCSs on Radar • Pro Tips: 1. View reflectivity and velocity together 2. Not sure if you see rotation? Check storm-relative velocity! 3. Expect features to change rapidly • Features to watch for: – Bowing segments • Associated with strong winds – Inflow notches on the leading edge of the QLCS • Could be indicative of an updraft and a mesovortex (verify in velocity) – Rear inflow notches on the back side of QLCS • Can lead to strong winds and mesovortex enhancement – Outflow boundaries

57 Monitoring QLCSs on Radar Example 1: Classic Bow Echo

Bow echo! Strongest winds

Bow Apex

Monitoring QLCSs on Radar Example 1: Classic Bow Echo

Inflow notches Mesovortices

58 Monitoring QLCSs on Radar Example 2: Strong Rear Inflow Jet

Bowing segment Very strong winds

Monitoring QLCSs on Radar Example 2: Strong Rear Inflow Jet

Inflow notch Mesovortex

Rear inflow notch Strong winds from rear inflow jet

59 Monitoring QLCSs on Radar Example 3: QLCS/Supercell Hybrid

Outflow boundary

Monitoring QLCSs on Radar Example 3: QLCS/Supercell Hybrid

Inflow notch

Outflow Tornadic boundary mesovortex

60 Additional Considerations from the NWS (from Vivek Mahale, NWS Norman)

• More mesovortices are detected today… – Due to super resolution radar, more frequent radar scanning, and airport radars (Terminal Doppler Weather Radars) • Additional wording can be used in warnings to highlight wind threat… – In the absence of strong gate-to-gate shear or a tornado debris signature, the NWS can convey enhanced wind damage potential and/or use the “tornado possible” tag in impact-based severe thunderstorm warnings and statements

November 17, 2015 Example

SEVERE WEATHER STATEMENT LOCATIONS IMPACTED INCLUDE... NATIONAL WEATHER SERVICE NORMAN OK STILLWATER...PONCA CITY...GUTHRIE...BLACKWELL...PERRY...TONKAWA... 207 AM CST TUE NOV 17 2015 PERKINS...NEWKIRK...LANGSTON...MORRISON...CARNEY...GLENCOE...TRYON. ..RIPLEY...KAW CITY...COYLE...CEDAR VALLEY...RED ROCK...MULHALL AND OKC071-081-083-103-119-170830- MARLAND. /O.CON.KOUN.SV.W.0653.000000T0000Z-151117T0830Z/ KAY OK-LOGAN OK-LINCOLN OK-NOBLE OK-PAYNE OK- PRECAUTIONARY/PREPAREDNESS ACTIONS... 207 AM CST TUE NOV 17 2015 REMAIN ALERT FOR A POSSIBLE TORNADO! TORNADOES CAN DEVELOP ...A SEVERE THUNDERSTORM WARNING REMAINS IN EFFECT UNTIL 230 QUICKLY FROM SEVERE THUNDERSTORMS. AM CST FOR KAY...LOGAN...NORTHWESTERN LINCOLN...NOBLE AND PAYNE COUNTIES... FOR YOUR PROTECTION MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A AT 206 AM CST...SEVERE THUNDERSTORMS WERE LOCATED ALONG A BUILDING. LINE EXTENDING FROM NEAR CHILOCCO TO NEAR SOONER LAKE TO NEAR && MERIDIAN...MOVING EAST-NORTHEAST AT 50 MPH. THE STRONGEST WINDS ARE EXPECTED TO BE ACROSS EASTERN KAY COUNTY... BUT LAT...LON 3678 9675 3674 9683 3675 9689 3668 9693 DAMAGING WINDS ARE POSSIBLE ALONG THIS ENTIRE LINE. 3668 9706 3659 9706 3660 9691 3658 9689 3651 9703 3633 9703 3633 9692 3625 9692 THESE ARE VERY DANGEROUS STORMS. 3624 9682 3574 9702 3573 9766 3642 9724 3698 9737 3700 9675 HAZARD...80 MPH WIND GUSTS. TIME...MOT...LOC 0806Z 256DEG 44KT 3697 9712 3640 9695 3584 9727

SOURCE...RADAR INDICATED. TORNADO...POSSIBLE HAIL...<.75IN IMPACT...FLYING DEBRIS WILL BE DANGEROUS TO THOSE CAUGHT WIND...80MPH WITHOUT SHELTER. MOBILE HOMES WILL BE HEAVILY DAMAGED. EXPECT CONSIDERABLE DAMAGE TO ROOFS...WINDOWS AND VEHICLES. EXTENSIVE TREE DAMAGE AND POWER OUTAGES ARE LIKELY.

