HYDROLOGIC OUTLOOK NATIONAL WEATHER SERVICE DENVER CO 1256 PM MST FRI MARCH 10 2006
...SPRING FLOOD AND WATER RESOURCES OUTLOOK...
THIS OUTLOOK IS FOR THE UPPER COLORADO AND NORTH PLATTE BASINS IN NORTH CENTRAL COLORADO AND THE SOUTH PLATTE BASIN OF NORTHEAST COLORADO.
...THE POTENTIAL FOR SPRING SNOWMELT FLOODING IN THE UPPER COLORADO BASIN IS NEAR TO ABOVE AVERAGE... ...THE POTENTIAL FOR SPRING SNOWMELT FLOODING ALONG THE NORTH PLATTE AND SOUTH PLATTE BASINS IN COLORADO IS BELOW AVERAGE...
THE VALUES IN THE TABLE BELOW ARE VALID MARCH 14 2006 TO SEPTEMBER 30 2006. THE 90 THROUGH 10 PERCENT COLUMNS INDICATE THE CHANCE THAT A LOCATION ON A RIVER COULD RISE ABOVE THE LISTED STAGE LEVELS IN THE NEXT 6 MONTHS. FOR EXAMPLE: THE CACHE LA POUDRE RIVER AT FORT COLLINS HAS A FLOOD STAGE OF 11 FEET. THERE IS A 20 PERCENT CHANCE THAT THE RIVER WILL RISE ABOVE 7.7 FEET IN THE NEXT 6 MONTHS.
LOCATION FS(FT) 90% 80% 70% 60% 50% 40% 30% 20% 10% ----------- ---- --- --- --- --- --- --- --- --- --- CACHE LA POUDRE RIVER FORT COLLINS 11 4.9 5.8 6.1 6.2 6.4 7.1 7.3 7.7 9.4 GREELEY 9 3.7 5.5 6.0 6.2 6.6 7.5 7.6 7.7 8.8
THE FOLLOWING ARE PRELIMINARY STREAMFLOW VOLUME FORECASTS FOR SELECTED POINTS:
MOST PROBABLE FORECAST
VOLUME PERCENT STREAM AND STATION PERIOD 1000 AF OF AVG _________________ ______ _______ _______ SOUTH PLATTE RIVER ANTERO RESERVOIR INFLOW APR-SEP 25 121 SPINNEY MTN RES INFLOW APR-SEP 77 112 11-MILE CANYON RES INFLOW APR-SEP 81 113 CHEESMAN LAKE INFLOW APR-SEP 166 117 SOUTH PLATTE APR-SEP 285 112
BEAR CREEK EVERGREEN ABV APR-SEP 30 120 MORRISON APR-SEP 36 116
CLEAR CREEK GOLDEN APR-SEP 150 112
ST VRAIN CREEK LYONS APR-SEP 112 105
BOULDER CREEK ORODELL NR APR-SEP 61 115 ELDORADO SPRINGS NR APR-SEP 47 102
BIG THOMPSON RIVER CANYON MOUTH APR-SEP 115 98
CACHE LA POUDRE CANYON MOUTH APR-SEP 275 100
NORTH PLATTE RIVER NORTHGATE NEAR APR-SEP 310 115
COLORADO RIVER LAKE GRANBY APR-JUL 230 102
WILLOW CREEK WILLOW CREEK RES APR-JUL 53 104
FRASER RIVER WINTER PARK APR-JUL 22 110
WILLIAMS FORK RIVER WILLIAMS FORK RES APR-JUL 110 116
MUDDY CREEK WOLFORD MTN RES APR-JUL 75 125
BLUE RIVER DILLON RES APR-JUL 220 132 GREEN MTN RES APR-JUL 360 129
COLORADO RIVER KREMMLING APR-JUL 1050 121
THE POTENTIAL FOR SPRING FLOODING DUE TO SNOWMELT IS HIGHER THAN USUAL IN THE BLUE RIVER BASIN AND ALONG THE UPPER COLORADO RIVER FROM HOT SPRINGS TO EAST OF KREMMLING...AND NEAR AVERAGE. ELSEWHERE IN THE UPPER COLORADO BASIN. ALTHOUGH THE SNOWPACK IN THE HIGHER ELEVATIONS EAST OF THE CONTINENTAL DIVIDE IS NEAR TO SLIGHTLY ABOVE AVERAGE...THERE IS LITTLE POTENTIAL FOR FLOODING IN THE SOUTH PLATTE AND NORTH PLATTE BASINS DUE TO SNOWMELT.
