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, March 1, 2011
Upper Colorado Water Supply Outlook, March 1, 2011
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through February precipitation
was near 135 percent of average in the Upper Colorado mainstem basin.
February precipitation was near 120 percent of
average in the basin as a whole.
Snow:
March 1st snow water equivalent was near 130 percent of average in the basin
as a whole; this is near 100% of the average seasonal peak.
--- Upper Colorado basin snow
water equivalent plot
Streamflow:
February streamflow was near 95 percent of average.
Soil Moisture:
Modeled soil
moisture states were near to above average heading into the winter.
Climate Forecasts:
Climate forecasts were not a factor because there is not a strong correlation
between La Nina conditions and winter precipitation in the Upper Colorado mainstem basin.
Forecast Summary:
As of March 1st the percent of average
of both the seasonal precipitation and snow water equivalent were much above average in the
basin as a whole. Almost all forecast volumes were raised from last month due to yet another
month of above average precipitation. Current April through July streamflow volume
forecasts range between 115 and 139 percent of average with a median
value of 125 percent.
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through February precipitation was 120 percent of average
in the Gunnison basin. February precipitation was 105 percent of average.
Snow:
March 1st snow water equivalent was near 120 percent of average in the Gunnison basin; this is 95% of the seasonal peak.
--- Gunnison basin snow
water equivalent plot
Streamflow:
February streamflow was 85 percent of average.
Soil Moisture:
Modeled soil
moisture states were below to near average heading into the winter.
Climate Forecasts:
Climate forecasts were not a factor because there is not a strong correlation
between La Nina conditions and winter precipitation in the Gunnison basin.
Forecast Summary:
February precipitation throughout the Gunnison basin was average at 105%. Seasonal precipitation for the Gunnison basin dropped a little from last month to 120% of average.
March 1st seasonal snow water equivalent for the Gunnison was above average with 120%; whereas the snow water equivalent is 95% of the average seasonal peak.
The percent of average for both seasonal snow water equivalent and seasonal precipitation decreased little from last month over the entire basin. Since there were slight
increases in both the seasonal snow water equivalent and seasonal precipitation in the northern portions of the Gunnison basin, the current April through July streamflow
volume forecasts remained the same from last month's forecast. Current April through July streamflow volume forecasts range between 99 and 126 percent of average with a median value of
110 percent.
The following conditions influenced this month's forecasts:
Precipitation:
Seasonal October through February precipitation was 105 percent of average
in the entire Dolores basin. February precipitation was just 65 percent of average.
Snow:
March 1st snow water equivalent was 95 percent of average in the Dolores basin as a whole; this is 75% of the seasonal peak.
--- Dolores basin snow
water equivalent plot
Streamflow:
February streamflow was 75 percent of average.
Soil Moisture:
Modeled soil
moisture states were average to slightly below average heading into the winter.
Climate Forecasts:
The correlation of La Nina and April through July water volumes in the Dolores basin is small that
it did not influence the forecast process.
Forecast Summary:
February precipitation throughout the Dolores basin was much below average at 65%. Seasonal precipitation for the Dolores basin dropped from last month to 105% of average.
March 1st seasonal snow water equivalent for the Dolores was average with 95%; whereas the snow water equivalent is 75% of the average seasonal peak.
Since the percent of average for both seasonal snow water equivalent and seasonal precipitation decreased from last month, the current April through July streamflow volume forecasts
dropped in the Dolores Basin from last month's forecast. Current April through July streamflow volume forecasts range between
83 and 88 percent of average, with a median value of 85 percent.
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)