61 Quasi-Linear Convective System (QLCS) Summary

• QLCSs are… – Squall lines and other storms that resemble lines – Accompanied by high winds, heavy rain, frequent lightning, and sometimes tornadoes – Most common in eastern Oklahoma – Commonly getting underway between 9p and 1a • Mesovortices are low level areas of rotation that… – Form at the leading edge of a QLCS – Can enhance straight-line winds at the surface – Sometimes produce tornadoes

Quasi-Linear Convective System (QLCS) Summary

• QLCS tornadoes… – Develop extremely rapidly – Are short lived – Are most commonly EF0-EF2s • QLCS features to watch for on radar: – Bowing segments – Bookend vortices – Mesovortices – Inflow notches on the leading edge – Rear inflow notches on the back side – Outflow boundaries

62 References

• Atkins, N. T., and M. St. Laurent, 2009: Bow Echo Mesovortices. Part 1: Processes That Influence Their Damage Potential. Mon. Wea. Rev., 137, 1514-1532. • Hocker, J. E., and J. B. Basara, 2008: A 10-year spatial climatology of squall line storms across Oklahoma. Int. J. Climatology, 28, 765–775. • Smith, B. T., R. L. Thompson, J. S. Grams, and C. Broyles, 2012: Convective modes for significant severe thunderstorms in the contiguous United States. Part I: Storm classification and climatology. Wea. Forecasting, 27, 1114-1135. • Trapp, R. J., E. D. Mitchell, G. A. Tipton, D. W. Effertz, A. I. Watson, D. L. Andra Jr., and M. A. Magsig, 1999: Descending and nondescending tornadic vortex signature. Wea. Forecasting, 24, 625-639. • Weisman, M. L., and R. J. Trapp, 2003: Low-level mesovortices within squall lines and bow echoes. Part II: Their genesis and implications. Mon. Wea. Rev., 131, 2804-2823.

63 Lab: Monitoring QLCS Events with Radar

Objective:

In this lab exercise we will investigate several different QLCS events and practice identifying different radar features including: bowing segments, mesovortices, inflow notches, rear inflow notches, and outflow boundaries.

Instructions:

You will need to use the latest version of RadarFirst to complete this lab. Please read each question carefully and answer them as best you can in the space provided. You are welcome to work on your own or in a group.

Note: The instructions in this exercise are for the Windows version of RadarFirst. The Mac version is similar but some functions (like short cuts) are not available. Please ask us if you have any questions.

Region of Focus for this Exercise:

The different parts of this lab exercise will focus on different locations. Follow the directions in each part closely.

Terminology:

The following are definitions of several terms relevant to this exercise:

• Base Reflectivity – Return signal to the radar that indicates the location and intensity of particles in the atmosphere such as rain, hail, snow, or other targets (such as bugs, buildings, trees, and other non-weather items). The more intense or reflective the ‘echo’, the higher the reflectivity value. • Base Velocity – Return signal to the radar indicating the velocity of a target toward or away from the radar beam. Much like a radar gun used in baseball, weather radar can only fully see targets moving directly toward or away from it. When winds become perpendicular to the radar beam, the radar can no longer see them. • Bookend Vortex – An area of rotation at the end of a QLCS. A bookend vortex on the northern end of a line typically rotates counterclockwise; the vortex on the southern end typically rotates clockwise. • Bow Echo – A bow-shaped line of thunderstorms that is often associated with swaths of damaging straight-line winds and sometimes tornadoes. • Fine Line – A subtle radar reflectivity feature that marks the location of fronts and boundaries (such as cold fronts, dry lines, and outflow boundaries). Fine lines are most

64 easily observed close to a radar since due to the low-level nature of fronts and boundaries. • Inflow Notch – A radar reflectivity feature associated with inflow into a thunderstorm that resembles a small bite taken out of the storm. • Mesovortex – An area of rotation 1 to 12 miles in size that lasts for up to an hour and occurs within the lowest 1 mile of the atmosphere. Mesovortices can enhance straight- line winds at the ground and sometimes produce brief tornadoes. • Outflow boundary – A surface boundary formed by the spreading out of thunderstorm- cooled air. These features appear in radar reflectivity as something called a “fine line.” • Quasi-Linear Convective System (QLCS) – A contiguous area of thunderstorms in a semi-linear orientation that is associated with heavy rain and high winds. The word quasi emphasizes that these systems do not have to be perfectly straight, but rather can be “kind of” straight. • Rear Inflow Jet – A relatively strong current of air that travels from the weaker precipitation area behind a QLCS towards the front. • Storm Relative Velocity – Similar to Base Velocity, except that it subtracts off the speed of the weather phenomena. This is particularly useful for diagnosing rotation in storms when they are moving very fast (such as 40+ mph) or when the rotation is weak.