OUTLOOKS ARE ROUTINELY ISSUED IN FEBRUARY AND MARCH TO GIVE ADVANCED NOTICE OF POSSIBLE FLOODING. THEY ARE BASED ON SOIL MOISTURE...SNOWPACK MAGNITUDE AND STREAMFLOW AT THE TIME THE OUTLOOK IS ISSUED. OUTLOOKS ARE ALSO BASED ON NORMAL FUTURE TEMPERATURE AND PRECIPITATION.
TEMPERATURES THIS WINTER HAVE RANGED FROM SLIGHTLY ABOVE NORMAL IN NORTH CENTRAL COLORADO TO MUCH ABOVE NORMAL IN THE NORTHEAST. PRECIPITATION RANGED FROM ABOVE NORMAL WEST OF THE CONTINENTAL DIVIDE TO BELOW NORMAL ON THE EASTERN PLAINS.
SNOWPACK IN THE UPPER COLORADO BASIN IS 109% OF AVERAGE. THE UPPER COLORADO BASIN SAW PERIODS OF SIGNIFICANT SNOWFALL THROUGH JANUARY FOLLOWED BY DRIER CONDITIONS IN FEBRUARY AND EARLY MARCH. THE SNOWPACK IN THE HIGHER ELEVATIONS OF THE SOUTH PLATTE BASIN IS 102% OF AVERAGE. THERE WAS ABOVE AVERAGE PRECIPITATION IN OCTOBER...NOVEMBER AND DECEMBER BUT A CONTINUING DECREASE IN PRECIPITATION IN JANUARY AND FEBRUARY WHICH TOOK ITS TOLL ON THE SNOWPACK IN THE SOUTH PLATTE BASIN.
STREAMFLOW AND SOIL MOISTURE CONDITIONS ARE GENERALLY NEAR TO BELOW AVERAGE. THERE IS AMPLE RESERVOIR STORAGE AVAILABLE FOR SPRING SNOWMELT RUNOFF. COMBINED RESERVOIR STORAGE WAS 68% OF CAPACITY IN THE UPPER COLORADO BASIN AND 70% OF CAPACITY IN THE SOUTH PLATTE BASIN ON MARCH 1ST.
THE CPC 8-14 DAY OUTLOOK INDICATES EQUAL CHANCES OF ABOVE OR BELOW NORMAL TEMPERATURES AND A SLIGHTLY ELEVATED CHANCE OF ABOVE NORMAL PRECIPITATION. THE OUTLOOK FOR APRIL...MAY AND JUNE CALLS FOR NEAR TO SLIGHTLY ABOVE NORMAL TEMPERATURES AND NEAR TO SLIGHTLY BELOW NORMAL PRECIPITATION.
THE PROBABILISTIC NUMBERS CONTAINED IN THIS OUTLOOK ARE CALCULATED USING MULTIPLE SEASON SCENARIOS FROM 30 OR MORE YEARS OF CLIMATOLOGICAL DATA INCLUDING CURRENT CONDITIONS OF THE RIVER...SOIL MOISTURE...AND LONG-RANGE OUTLOOKS OF TEMPERATURE AND PRECIPITATION. BY PROVIDING THE COMPLETE RANGE OF PROBABILITIES...THE LEVEL OF RISK ASSOCIATED WITH LONG-RANGE PLANNING DECISIONS CAN BE DETERMINED. THESE PROBABILISTIC FORECASTS ARE PART OF THE NATIONAL WEATHER SERVICE'S ADVANCED HYDROLOGIC PREDICTION SERVICE.
THIS IS THE ONLY SCHEDULED SPRING FLOOD AND WATER RESOURCES OUTLOOK FOR 2006. UPDATED OUTLOOKS WILL BE ISSUED AS CONDITIONS WARRANT.
VISIT OUR HOME PAGE AT WWW.CRH.NOAA.GOV/BOU/ FOR ADDITIONAL WEATHER...CLIMATE AND HYDROLOGIC INFORMATION.
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