The images above use daily precipitation statistics from NWS COOP, CoCoRaHS, and CoAgMet stations. From
top to bottom, and left to right: most recent 7-days of accumulated precipitation in inches; current month-to-date
accumulated precipitation in inches; last month's precipitation as a percent of average;
water-year-to-date precipitation as a percent of average.
Last Week Precipitation:
Water Year 2015 Precipitation:
SNOTEL AND SNOWPACK
The top left image shows the Natural Resources Conservation Service's SNOTEL water-year-to-date
precipitation percentile rankings. The top right image shows sub-basin averaged snow water
equivalent accumulations as a percent of average. The images below show accumulated snow water
equivalent in inches (green) compared to average (blue) and last year (red) for several different sub-basins
across the UCRB (and were created by the Colorado Basin River Forecast Center).
SNOTEL Precipitation Percentiles:
Westwide Snow Water Equivalent (SWE) Percent of Normal:
SWE Timeseries Graphs:
STANDARDIZED PRECIPITATION INDEX
Standardized Precipitation Index standardizes precipitation accumulations for a specified time period
into percentile rankings. -1.0 to -1.5 is
equivalent to a D1 to D2. -1.5 to -2.0 is equivalent to a D2 to D3. -2.0 and worse is equivalent to a D3 to
D4. 30- and 60-day SPIs focus on short-term conditions while 6- and 9-month SPIs focus on long-term
conditions. SPI data provided by High Plains Regional Climate Center.
Short Term (30-day):
Long Term (6-month):
The top left image shows 7-day averaged streamflows as a percentile ranking across the UCRB. The top
right image shows 7-day averaged discharge over time at three key sites around the UCRB: The Colorado
River at the CO-UT state line; the Green River at Green River, UT; and the San Juan River near Bluff,
UT. All streamflow data provided by United States Geological Survey.
The top left image shows VIC modeled soil moisture as a percentile ranking. The top right image shows
VIC plus SWE total soil moisture storage.
The above image shows last month's and this month's current volumes of the major reservoirs in
the UCRB, with percent of average and percent of capacity.
All images show temperature departures from average over different time periods (last 7 days on top
left; month-to-date on top right; last full month on bottom). Temperature departure
maps provided by HPRCC ACIS.
Last Week Temperatures:
FORECAST AND OUTLOOK
The top two images show Climate Prediction Center's Precipitation and Temperature outlooks for 8 - 14 days. The middle image shows the 3 months Precipitation outlook. The bottom left image shows the Hydrologic Prediction Center's Quantitative
Precipitation Forecast accumulation for the five days between Tuesday 12Z and ending Sunday 12Z. The
bottom right image shows the Climate Prediction Center's most recent release of the U.S. Seasonal
Above is the most recent release of the U.S. Drought Monitor map for the UCRB region. Below shows
the proposed changes for this week, with supporting text.
Summary for March 3, 2015:
A much needed surge of moisture benefited many of the UCRB subbasins this week, especially in the San Juan river basin where snowpack had been lagging much behind normal (and continues to, even with the recent moisture). This moisture was accompanied by below normal temperatures across the UCRB. East of the divide also saw smaller amounts of moisture over the SE plains, but likely not enough to warrant any improvements at this time.
UCRB: Status quo is recommended considering D1 was just added and snowpack and water year precipitation are still lagging across most of the basins. If moisture continues to improve snowpack over the next week, trimming of the D1 will be considered. That would be more likely for the Yampa/White/Colorado than the Gunnison or San Juans considering where snowpack is currently.
The plains saw above normal moisture for February, however normals are rather low in that area for February (0.3-0.5"). If moisture continues to benefit SE Colorado as their wetter seasons ramp up, improvements will be made. Considering the lingering impacts and length of time in drought, status quo is recommended for this week.
NE Colorado has dried out slightly but not enough to warrant degradation after good moisture last summer. If impacts start being realized, degradations will be made at that time.