RadarFirst Cheat Sheet:

• To zoom in – Double left mouse click, mouse scroll wheel, or finger pinch apart (touch screens only). Additional town names will appear as you zoom in. • To zoom out – Double right mouse click, mouse scroll wheel, or finger pinch together (touch screens only). Fewer town names will appear as you zoom out. • To pan the map – Click and drag with a left mouse click or finger touch and drag (touch screens only) • To change the date or time – At the top of the RadarFirst window click “Edit” and then “Date…”. From there you can change the date and time as needed. Click “Set Date” to apply your changes. (Short cut: Shift D) • To animate – At the bottom of the window click the large triangle for a 1-hour loop. If you would like to animate more than 1 hour click the “2” or “3” that appear further to the right. (Short cut: Space bar) • To change radar product – Next to the time at the top of the RadarFirst window click the abbreviated radar product name (such as “BREF1”) to open the product selection menu. From there click the product you need to view. • To change the radar site – At the top of the RadarFirst window click the radar site name (such as “KTLX – Oklahoma City”) to open the radar selection menu. From the map that appears you can select the radar you need to view. • To activate 2 panel mode – At the top of the RadarFirst window click “View” and then “Two Panes”. (Short cut: Shift 1 or 2)

65 Part 1: March 28, 2017 Event (Southwest and Central OK)

Open the RadarFirst software and change your site to the Frederick, OK radar (KFDR). Next, go to Edit à Date... (short cut Shift D) and change the date to 3/28/2017 and the time to 7:00 PM and then click Set Date. View the data in 2-pane mode (View à Two Pane or use short cut Shift 2). Make sure cities are visible on the map (Edit à Options… à Cities and Towns or use short cut Shift C). Load “BREF1” in the left pane and “BVEL1” in the right pane. Please hide Tornado, Severe Storm, and Flash Flood Warnings (Edit à Options… à uncheck Warnings or use short cut Shift W).

Question 1. Focus your attention on the line of storms in SW Oklahoma along the Red River. What do we call the storm feature in Base Reflectivity (left pane) just west of the radar (in Frederick, OK) that appears to stick out further? What hazard is usually associated with these?

Question 2. Hit the play button to animate radar data for 1-hour and watch the storms evolve. There is an interesting QLCS feature in Base Reflectivity that travels over Chillicothe, TX and then north and east towards Elmer, OK. What is it called? What do you see happening in Base Velocity where this feature is?

Stop the animation, change the time to 9:03 PM (Edit à Date…), and change your radar to Oklahoma City (KTLX).

Question 3. The bowing segment that was in SW OK at 7 PM is now near El Reno. At 9:03 PM what reflectivity feature do you see SW of El Reno (near Hinton)? What causes it?

Question 4. Looking at Base Velocity at 9:03 PM, what feature appears just to the NW of El Reno? What feature do you notice in Base Reflectivity at the same location?

66 Part 2: August 6, 2017 Event (Northeast Oklahoma)

Change your radar site to the Tulsa, OK (KINX) radar. Go to Edit à Date... (Short cut Shift D) and change the date to 8/6/2017 and the time to 1:15 AM. Make sure “BREF1” is in the left pane and “BVEL1” is in the right pane.

Question 5. Hit the play button to animate radar data for 1-hour (12:16 AM to 1:15 AM). What QLCS radar feature do you see in Base Reflectivity moving from Barnsdall to Ramona (north of Tulsa)? What are you seeing in Base Velocity over the same area?

Question 6. What QLCS feature develops in Base Reflectivity extending from Tulsa northward to Ramona? What hazard do these usually produce?

Pause the animation and change your time to 1:24 AM (Edit à Date...). Zoom in to Tulsa.

Question 7. The buttons on either side of the play button let you step forward and backward 1 frame at a time. Using these buttons and watching Tulsa, step through from 1:10 AM to 1:24 AM. What do you think you are seeing in Base Velocity tracking from central to SE Tulsa? What other radar product might help to see this feature more clearly?

Change your time to 1:45 AM and step frame-by-frame from 1:28 AM to 1:45 AM. Watch Base Velocity data from Talala, OK down the QLCS line to Inola, OK (the radar is located in Inola).

Question 8. How many mesovortices do you observe in this 17-minute period? What features do you notice in Base Reflectivity at the location of the mesovortices?

67 Part 3: October 21, 2017 (Southwest and Central Oklahoma)

Change your radar site to the Frederick, OK (KFDR) radar. Go to Edit à Date... (Short cut Shift D) and change the date to 10/21/2017 and the time to 7:00 PM. Make sure “BREF1” is in the left pane and “BVEL1” is in the right pane.

Question 9. Animate the radar data for 1-hour (6:01 PM to 7:00 PM) and watch the area of storms SW of OKC. What kind of storm (air mass, multicell, supercell) appears to be tracking from Medicine Park, OK to Apache, OK? Watch the storms SW of the Apache storm – what is happening to them by the end of the animation?

Change your radar site to the Oklahoma City, OK (KTLX) radar and your time to 8:00 PM (Edit à Date...) and animate for 1-hour (7:01 PM to 8:00 PM). Watch the storms SW of OKC.

