1. CRFS March 30, 2010

2. Virgin River

3. NWS-SWS: 90 NWS-ESP: 60 55 (+8-15% El Nino weighted) NRCS daily: 80 NRCS statistical: 78 Coordinated: 80 / 195% median or 125% average March 1March 25

4. Virgin Basin Snow Plot 2005 / 2010 / Average Virgin River Flow (incl. Santa Clara) 2005 A comparison with 2005 2005 Flood 2005 snowmelt

5. Virgin Basin 6100 ft Salt Basin 6800 ft National Operational Hydrologic Remote Sensing Center - NOAA

6. 2010 LOWER COLORADO BASIN LAKE MEAD LOCAL (Intervening Flow) March120 KAF (100% of average) April 120 KAF (104% of average) May 80 KAF ( 96% of average) April - July Forecast: 270 KAF ( 93% of average) March - July Forecast: 390 KAF ( 95% of average) ESP Generated

7. Colorado River - Lake Powell to Diamond Fork Little Colorado Paria River Virgin River Muddy Creek Intervening Flow Forecasts: Lake Powell to Lake Mead / Where is the skill ?

8. Annual Inflow Powell to Mead Tributary Distribution (CBRFC calculated using USGS gages) Inflow Between Powell & Mead: Lake Mead Inflow

9. Forecast Periods: Virgin Basin (Snow + Rain) & Arizona Basins (Rain, some snow) April – July Runoff Progressive Forecast Period Jan-May Jan 15 – May Feb – May Etc. Virgin River Basin Arizona & New Mexico Basins

10. Winter 2010 Highlights  Winter storm pattern that resulted was in line with the El Nino climate conditions  Significant rainfall in the Lower Colorado during the 3 rd week of January (~10” in 24 hrs)  Very large snowpack in Arizona, significant snow at lower elevations  Much above median volumes observed in January, much above median seasonal volumes expected.  Forecast Challenge: Possibility of additional large precipitation events (El Nino)  Forecast Challenge: The non-typical large snowpack and resulting volumes.  Forecast Challenge: Dry soils exist under high elevation snowpack. 2010 LOWER COLORADO BASIN SALT / VERDE

11. January 20-23, 2010 Precipitation January flows in the Lower Colorado Basin Jan Volume 850 % of median Feb Volume 710 % of median

12. Salt River - Roosevelt Weighting ESP for El Nino years resulted in: Feb 1 st Forecast (Feb-May) of +27% over raw ESP Mar 1 Forecast (Mar-May) of + 5% over raw ESP