TheTheThe NationalNationalNational OceanicOceanicOceanic andandand AtmosphericAtmosphericAtmospheric AdministrationAdministrationAdministration (NOAA)(NOAA)(NOAA)

PresentsPresents

NationalNational WeatherWeather ServiceService (NWS)(NWS)

SevereSevere ThunderstormThunderstorm ObservingObserving andand RadarRadar MonitoringMonitoring

Severe Weather Spotter Line – 1-888-668-3344 Spotter Reports E-mail: espotter.weather.gov Homepage Address: weather.gov ObjectivesObjectives

• Understand Severe Weather Terms and Definitions • Learn basic ingredients needed for thunderstorms • Be able to identify different thunderstorm types • Know the dangers of each storm type and what safety actions to take when first identified •Improve Public Safety at your facility!! SevereSevere WeatherWeather JoeJoe SaysSays……

I am all eyes and ears, lets begin! FundamentalFundamental DefinitionsDefinitions

•• WarningWarning - Issued when a particular severe weather hazard is either imminent or is occurring. Take immediate action to protect life and property. •• WatchWatch - Issued when conditions are favorable for a particular severe weatweather hazard to occur in the next several hours. Plan, prepare, and be aware. FundamentalFundamental DefinitionsDefinitions •• ThunderstormThunderstorm – A local storm produced by a cumulonimbus cloud and always accompanied by lightning and thunder, usually with strong gusts of wind, heavy rain and sometimes hail.

We do not issue warnings for lightning. Take shelter when you first hear thunder! Don’t take a chance! FundamentalFundamental DefinitionsDefinitions WhatWhat MakesMakes aa ThunderstormThunderstorm Severe?Severe?

•• Tornado •• Winds at least 58 mph or reports of damage •• Hail at least ¾ inch in diameter •• Flash Flooding North Webster, IN October 24, 2001 Peru, IN July 15, 2003 Aurora, NE June 22, 2003 FundamentalFundamental DefinitionsDefinitions •• TornadoTornado -- A violent rotating column of air in contact with the ground, either pendant or underneath a cumuliform cloud. FundamentalFundamental DefinitionsDefinitions

•• FunnelFunnel CloudCloud - A violently rotating column of air that does not reach the ground. No circulation is seen on the surface. FundamentalFundamental DefinitionsDefinitions •• RotatingRotating WallWall CloudCloud - An isolated lowering from a cumulonimbus cloud base. – Must be rotating – May resemble a pedestal – Often precede funnel cloud and tornado FundamentalFundamental DefinitionsDefinitions •• ShelfShelf oror RollRoll CloudCloud - Low level, horizontal, wedge shaped cloud occurring on leading edge of a thunderstorm. Wind, rain and hail may follow, but may not be severe. FundamentalFundamental DefinitionsDefinitions •• Scud Clouds - Ragged edge clouds that do not rotate and are located below the main cloud base. May move “up and into” cloud below an updraft

Millersburg, Indiana – Elkhart County SevereSevere WeatherWeather JoeJoe SaysSays……

That was interesting, but can you tell me how thunderstorms develop and why they can become severe? CluesClues toto ThunderstormThunderstorm DevelopmentDevelopment

•• MoistureMoisture – Hazy, humid days, monitor dew points (60s and 70s) – Low clouds in the morning

•• InstabilityInstability ((Will the air rise) – Once cumulus clouds show up...look for rapid – Growth/development

•• TriggerTrigger oror focusingfocusing mechanismmechanism – Fronts, lake breezes, Outflow Boundaries from other thunderstorms – Afternoon heating

•• ShearShear – Wind shifts/Strong winds – Clouds at different levels moving different directions CluesClues toto ThunderstormThunderstorm DevelopmentDevelopment Classic Weather Map SimpleSimple ThunderstormsThunderstorms WeakWeak shear,shear, limitedlimited moisturemoisture