Question 10. What subtle radar feature begins to show up ahead of the QLCS (near and NE of Rush Springs, OK) near the end of the animation?

Pause the animation and change your time to 9:05 PM (Edit à Date...). Step through one frame at a time (8:05 PM to 9:05 PM) and watch the storm that tracks over Norman, OK.

Question 11. It appears that there are two outflow boundaries that interact with the storm. At what time do you see the strongest rotation in Base Velocity? What do you notice about the outflow boundaries at that time?

Change your time to (Edit à Date...) 10:09 PM and animate for 1-hour (9:09 PM to 10:09 PM). Shift your attention to east of the OKC Metro area.

Question 12. What feature develops in Base Velocity and moves over Seminole, OK? What feature in Base Reflectivity appears in the same area?

68 QLCS Lab: Debrief and Answers

March 28, 2017 Event

Southwest and Central Oklahoma

69 Question 1: What do we call the storm feature just west of the radar that sticks out? What hazard is usually associated with these?

Bow echo! These are associated with strong winds.

Question 2: What QLCS feature moves from Chillicothe, TX to Elmer, OK? What is happening in Base Velocity?

Bookend Vortex

Broad area of rotation

70 Question 3: At 9:03 PM what reflectivity feature do you see SW of El Reno? What causes it?

Caused by rear inflow jet

Rear inflow notch

Question 4: Looking at Base Velocity at 9:03 PM, what feature appears just to the NW of El Reno? What feature appears in Base Reflectivity there?

Inflow notch Mesovortex

71 March 28, 2017 Storm Reports

Mesonet Data

72 Mesonet Data

Mesonet Data

73 Mesonet Data

Mesonet Data

74 Mesonet Data

August 6, 2017 Event

Northeast Oklahoma

75 Question 5: What QLCS radar feature do you see in Base Reflectivity moving from Barnsdall to Ramona? What are you seeing in Base Velocity?

Bookend Vortex

Broad area of rotation

Question 6: What QLCS feature develops in Base Reflectivity extending from Tulsa northward to Ramona? What hazard do these usually produce?

Bow echo! These are associated with strong winds.

76 Question 7: What do you think you are seeing in Base Velocity tracking from central to SE Tulsa? What other radar product might help to see this?

Mesovortex

Other product you could view à Storm Relative Velocity

Question 8: How many mesovortices do you observe in this 17-minute period? What features do you notice in Base Reflectivity?

333 444 3 4 3

2 2 2 2 2 5 5

1 1 1 1 1 1

77 March 28, 2017 Storm Reports

Tornado Tracks – Tulsa/Broken Arrow

78 Tornado Tracks – Tulsa/Broken Arrow

Tornado Tracks – Oologah

79 Tornado Summary

• 4 tornadoes – EF-2 in Tulsa – EF-1 in Broken Arrow – EF-1 in Oologah – EF-1 in Chelsea

October 21, 2017 Event

Southwest and Central Oklahoma

80 Question 9: What kind of storm appears to be tracking from Medicine Park to Apache? What is happening to the storms SW of the Apache storm?

Supercell!

Storms merging

Question 10: What subtle radar feature begins to show up ahead of the QLCS (near and NE of Rush Springs) near the end of the animation?

Outflow boundary

81 Question 11: At what time do you see the strongest rotation in Base Velocity? What do you notice about the outflow boundaries at that time?

Appear to intersect and get pulled into the storm updraft here

Strongest rotation at 8:36 PM

Question 12: What feature develops in Base Velocity and moves over Seminole, OK? What feature appears in Base Reflectivity at the same time?

Inflow notch

Mesovortex

82 October 21, 2017 Storm Reports

Some Closing Thoughts • Supercell events get more of the attention… – but QLCS events affect much larger areas • Key QLCS radar features to watch include: – Bow echoes – Bookend vortices and mesovortices – Inflow notches on front and rear side – Outflow boundaries • QLCS mesovortices – Develop and dissipate rapidly – Do NOT always produce tornadoes – Can produce wind damage that is hard to discern between straight-line and tornadic – May produce tornadoes that are not tornado-warned or have incredibly short lead times

83 Lightning!

What We’ll Cover

1. Lightning Basics – How it forms – Types 2. Lightning Detection – Ground based and satellites – Lightning climatology 3. Lightning Safety – Fatality stats, ways people are struck, medical impacts – Safety tips and common myths 4. Lightning Data in OK-First

84 Learning Objectives

1. Form a basic understanding of how lightning forms 2. Be able to name the different types of lightning 3. Become aware of the most common ways in which people are struck by lightning 4. Become very familiar with lightning safety tips and common myths 5. Understand how lightning is displayed in OK-First tools

Lightning Basics

85 What is Lightning?

• Simple definition: – A giant spark of electricity in the atmosphere between clouds, the air, or the ground • Technical definition: – The series of electrical processes taking place by which charge is transferred along a discharge channel between electric charge centers of opposite sign

Bottom line: Lightning is the result of a build up of opposing electrical charges. Lightning exists to re- establish charge equilibrium (albeit briefly)!

