Note: This publication is currently undergoing major revisions. The current publication will be replaced with a new publication based on stakeholder requirements and scientific advances. We expect to begin sharing details on this soon. If you have input on content, format, or publication frequency at any time, please contact us at cbrfc.webmasters@noaa.gov.Upper Colorado Water Supply Outlook, June 1, 2010
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through May precipitation
was near 90 percent of average in the Upper Colorado mainstem basin.
May precipitation was also near 90 percent of average.
Snow:
June 1st snow water equivalent was near 55 percent of average in the basin
as a whole. The majority of the remaining snow is above 10,000 feet. The snow
peaked in May at 85% of the average seasonal peak.
--- Upper Colorado basin snow
water equivalent plot
Streamflow:
May streamflow was near 80 percent of average.
Soil Moisture:
Modeled soil
moisture states were near average heading into the winter.
Forecast Summary:
Basin wide precipitation was near average for the month of May. However, some headwater
areas received greater amounts of precipitation. June through July streamflow volume forecasts
range from 43 to 85 percent of average,with a median value of 69%. April through July
streamflow volume forecasts remained the same or increased slightly in certain headwater areas.
The Upper Colorado basin April through July streamflow volume forecasts now range
from 58 to 85 percent of average, with a median value of 72%.
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through May precipitation was 95 percent of average
in the Gunnison Basin. May precipitation was 60 percent of average.
Snow:
June 1st snow water equivalent was 35 percent of average in the Gunnison Basin. There is still some snow
above 11,500 feet with minimal areal extent. The snow peaked above Blue Mesa in early April around 95
percent of the seasonal average.
--- Gunnison basin snow
water equivalent plot
Streamflow:
May streamflow was 70 percent of average.
Soil Moisture:
Modeled soil
moisture states were below average heading into the winter.
Forecast Summary:
May precipitation was much below average in the Gunnison Basin, as were the monthly
streamflow volumes. Also, June 1st snow water equivalent for the Gunnison dropped to 35 percent
below average. June through July volume forecasts range from 56 to 69 percent of
average, with a median value of 62%. This resulted in a 5 percent decrease to the
April through July volume forecasts. The Gunnison Basin April through July forecasts now range
between 66 and 86 percent of average, with a median value of 74%.
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through May precipitation was 100 percent of average
in the entire Dolores Basin. May precipitation was 45 percent of average.
Snow:
June 1st snow water equivalent was 0 percent of average in the Dolores Basin. However, there is still
enough snow above 11,500 feet with minimal areal extent for
some runoff into June. The snow peaked in early April at about 110 percent of the seasonal average.
--- Dolores basin snow
water equivalent plot
Streamflow:
May streamflow was 70 percent of average.
Soil Moisture:
Modeled soil
moisture states were below to much below average heading into the winter.
Forecast Summary:
May precipitation was much below average in the Dolores Basin. In addition, the May 1st snow water
equivalent was below average at 0%, but still some snow was left above 11,500 feet for runoff into June.
June through July volume forecasts range from 30 to 53 percent of average, with a median value of 34%.
This resulted in about a 5% decrease in the April through July forecast volumes.
The Dolores Basin April through July forecasts now range between
67 and 72 percent of average, with a median value of 69%.
Differences between the full period forecasts and the residual forecasts may not exactly equal the actual observed volumes due to rounding conventions (see Definitions section).
Reservoir Monthly Inflow Forecasts
Upper Colorado End of Month Reservoir Contents (kaf)