Developing Stage -Tall cumulus clouds develop -Little or no rain initially -Lightning begins as ice develops

Mature Stage - Hail, heavy rain, frequent lightning, strong winds, and isolated tornadoes

Dissipating Stage - Rainfall decreases - Downburst of strong winds -Lightning remains a danger SimpleSimple ThunderstormsThunderstorms Weak shear, limited moisture and Instability

Nearly Vertical Updraft/Downdraft Radar Interpretation MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability Most common storm structure in Great Lakes for severe weather MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability Radar Interpretation – October 24th 2001

Favorable area for tornadoes are near the leading edge of “bookend” MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability Schematic

Damaging Winds on Leading Edge. May be miles ahead of rain/thunder Strong/Severe winds, heavy rain, hail and isolated tornadoes MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability Radar Cross Section

Anvil

Rear Inflow Updraft Jet

Downdraft

Shelf Cloud MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Moderate to Strong Shear, Moisture and Instability

Anvil

Anvil Lightning

Spotter Tip: Be aware of lightning well ahead of the main line of thunderstorms! MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) DownburstDownburst MultipleMultiple CellCell StormsStorms -- LinearLinear (Squall(Squall Line)Line) Summary

• Roll or shelf cloud near updraft/downdraft interface and will usually precede severe weather • Heavy rain, wind and hail will follow • Tornadoes may occur on leading edge, especially near the northern “bookend vortex” • Downburst winds possible with the heavy rain •Lightning may occur from the anvil well ahead of the main line of thunderstorms •When you see the line on radar or see the approaching shelf cloud...take immediate action! SevereSevere WeatherWeather JoeJoe SaysSays……

Those squall lines made me a little “squally”. What other kinds of severe thunderstorms are there? SuperCellSuperCell ThunderstormsThunderstorms Strong Shear, Abundant Moisture and Instability

SupercellSupercell ThunderstormsThunderstorms

Responsible for most deadly tornadoes (F3 or higher) ClassicClassic SuperCellSuperCell ThunderstormThunderstorm

Where would you expect a funnel cloud or tornado to form? IndianaIndiana SupercellSupercell withwith TiltedTilted UpdraftUpdraft And Mammatus Wind Speed/Direction Example

40,000 ft Northwest Wind 100 mph

20,000 ft West Wind 80 mph

10,000 ft Southwest Wind 60 mph Mammatus

5,000 ft South Wind 50 mph

Surface Southeast Wind 20 mph ClassicClassic SupercellSupercell A thunderstorm with a persistent and rotating updraft Top View - Schematic Location with respect to storm is important!

H

Shelf Cloud L#4 PositionPosition #4#4 –– InsideInside ““TheThe BearBear’’ss CageCage”” Avoid this location. It is the most dangerous!

L#4

Fort Wayne Indiana, May 26th, 2001 SupercellSupercell ThunderstormsThunderstorms Top View – Radar Perspective – KIWX WSR-88D

April 9th, 2001 – Softball size hail but no Tornadoes! SupercellSupercell ThunderstormsThunderstorms Radar Perspective – Storm Relative Motion (SRM) Radar Location

April 9th, 2001 – Softball size hail but no Tornadoes! SupercellSupercell ThunderstormsThunderstorms Summary

• Roll or shelf cloud still possible on leading edge of rain shield • Heavy rain, wind and hail will follow •Largest hail will be near the updraft • Tornadoes may occur on back side, under the updraft • Wall cloud and funnel cloud will likely precede tornado formation TTornadoornado DamaDamaggee Roanoke, IL. – Parsons Manufacturing Plant – F4

Photos courtesy NWS Central Illinois TornadoTornado DamageDamage Van Wert Cinemas November 10, 2002 – F4 Damage

Photos courtesy Paul Van Dyke TheThe 22 AMAM EvansvilleEvansville AreaArea TornadoTornado November 6, 2005