You’ve experienced small scale “lightning” before (Stop dragging those feet on the carpet!)

Before zap After zap

Image Source: http://mrcc.isws.illinois.edu/living_wx/lightning/StaticElectricity.png

86 So How Do Storms Get Opposing Charges?

• Precipitation theory: – Updraft causes a collision between graupel (also called “soft hail” or “snow pellets”) and smaller ice/snow crystals which results in charge separation – Heavier particles acquire – charge – Lighter particles acquire + charge Image Source: https://upload.wikimedia.org/wikipedia/common • Convection theory: s/6/61/Graupel_animation_3a.gif – Updrafts transport positive charge found near the ground – Downdrafts transport negative charges downward

Conceptual Model of Electrical Charge in T-Storms

Image Source: http://www.nssl.noaa.gov/education/svrwx101/lightning/img/tstm- lightning-structure-800.png

87 The Result of Charge Separation: An Electric Field

• The separation of positive and negative charges creates an electric field – Continued charge separation strengthens the electric field • Air is an excellent electrical insulator – Which means that electricity does not flow freely within it – So tremendous amounts of charge have to be built up before lightning can occur • But once a charge threshold is reached… – The electric field overpowers the air’s insulating properties and we get lightning

Lightning Types

• Cloud-to-ground (CG) – Approximately 20% of lightning • In-cloud (IC) • Cloud-to-cloud (CC) • Cloud-to-air (CA)

88 Cloud-to-ground (CG)

Image Source: http://ngm.nationalgeographic.com/wallpaper/img/2012/08/12- ground-fire-ignited-by-lightning_1600.jpg

In-cloud (IC)

Image Source: http://travel.nationalgeographic.com/u/TvyamNb- BivtNwcoxtkc5xGBuGkIMh_nj4UJHQKuoXI5LoZHrdV9Ze5CIgWzS4a_e-bwZBEtNVNmMA/

89 Cloud-to-cloud (CC)

Image Source: http://ngm.nationalgeographic.com/wallpaper/img/2012/08/05- horizontal-cloud-to-cloud-lightning_1600.jpg

Cloud-to-air (CA)

Image Source: http://www.nssl.noaa.gov/education/svrwx101/lightning/types/img/IMG_0200.jpg

90 Cloud-to-ground Lightning: How Does it Happen?

• Step 1: – The collection of charge at the bottom of the cloud causes a pool of positive charge to collect along the ground – This positive charge travels with the storm as it moves

Image Source: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Cloud-to-ground Lightning: How Does it Happen?

• Step 2: – As the electric field strengthens a channel of negative charge descends from the bottom of the storm toward the ground – this is called a “stepped leader” – Meanwhile positive charge begins to rise from the ground, particularly from taller objects

Image Source: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

91 Cloud-to-ground Lightning: How Does it Happen?

• Step 3: – Positive charge from the ground begins extending upward towards the approaching stepped leader – these are called “streamers” – When the stepped leader and streamer connect (usually 30-50 m above ground) lightning occurs – After the initial stroke if enough charge remains, additional strokes will occur on the same channel, which can cause flickering

Image Source: http://www.srh.noaa.gov/jetstream/lightning/lightning.html

Stepped Leaders and Streamers: A Closer Look

Streamers Stepped leader

Image Source: http://www.srh.noaa.gov/jetstream/lightning/lightning_max.html

92 A Connection is Made: The Return Stroke

Image Source: http://www.lightningsafety.noaa.gov/science/science_return_stroke.shtml

Lightning Development in Super Slow Motion

Open “6.1_Slow_Motion_Lightning_Animation.mov”

93 Negative vs. Positive Lightning Strikes

• Lightning can be positively or negatively charged – If lightning transfers – charge from one location to another it is negative lightning – If lightning transfers + charge from one location to another it is positive lightning • Most C-G strikes are negative lightning – Peak current averages 30,000 amps (can be as high as 120,000 amps) • Positive lightning is less common but very powerful – Approximately 5-10% of lightning strikes – Peak current of 300,000 amps

Remember This?

