X-Banding the Bay Area’s Real Time Rainfall Monitoring and Storm Forecasting Capabilities Project to Add 5 Radars to Bay Area & Make Use of Data 2 | Talk Outline Weather Radars- Background AQPI Project What & Where, Why, Who, When? How will rainfall data be used? X-Band Radar: Quick Start Guide Conclusions and Acknowledgements 3 | Weather Radar Basics Radar rotates up to 360 degrees, and 20 degrees in the vertical As it rotates, sends out SHORT pulses (0.00000157 seconds) with LONGER listening Periods (0.00099843 seconds) Process repeated 1300 times per second Doppler Effect is used to calculate the distance and direction of radio waves reflected by rain drops, snow flakes, hail, etc. 4 | Main Types of Radar SUBTITLE Wavelength Frequency Advantages/ Type Use Example (cm) (GHz) Drawbacks Very Long Range Turbulence L-Band 15 – 30 1 - 2 Easy to Install Studies but Lower Resolution National Long Range but S-Band 8 – 15 2 - 4 Weather Large Dish, Antenna Service and Motor required TV Stations Shorter Range but C-Band 4 – 8 4 - 8 AQPI Project Smaller Dish, Less Power Required Very Short Range but AQPI Project Detects Smaller X-Band 2.5 – 4 8 - 12 Police Speed Particles & Easy to Radars Install 0.75 – 1.2 27 – 40 Cloud Detection Very Short Range but K-Band 1.7 – 2.5 12 - 18 Police Radars Very High Resolution 5 | Weather Radar – Dual Polarization Dual Polarized Radar (Added to NEXRAD 2012- 2015) Allows for: Improved detection of weather type (hail vs. snow vs. rain). Distinction: Weather elements vs. other (Insects, Smoke, Birds) Detection ability improves as radar wavelength decreases, Frequency6 | increases. Weather Radars in Bay Area Two S-Band Radars – NWS, NEXRAD (KDAX &KMUX). Advanced, Use Dual Polarization Two C-Band Radars – KGO & KPIX (TV Stations). Older, Less Reliable, Single Polarization. Also: NOAA operates 3 radar wind profilers along CA coast. 7 | Bay Area Radar Shortcomings Mountainous topography and high elevations of radars weaken atmospheric river detection NEXRAD NEXRAD Radar sees too high Radar sees where you need it most Radar blocked 8 | Bay Area Radar Shortcomings Existing S-Band Radars have coarser resolution (1 km, updating every 5-6 minutes) At their large wavelengths/frequency, differential phase generally too large for rainfall estimation 9 | Talk Outline Weather Radars- Background AQPI Project What & Where, Why, Who, When? How will rainfall data be used? X-Band Radar: Quick Start Guide Conclusions and Acknowledgements 10 | AQPI Project – Where (Bay Area) & What S-band NEXRAD 1 C-Band 100 km Range Tracks storms coming from Pacific Ocean X-band Mt. S-band 4 X-Bands C-band Sonoma NEXRAD Bay Hill 40 km Range High Spatial (100 m) and X-band RKRDG X-band Temporal Montara Peak Resolution (1-2 X-band XSCV min) S-band NEXRAD 11 | AQPI Project – Why? Better Resolution – Temporally and Spatially Every 1-2 minutes vs. 6 minutes X-BAND RADAR S-BAND RADAR 12 | AQPI Project – Why? Capturing Spatial Variability X-Band Radars capture spatial variability of rainfall; point measurements only measure local rainfall Radar Rain Gauge Disdrometer “The total area measured globally by all currently available rain gauges is surprisingly small, equivalent to less than half a football field or soccer pitch.” from Kidd et al. (2017) 13 | AQPI Project – Why? Improved Accuracy 14 | AQPI Project – Why? Improved Tracking of Lower Elevation Atmospheric Rivers E.g. 2017 Coyote Flooding NEXRAD NEXRAD Radar sees too high Radar sees where you need it most Radar blocked 15 | AQPI Project – Why? Allows for “NowCast” Rainfall Predictions– 30 – 60 minutes out (to fill in gaps between HRRR modeling) Makes use state-of-the art X-Band Radars constructed at Colorado State University (V. Chandrasekar, Haonan Chen, Francesc Junyent) Uses aspect of dual polarization (Differential Phase)- allows for more accurate rainfall estimation – compared with NEXRAD 16 | AQPI Project – Who? Funding – Department of Water Resources Lead Agency – Managing Project – Sonoma County Agencies Hosting Radars– Sonoma County (Jake Spaulding), SCVWD, SFPUC, Two others (or possibly more) Deputy Project Director & Engineering Lead– V. Chandrasekar & CIRA, Colorado State University End Use Agencies – NOAA, USGS, SCVWD, Scripps Strategic Planning– Morrison and Associates Others 17 | AQPI Project – When? Temporary Radars Installed Currently SCVWD – Installed for Super Bowl 50 (Spring 2016) & Sept. 23, 2017 - Present Sonoma County – Installed Spring 2018 Permanent Radar Installation- Aiming for two by end of 2018; others to follow Funding for Project extends until End of 2021 18 | Talk Outline Weather Radars- Background AQPI Project What & Where, Why, Who, When? How will rainfall data be used? X-Band Radar: Quick Start Guide Conclusions and Acknowledgements 19 | How will Rainfall Data be Used? To fill in spatial and temporal gaps of existing NEXRAD gauge network To fill in gaps in existing SCVWD rain gage network To calibrate SCVWD’s Rain Gauge Network and vice-versa Initial conditions for NOAA’s HRRR model for 24 hour weather forecasts, updated every hour For Creating “NowCasts” – 30-60 minute forecasts to fill in gaps between HRRR predictions Input for USGS Hydro CoSMoS – for 48 hour forecasts of streamflow and storm surge Input for SCVWD own flood forecast models 20 | Talk Outline Weather Radars- Background AQPI Project What & Where, Why, Who, When? How will rainfall data be used? X-Band Radar: Quick Start Guide Conclusions and Acknowledgements 21 | X-Band Radar: Quick Start Guide Find Radar Site Good Coverage? Right Elevation? Clear line of sight? Location (Tower or Building) for mounting Radar? Security? Internet Access (X-Band is a bandwith hog) and Power (single phase, 220 V, 20 Amps)? Location for server? Easy Access for installation/maintenance? E.g., crane accessibility? Safety Concerns? Etc. How’s the roof access? 