View
52
Download
0
Category
Preview:
DESCRIPTION
Lower Colorado Basin. CRFS March 30, 2010. Virgin River. March 1. March 25. 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. A comparison with 2005. - PowerPoint PPT Presentation
Citation preview
Lower Colorado Basin
CRFSMarch 30, 2010
Virgin River
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 1 March 25
Virgin Basin Snow Plot2005 / 2010 / Average
Virgin River Flow (incl. Santa Clara)2005
A comparison with 2005
2005 Flood
2005 snowmelt
Virgin Basin6100 ft
Salt Basin6800 ft
National Operational Hydrologic Remote Sensing Center - NOAA
2010 LOWER COLORADO BASINLAKE MEAD LOCAL (Intervening Flow)
March 120 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
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 ?
Muddy3% Virgin
22%
Paria2%
Little Colorado18%
Havasu5%
Kanab1%
Powell to GC18%
GC to Diamond31%
Annual Inflow Powell to Mead Tributary
Distribution(CBRFC calculated using USGS gages)
Inflow Between Powell & Mead:
Lake Mead Inflow
Forecast Periods: Virgin Basin (Snow + Rain) & Arizona Basins (Rain, some snow)
April – July Runoff
Progressive Forecast Period
Jan-MayJan 15 – MayFeb – May Etc.
Virgin River Basin
Arizona & New Mexico Basins
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 3rd 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 BASINSALT / VERDE
January 20-23, 2010 Precipitation
January flows in the Lower Colorado Basin
Jan Volume 850 % of median
Feb Volume 710 % of median
Salt River - Roosevelt
Weighting ESP for El Nino years resulted in:
Feb 1st Forecast (Feb-May) of +27% over raw ESPMar 1 Forecast (Mar-May) of + 5% over raw ESP
Recommended