One region where positive lightning initiates

One region where negative lightning initiates

Image Source: http://www.nssl.noaa.gov/education/svrwx101/lightning/img/tstm- lightning-structure-800.png

94 Image Source: http://images.nationalgeographic.com/wpf/media- live/photos/000/208/custom/20849_1600x1200-wallpaper-cb1275419114.jpg

Lightning Detection

95 How is Lightning Detected

• Ground-based detection systems – Earth Networks Total Lightning Network and Vaisala National Lightning Detection Network (U.S. networks) – Use network of sensors that detect high-frequency radio signals (in the VHF band) emitted by lightning – Triangulation used to determine location of lightning • Satellite-based detection systems – New U.S. GOES-R satellite has a Geostationary Lightning Mapper (GLM) – The GLM detects lightning using a single-channel, near- infrared optical detector – Detects total lightning – it cannot distinguish CG, IC, and CC

How is Lightning Detected

Image Source: http://www.geek.com/wp-content/uploads/2014/06/lightning- 625x350.jpg

96 Lightning Climatology

Image Source: https://upload.wikimedia.org/wikipedia/commons/c/c5/Global_lightning_strikes.png

Lightning Climatology

Image Source: Email correspondence with Melanie Scott ([email protected] )

97 Lightning Safety

Lightning in the United States: By the Numbers (Based on 2006-2015 averages)

• Lightning strikes ~25 million times each year • Lightning kills an average of 31 people each year • Lightning injures 279 people each year – So roughly 90% of those that experience a strike in some form survive • Lightning kills more males (79%) than females (21%) • Odds of being struck in any given year: 1 in 1,042,000 • Odds of being struck in a lifetime: 1 in 13,000

98 Image Source: http://www.lightningsafety.noaa.gov /slideshows/Lightning%20Safety%20 Statistic%20Graphics16.pptx

Image Source: http://www.lightningsafety .noaa.gov/slideshows/Light ning%20Safety%20Statistic %20Graphics16.pptx

99 Image Source: http://www.lightningsafety.noaa.g ov/slideshows/Lightning%20Safety %20Statistic%20Graphics16.pptx

Lightning Fatalities (By State)

Image Source: http://www.lightningsafety.noaa.gov/light- images/15deaths_bystatemap.png

100 Lightning Fatalities (By Year)

Image Source: https://www.washingtonpost.com/news/capital-weather- gang/wp/2015/07/09/lightning-deaths-year-to-date-are-the-highest-theyve-been- since-2007/?utm_term=.32c36eda723b

Lightning Fatalities (By Year and Gender)

Image Source: http://www.cdc.gov/mmwr/preview/mmwrhtml/figures/m6228qsf.gif

101 Understanding the Threat

Image Source: http://www.lightningsafety.noaa.gov/animations/Animation%2031a.gif

The Five Ways Lightning Strikes People

• 1. Direct strike: – 3 to 5% – Very uncommon!

Image Source: http://www.lightningsafety.noaa.gov/struck.shtml Image Source: http://i.imgur.com/izG6E7L.jpg

102 The Five Ways Lightning Strikes People

• 2. Side flash: – 30 to 35%

Image Source: http://www.lightningsafety.noaa.gov/struck.shtml Image Source: http://images.fineartamerica.com/images/artworkimages/mediuml arge/1/a-lightning-scarred-tree-in-a-forest-taylor-s-kennedy.jpg

The Five Ways Lightning Strikes People

• 3. Ground current: – 50 to 55% – Most common!

Image Source: Image Source: http://www.lightningsafety.noaa.gov/struck.shtml http://nols.blogs.com/.a/6a00d83451b4f069e20177445e975c970d-pi

103 The Five Ways Lightning Strikes People

• 4. Conduction/contact voltage: – 3 to 5%

Image Source: http://www.lightningsafety.noaa.gov/struck.shtml Image Source: http://www.thelivingmoon.com/45jack_files/04images/Biolog y/Dead_Cows_Fence1.jpg

The Five Ways Lightning Strikes People

• 5. Upward streamer: – 10 to 15%

Image Source: http://www.lightningsafety.noaa.gov/struck.shtml Image Source: https://pbs.twimg.com/media/CJpBO_XVEAAjX2X.png

104 Medical Impacts of Lightning

• Death due to cardiopulmonary arrest • Injuries to nervous system • Short-term issues: – Muscle soreness – Headache, nausea, dizziness, balance problems • Longer-term issues (not all): – Irritability and personality change – Chronic pain from nerve injury – Headaches and ear/balance problems – Memory issues – Sleep issues

Lightning Victims

Image Source: http://ichef.bbci.co.uk/news/1024/media/images/69194000/jpg/_69194715_624_lightning-burn.jpg

105 Lightning Safety Tips – Outdoors

• There is NO safe place outside when thunderstorms are in the area – Make a lightning safety plan – Have a way to get up-to-date weather information – Have a safe place to get to: an enclosed building or a vehicle • If you absolutely cannot get to safety… – Avoid open fields and hill tops – Avoid isolated tall objects (towers, poles, trees, etc.) – If in a group – spread out to avoid ground current – Stay away from water, wet items, and metal

