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:
September Precipitation :
Water Year 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:
Basin-wide 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
satellite-derived vegetation from the VegDRI product (which updates on Mondays).
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:
Last Month 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 October 28, 2014:
Indian Summer has persisted over the past week across Colorado and the UCRB with high pressure conditions dominating across the region. A couple shortwave disturbances brought some moderate rainfall totals to northwest Colorado and northeast Utah. Outside of this area the precipitation that fell across the drought monitor region was nearly unanimously either 0.01-0.10" or nil.
Temperatures were much above average this week, especially east of the divide where temperatures were at least 9 degrees above the normal. In the UCRB it was still a warm week, but temperature anomalies were a little more modest, and mostly in the 6-9 degree above average range. Following an August and mid-September that were wetter and cooler than normal and transitioning out of the cold season these temperatures aren't especially concerning yet. The level of concern will rise, however, if snowpack totals at high elevations continue to follow current trends for any extended period of time.
Status Quo: The areas of the UCRB that received substantial precipitation over the past week are not currently in drought. Northeast Utah did receive 0.25"-0.50" of precipitation in most areas, and up to 1.00" of precipitation in some select areas, but given the temperature anomalies over the past week this is not enough to justify improvements.
As per NWS Grand Junction's recommendation we will keep a close eye on the Four Corners Region as it sits in a gradient zone between abnormally dry and severe drought conditions. Should the above average temperature and below average precipitation conditions we have seen the last two weeks persist some degradations may be mandated in short order.
Status Quo: Warm, dry conditions across Eastern Colorado over the last two weeks certainly don't justify making any improvements in southeast Colorado at this time. Ground reports indicate that although drought persists in this region summer moisture was sufficient for a promising start to winter wheat season.