EastBrook Mobile Home Park •Deadliest Tornado Outbreak in the U.S. Since May 3, 1999 •Deadliest Tornado in Indiana Since April 3-4, 1974 •F3 Rating- Peak Wind 200 mph •Path Length – 41 miles •Average Path Width – 27541 mileyards path length •60 mph Forward Movement •200 Plus Injuries Tornado Seen in Webcam•25 from Fatalities Deaconess Women’s Hospital TornadoTornado DamageDamage Cars Do Not Provide Protection

Department of Natural Resources Vehicle 9/20/02 Monroe City, Knox County, IN Tornado Photo courtesy Department of Natural Resources HailHail Severe hail is ¾” diameter or larger

•• Look for – White hail shaft – Greenish tint to sky LightningLightningLightning NOAANOAA AllAll--HazardsHazards WeatherWeather RadioRadio Protecting You Day and Night!

•• Voice of the National Weather Service, Homeland Security and Emergency Management

•• 24/7 Broadcasts of Routine and Emergency information :

– NWS Warnings/Watches/Forecasts – Terror Alerts and Warnings from DHS – Emergency Messages/Evacuation information from local Emergency Management Agencies

•• For more information, visit the NOAA All-Hazards Weather Radio Web Site at weather.gov NOAANOAA AllAll--HazardsHazards RadioRadio CoverageCoverage AreasAreas

Oshtemo Fort Wayne WWF-34, WXJ-58, 162.475 Mhz 162.550 Mhz Toledo Marion WXL-51, WXM-98, 162.550 Mhz 162.450 Mhz Lima South Bend WXJ-93, WXJ-57, 162.400 Mhz 162.400 Mhz Monticello Angola WXK-74, WXI-94, 162.475 Mhz 162.425 Mhz Laporte North Webster KJY-62, WWG-45, 162.500 Mhz 162.500 Mhz Hebron WNG-689, 162.450 Mhz SpotterSpotter Awareness/ActivationAwareness/Activation What to look and listen for

•• Hazardous Weather Outlook (Days or Hours Ahead) – Issued 5:00 – 6:00 A.M. EST daily, updated as necessary – Today and tonight hazards. Day 2 through day 7 potential hazards – “Spotter information statement” with details of when spotter activation may be needed. •• Watches (Hours Ahead) •• Warnings (Minutes Ahead) •• Utilize NWR, Internet, and local Media sources to stay informed (during an event) •• www.weather.gov/iwx SevereSevere WeatherWeather SpotterSpotter…… If you were preparing for severe weather and saw this image, what storm types and associated weather would you expect at the locations indicated?

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B

A SevereSevere WeatherWeather SpotterSpotter…… A) Supercell Thunderstorm – Tornado, Hail, Wind B) Squall Line – Damaging Winds and Hail C) Supercell Thunderstorm – Hail, Tornado

C

B

A JustJust thethe BeginningBeginning……

•• YourYour locallocal NWSNWS officeoffice conductsconducts freefree severesevere weatherweather observerobserver trainingtraining eacheach yearyear •• 22 hourhour coursecourse •• GivesGives youyou trainingtraining inin spottingspotting severesevere weatherweather outdoorsoutdoors andand safetysafety informationinformation •• YourYour reportsreports toto thethe NWSNWS helpshelps savesave lives!lives! •• weather.govweather.gov forfor moremore informationinformation •• Weather.gov/iwxWeather.gov/iwx –– NorthernNorthern IndianaIndiana OfficeOffice CallCall forfor VideoVideo andand PhotosPhotos

We need your pictures and video to help confirm tornadoes and damage, as well as teach future classes. If you are in a SAFE location and have the chance to shoot video/pictures, please share it with us for inclusion in future presentations.

MyMy ContactContact InformationInformation……

Sam Lashley – Senior Meteorologist NWS IWX [email protected]

Weather.gov/iwx

574-834-1104 x726