Image Source: http://www.lightningsafety.noaa.gov/ signs/thunder_roars.jpg

106 Lightning Safety Tips – Indoors

• Safe shelters are: – Buildings with electricity and/or plumbing – Metal-topped vehicle with windows closed • Unsafe structures: – Picnic shelters, dugouts, small buildings without plumbing/electricity • When in a safe shelter… – Stay off corded phones – Don’t touch electrical equipment (computer, tv, cords) – Stay dry – do not wash hands, take shower, etc. – Stay away from windows and doors

Common Lightning Myths

• Myth: Lightning never strikes the same place twice – Fact: Lightning strikes many tall objects multiple times • Myth: Rubber tires on a car protect you from lightning – Fact: Your car’s metal roof is what keeps you safe • Myth: A lightning victim can electrocute you – Fact: It is safe to touch a lightning victim • Myth: If caught out in a storm, crouching reduces risk – Fact: Crouching doesn’t make you any safer. You are not safe anywhere outside! • Myth: If caught in a storm lay flat on the ground – Fact: Laying flat increases potential of deadly ground current

107 Lightning Data in OK-First

Lightning Data in RadarFirst/Wx Briefing

• About OK-First’s lightning data – Provider: Weather Decision Technologies – 1-minute data • Lightning data is displayed as – or + icons – Minus icons denote negative strikes – Plus icons denote positive strikes • Cloud-to-ground (CG) strikes shown differently – CGs will appear as – or + icons with a circle around them – All other strike types (in-cloud, cloud-to-cloud, cloud-to-air) will appear only as – or + icons • Higher amperage strikes are larger icons

108 Lightning Data in RadarFirst

• Two ways to display lightning data: – In the preferences: Go to “Edit” à “Options…” and check lightning – Keyboard shortcut: Hold “Shift” and press “L”

Lightning Data in RadarFirst

Because lightning can clutter the map it will only appear in the left pane when in 2-pane mode

109 Lightning Data in RadarFirst

To quickly turn lightning off and on use “Shift L”

Lightning Data in Weather Briefing Lightning data available in the Radar Console and Combo products

110 Lightning Summary • Lightning is the result of… – Charge separation in thunderstorms caused by the collision of precipitation particles above the freezing level • Lightning types include… – Cloud-to-ground, in-cloud, cloud-to-cloud, and cloud-to-air • Lightning can be… – Positively or negatively charged • Detection methods include… – 1) Ground-based systems that measure high frequency radio signals and 2) satellite-based methods that measure optical changes

Lightning Summary • Lightning fatalities in the United States… – Average 31 people per year – Comprise more males (79%) than females (21%) • Lightning strikes people in the following ways… – Ground current (most common), side flash, upward streamer, conduction, and direct strike (least common) • Regarding lightning safety… – NO place outside is safe from lightning – Metal-topped vehicles & buildings w/ electricity are safest – When thunder roars, go indoors!! • Lightning data is in RadarFirst and Weather Briefing

111 Some Excellent Resources on Lightning

• http://www.lightningsafety.noaa.gov/ • http://www.srh.noaa.gov/jetstream/lightning/lightning_intro. html • http://www.nssl.noaa.gov/education/svrwx101/lightning/ • http://mrcc.isws.illinois.edu/living_wx/lightning/index.html

112 GOES-16 Band Reference Guide [email protected]

ABI Band #1 ABI Band #2

0.47 microns 0.64 microns

Visible (“Blue Band”) Visible (“Red Band”)

Primary Uses: Primary Uses:

 Monitoring aerosols (smoke, haze, dust)  Daytime monitoring of clouds (0.5-km spatial resolution)  Air quality monitoring through measurements of aerosol optical depth  Volcanic ash monitoring

ABI Band #3 ABI Band #4

0.86 microns 1.37 microns

Near–IR (“Veggie Near-IR (“Cirrus Band”) Band”) Primary Uses: Primary Uses:

 High contrast between water and land  Thin cirrus detection during the day as the lower  Assess land characteristics including flooding troposphere is not routinely sensed impacts, burn scars, and hail swath damage  Volcanic ash monitoring

ABI Band #5 ABI Band #6

1.6 microns 2.24 microns

Near–IR (“Snow/Ice Near-IR (“Cloud Par- Band”) ticle Size Band”) Primary Uses: Primary Uses:

 Daytime snow, ice, and cloud discrimination  Cloud particle size, snow, and cloud phase (Snow/Ice dark compared to liquid water clouds)  Hot spot detection at emission temperatures of  Input to “Snow/Ice vs. Cloud” RGB greater than 600K

ABI Band #7 ABI Band #8

3.9 microns 6.2 microns

IR (“Shortwave IR (“Upper- Window Band”) Troposphere WV

Contains daytime solar reflectance component In a standard US atmosphere the weighting function peaks around 340 mb. **NOTE: The sensed radiation is Primary Uses: from a layer, not just the peak pressure level which  Low stratus and fog (especially when differenced itself varies from the standard value with the 11.2-micron IR channel taking advantage Primary Uses: of emissivity differences)  Upper-level feature detection (jet stream, waves,  Fire/hot spot detection and volcanic ash etc.) 113 ABI Band #9 ABI Band #10

