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.
Additional Precipitation Links: (will take you to an outside website)
High Plains Regional Climate Center's ACIS Maps
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 Weather Prediction Center's Quantitative
Precipitation Forecast accumulation for the seven days between Tuesday 12Z and ending Tuesday 12Z. The
bottom right image shows the Climate Prediction Center's most recent release of the U.S. Seasonal
Short Term: (6/28)
- The North American Monsoon is scheduled to make a very welcome return this week. All of Colorado excpet the extreme northeast corner are forecast over half an inch of precipitation for the coming week. The wettest areas will be the central Rockies, the San Juans, Sangre de Cristos, and foothills to the immediate east. Temperatures will also cool by 5-10 degrees. The northern and western portions of the UCRB will also benefit from this moisture, but not to the same degree. Here weekly precipitation totals are likely to fall in the 0.25-0.50" range with higher amounts anticipated at higher elevations.
- The 8-14 day precipitation outlook shows increased chances for above average precipitation for southeast Utah and southern Colorado. The northermost reaches of the Upper Green River Basin will see increased chances of below average precipitation.
- The 8-14 day temperature outlook shows increased chances for above average temperatures for the entirety of the UCRB. Most of eastern Colorado and the San Luis Valley are forecast equal chances of above and below average temperatures. The northern Front Range and northeast plains will see slightly elevated chances for above average temperature.
- The Climate Prediction Center July through September outlook shows equal chances of above an below average precipitation for the entirety of the UCRB and eastern Colorado.
- The seasonal drought outlook for Colorado and the UCRB shows no likely drought development over the next three months, and removal likely in the southeast corner of the state.
Above is the most recent release of the U.S. Drought Monitor map for the UCRB region.
the proposed changes for this week, with supporting text.
Summary: June 28, 2016
The past week was a scorcher for the Upper Colorado River Basin and eastern Colorado. The UCRB saw average temperatures for the week of over 85 degrees in some areas. As is often the case this time of year the proper strategy to cool off would be to retreat to high elevations. Mountain areas saw average temperatures in the 60s this week. These temperatures were above normal everywhere for the week across the UCRB and eastern Colorado. In most locations weekly temperature anomalies were between +4 and +8 degrees Fahrenheit.
With the exception of some high elevation convective showers, the UCRB was very dry over the past week, receiving less than 0.10" of precipitation in most locations. East of the divide, thunderstorms generating off the mountains and traveling southeast dropped over 0.50" of precipitation across much of the Arkansas River Basin. Isolated areas received over an inch. The amount of area in northeast Colorado that received above normal rainfall over the past week was lower. Most of northeast Colorado received less than 0.25".
This is the driest time of year for much of the UCRB, but this June has been even drier than normal. Most 30-day SPIs in the UCRB are between -1 and 0. 30-day SPIs are between -2 and -1 in Duchesne and Uintah Counties in Utah, Grand and Route Counties in Colorado, and Lincoln County in Wyoming. The eastern side of Colorado is closer to normal on short timescales, but also showing more variability. On longer timescales most areas are in pretty good shape. The western fringe of the UCRB near the Wasatch Range is showing moderate short and long-term dryness, and this is currently reflected by D0.
The UCRB is doing well in terms of water storage with the obvious exception of Lake Powell. Cumulative streamflow at major indicator sites along the Green, Colorado, and San Juan Rivers is at or near normal for 2016 to date. Only 4% of gages in the UCRB are reporting 7-day streamflows below normal. Lake Dillon, McPhee, Green Mountain, and Lake Granby are all near their capacities. Blue Mesa, Flaming Gorge, and Navajo Reservoirs are all above average. Lake Powell has been boosted to 77% of its average late June level, which is up from around 70% a month ago.
Impacts of short-term hot and dry conditions on root zone soils and vegetative health have been largely muted by better long-term conditions, and by relaxed evaporative demand in April and May to start the growing season. Using a combination of the Evaporative Demand Drought Index and CoAgMet indicator sites, ET was found to be below or near normal across the UCRB and eastern Colorado to start the growing season. Shallow soils and vegetation with near-surface roots are drying out in many areas, but the only area showing concerning dryness integrated through the entire root zone is southern Duchesne County in Utah.
UCRB: It is recommended that D0 be extended in eastern Utah to include the remainder of Carbon County, extreme southeast Uintah County, south and central Duchesne County, and extreme east-central Wasatch County. Duchesne, Utah is showing similar precipitation deficits for the year to date to Price, Utah in Carbon County, which is currently in D0. Remotely sensed vegetative health and modeled root zone soils are consistent with short-term abnormally dry conditions in this region.
Eastern Colorado: Status Quo. D0 appears to be depicted in the correct areas.
**Disclaimer: The above recommendations are recommendations only, based on data, impacts, and
input from local experts. These recommendations are sent to the U.S. Drought Monitor author on Tuesdays. The USDM author
has sole discretion on final changes made in the region and can accept, reject, or modify the above recommendations
and may have additional modifications. Additionally, any recommendations discussed during the NIDIS webinars that are agreed upon
by the local experts and USDM author are still subject to change. Changes are final and official as of Thursday
morning, and can be viewed on the official U.S. Drought Monitor website.
Additional Drought Index Links: (will take you to an outside website)
Palmer Drought Severity Index for Climate Divisions Updated Weekly
WestWide Drought Tracker's PDSI Updated Monthly
Surface Water Supply Index