1. May 3.2007 West Gulf River Forecast Center Rio Grande Hydrologic Services Expansion Meeting

2. Presentation Outline Introduction to WGRFC River Forecast Process Rio Grande Forecast System Challenges and Complications

3. The Function of WGRFC To provide the most accurate and timely river stage forecasts… through a combination of our knowledge/skill of both meteorology and hydrology This is accomplished through 2 main functions: –HAS (Hydrometeorological Analysis and Support) Operations 3 Forecasters –Hydrologic Operations 9 Forecasters

4. WGRFC Staff

5. WGRFC Hours of Operation Normal Hours –6:00 a.m. – 10:00 p.m. Extension of hours –Event driven and/or in coordination with WFOs –“Close the Gap” Overnight Shifts –10:00 p.m. – 6:00 a.m. –Scheduled when prolonged rainfall/flooding event is expected

6. The WGRFC Area WGRFC is one of 13 River Forecast Centers that provide precipitation and river forecasts for the Continental U.S. and Alaska. WGRFC’s area of responsibility extends into Mexico in order to cover tributary rivers that flow into the Rio Grande.

7. Weather Forecast Offices (WFOs) Serving the Rio Grande Drainage River Forecast Center issues stage forecasts to area Weather Forecast Office. Weather Forecast Office adds location specific impact statements and disseminates to the public.

8. Forecast Process

9. Big Bend Region - 07/28/04 Gauge Only FieldRaw Radar Field Satellite Derived Precipitation Best Estimate QPE (Multi-sensor Field)

10. Precipitation Estimates

11. Averaged Precipitation

14. AHPS Web Page

15. WGRFC Forecast Types Daily Forecasts – Issued every morning regardless of flow El Paso Lare do Flood Only Forecasts - Begin issuance when location is forecast to rise above a “criteria” level. Forecasts are updated until level drops below criteria. This includes the majority of WGRFC forecast points Recreation Forecasts – Issued weekly on Wednesday afternoon for upcoming weekend flows. Presidio Boquillas (Rio Grande Village)

16. River Recreation Forecast

17. Rio Grande Forecast System

18. Rio Grande Drainage Non-contributing Area

19. Upper Watershed (above Elephant Butte ) Upper Rio Grande Drainage  Water Supply Forecast  Runoff contained in lake

20. Pecos Basin Pecos River Drainage

21. Rio Conchos Basin (above Luis Leon) Rio Conchos Drainage

22. Rio Grande at El Paso Rio Grande nr Candelaria EPRT2 CDET2  3 Day travel Time from EPRT2-CDET2  Rarely Happens  Satellite Telemetered Observations

23. Rio Grande above Rio Conchos Presidio PIOT2  18 Hr travel Time from CDET2-PIOT2  Satellite Telemetered Observations

24. Luis Leon Reservoir La Boquilla  2.3 M Acre Feet Storage Luis Leon  273,000 Acre Feet Storage  20,600 sq mi Drainage Area  1 Day Travel Time to Presidio

25. Rio Grande below Rio Conchos Presidio (International Bridge) Rio Conchos belowLuis Leon  3414 sq mi  12 hr Crest  Satellite Telemetered Data from Mexican Gage PRST2 Cibilo Creek  269 sq mi  6 hr Crest  Satellite Telemetered Data

26. Rio Grande nr Presidio (Weir) PRDT2 Alamito Creek  860 sq mi  6 hr Crest  Satellite Telemetered Data

27. Rio Grande nr Lajitas  6-12 Hr travel Time from PRDT2  Daily Observations TGAT2

28. Terlingua Creek nr Terlingua TNGT2 Terlingua Creek  784 sq mi  12 hr Crest  Satellite Telemetered Data

29. Rio Grande nr Castolon CSTT2  Observed Data on Request  Forecasts based on TELT2 hydrologic parameters (high uncertainty)

30. Rio Grande at Johnson Ranch TELT2  6-12 Hour Travel Time from TGAT2  Satellite Telemetered Data

31. Rio Grande nr Boquillas Ranger Station (Rio Grande Village) BOQT2  6-12 Hr travel Time from CSTT2  Daily Observed Data

32. Rio Grande nr Heath Canyon HECT2  6-12 Hr travel Time from BOQT2  No Observed Data

33. Rio Grande nr Dryden DYNT2  6-12 Hr travel Time from HECT2  Satellite Telemetered Data

34. Rio Grande at Foster Ranch LNYT2  6-12 Hr travel Time from DYNT2  Satellite Telemetered Data

35. Challenges & Complications

36. CHALLENGES & COMPLICATIONS Hydrologic Forecasting along the Big Bend of the Rio Grande No Radar Coverage Few Rain Gages Limited Streamflow Observations Mountainous, Rugged Landscape: –Fast Stream Response –Difficulty in Getting Around International Boundary: –Data and Forecast Exchange –Communication Complexities

37. Radar Coverage Map

38. http://www.srh.noaa.go v/wgrfc Limited Radar & Precip. Gages Gauge Only FieldRaw Radar Field Satellite Derived Precipitation Best Estimate QPE (Multi-sensor Field)

41. Availability of International Data

42. Please visit our website at: www.srh.weather.gov/wgrfc For Additional Questions or Comments, Please contact us: 817-831-3289 Frank.Bell@noaa.gov Robert.Corby@noaa.gov www.srh.weather.gov/wgrfc Frank.Bell@noaa.gov Robert.Corby@noaa.gov Thank You for Your Time!

43. Rio Grande Drainage

44. Big Bend Area Forecast Points And River Forecast Source Red dots denote Forecast Points

45. WGRFC Web Page Customers can zoom to specific regions of the WGRFC forecast area from the main status map Icons in Status Map indicate current state of rivers based on color coding located below map “Flood Summary” located just below status map