6.9 microns 7.3 microns

IR (“Mid-Level Tropo- IR (“Low-Level Trop- sphere WV Band”) osphere WV Band”) In a standard US atmosphere the weighting function In a standard US atmosphere the weighting function peaks around 440 mb. **NOTE: The sensed radiation is peaks around 615 mb. **NOTE: The sensed radiation is from a layer, not just the peak pressure level which from a layer, not just the peak pressure level which it- itself varies from the standard value self varies from the standard value Primary Uses: Mid-level feature detection Primary Uses: Low-level feature detection (EML, fronts)

ABI Band #11 ABI Band #12

8.4 microns 9.6 microns

IR (“Cloud-Top Phase IR (“Ozone Band”) Band”) Primary Uses: Primary Uses:  Dynamics near the tropopause including strato-  Cloud-top phase and type products derived when spheric intrusions (high ozone) associated with combined with the 11.2- and 12.3- micron channels cyclogenesis. PV anomaly applications  Volcanic ash (S02 detection) and dust  Input to Airmass RGB

ABI Band #13 ABI Band #14

10.3 microns 11.2 microns

IR (“Clean IR IR (“IR Longwave Longwave Band”) Band”)   Less sensitive to atmospheric moisture than the oth- The traditional IR window er IR channels. As a result brightness temperatures  Differenced with the 3.9 micron near IR channel for are usually warmer than traditional IR as less radia- low stratus and fog detection tion is absorbed by water vapor and re-emitted at higher altitudes

ABI Band #15 ABI Band #16

12.3 microns 13.3 microns

IR (“Dirty IR IR (“C02 Longwave Longwave Band”) IR Band”)  Greater sensitivity to moisture compared to the 10.3- Primary Uses: and 11.2-micron channels. As a result, brightness  Mean tropospheric air temperature estimation temperatures will be cooler  Input to RGBs to highlight high, cold, and likely  Contributes to total PWAT and low-level moisture icy clouds information

Useful Links:

 Individual ABI Band Guides: http://www.goes-r.gov/education/ABI-bands-quick-info.html

 ABI Weighting Function Page: http://cimss.ssec.wisc.edu/goes/wf/ABI/ 114

RadarFirst Cheat Sheet For Version 1.7, January 2017 (Note: RadarFirst 1.7 is Windows Only) Using the Map • To move the map: o [Mouse] Left mouse click, hold, and drag o [Touch screen] Finger touch and drag across the screen • To zoom the map in: o [Mouse] Double left mouse click OR mouse scroll wheel o [Touch screen] Finger pinch apart • To zoom the map out: o [Mouse] Double right mouse click OR mouse scroll wheel o [Touch screen] Finger pinch together • To animate the map: o Click the play button in the black bar at the bottom (default: 1-hour animation). For 2- or 3-hour animations click “2” or “3” at the bottom right (animation start/stop short cut: space bar) • To view data in one or two panes: o Go to View à One Pane or View à Two Panes (short cut: Shift 1 or Shift 2) • To view more than one radar site: o Open the RadarFirst software additional times and view different radars on each

Changing Radar Sites/Products • To change a radar site: click the radar name (e.g. KTLX – Oklahoma City) in the black bar that appears near the top. Click any 3 letter radar identifier to change radars. Drag the map to see and select additional radars. • To change a radar product: click the radar product name (e.g., “BREF1”) in the black bar near the top and then click any radar product to change to it. For products with multiple tilts (e.g., BREF1, 2, 3, 4) only click the number.

Changing Options • To change RadarFirst options: go to Edit à Options… (short cut: Shift O) • Options include showing/hiding different map elements (e.g., cities, storm tracks, lightning, etc.), setting up audible alerts for counties of your choosing, proxy server settings, and graphics settings

Changing the Date • To change the time/date: go to Edit à Date… (short cut: Shift D) • Note: radar is only available for a limited set of events. Changing the time/date and seeing nothing means we do not have radar data archived for that particular event.

Short Cuts • A total of 11 “hot key” short cuts are available in the software, including: 1. Animation start/stop: Space bar 7. City names shown/hidden: Shift C 2. Date: Shift D 8. Storm warnings shown/hidden: Shift W 3. Options: Shift O 9. Storm tracks shown/hidden: Shift T 4. One pane mode: Shift 1 10. Spotter locations shown/hidden: Shift P 5. Two pane mode: Shift 2 11. Lightning shown/hidden: Shift L 6. Snapshot: Shift S (saves images to “Pictures” folder)

Hidden Features • To return to Oklahoma in the radar product selector window: right mouse click within the window • To change color scale on BREF, BVEL, or SRVEL products: right mouse click while mouse cursor is over the color bar at the bottom. Additional right clicks will return to the original color scale. 115