22 | X-Band Radar: Quick Start Guide Design & Build Mounting Structure Check that proposed site can support X-Band Radar (2500 lbs) Design Platform for X-Band Radar Ensure that proposed mounting structure is designed for site conditions (winds, etc) Hire contractor to build the structure. 23 | X-Band Radar: Quick Start Guide Get Permissions From site owner (our water treatment plant staff) Environmental Clearance (CEQA) FCC – X-Band shares wavelengths with police speed radar, so this is required and must be obtained every 5 years Building permit (for mounting structure) 24 | X-Band Radar: Quick Start Guide Confirm Adequate Internet & Power May need to install conduit to route cables to roof Ensure internet and power (220 V) are adequate At District, we had to install a dedicated DSL line for internet What about security of internet? 25 | X-Band Radar: Quick Start Guide Coordinate Installation Order Crane Coordinate with X-Band Radar Delivery Schedule Check that Installation crew (CSU staff) will have access to site on installation day Have liaison staff on site. 26 | X-Band Radar: Quick Start Guide Trouble-shoot Internet cable mysteriously breaks Conduit (for running cables) is barely wide enough to pull cables Brand new firewall failed Large custom storage boxes needed storage location 27 | Acknowledgements Colorado State University V. Chandrasekar, Ph.D. NOAA Rob Cifelli, Ph.D. Haonan Chen, Ph.D. Sonoma County Jake Spaulding 28 | Questions? 29 | One last item.. Install The Disdrometer 30 | In Situ and Remote Measurement of Rainfall Rain Gauge ● Disdrometer ● Weather Radar Radar Rain Gauge Disdrometer “The total area measured globally by all currently available rain gauges is surprisingly small, equivalent to less than half a football field or soccer pitch.” from Kidd et al. (2017) Hydro-CoSMoS An Integrated Flood Forecast Model for San Bay River Francisco Bay based on 10 years of research and development in partnership with leading oceanographic research institutions Applications throughout California with public and private sector end‐users In Situ and Remote Measurement of Rainfall Rain Gauge ● Disdrometer ● Weather Radar Several types of rain gauges (e.g., weighing gauges, tipping-bucket gauges) • systematic error • sampling interval and the bucket volume • arduous deployment and maintenance Commonly used disdrometers: Parsivel and 2-D video Radar disdrometer (2DVD) Point measurements, Rain Gauge Disdrometer hard to capture the complex distribution of precipitation “The total area measured globally by all currently available rain gauges is surprisingly small, equivalent to less than half a football field or soccer pitch.” from Kidd et al. (2017) X-Band Radar: Quick Start Guide Trouble-shooting Examples Disdrometer? 34 | AQPI Project – Why? 35 | AQPI Project – Why? X-Band Radars capture spatial variability of rainfall; point measurements only measure local rainfall Radar Rain Gauge Disdrometer “The total area measured globally by all currently available rain gauges is surprisingly small, equivalent to less than half a football field or soccer pitch.” from Kidd et al. (2017) 36 | NOAA Next-Generation model development HRRR Ensemble Probability of 6‐hr rainfall (24‐hour forecast) Provides Forecast Uncertainty Information HRRRe >2” >1” Under development now Anticipate implementation as early as 2020 Probability of 6‐hr rainfall >= x inches within 40 km (%) Weather Radars in Bay Area - Shortcomings 38 | District’s Forecasting System Currently relies on NOAA forecasts (how frequent?) Future: will use HRRR forecasts 39 | AQPI Project – Why? ?? KMUX NEXRAD – elv. 1077.4 m AMSL KMUX Radar ShootingKMUX Bright Band Snow Bright band Rain 40 | 1km Bullet Points Example SUBTITLE Integer varius justo sed diam vehicula dignissim. Vivamus mollis volutpat arcu, non porta nibh lacinia vitae. Sed volutpat massa vel ipsum consequat non euismod quam sodales. Hyperlink example—valleywater.org 41| Footer Bullet Points Example SUBTITLE First level Second level Third level Fourth level Fifth level 42| Footer Example—Board Compensation SUBTITLE In accordance with California Water Code and District Ordinance No. 08-02, the Board’s per diem compensation is $260.03 per day for each day’s attendance at Board meetings, or for each day’s service rendered as a District Board member up to 10 days per month.