US Drought Monitor October 8, 2013
to go to the climate dashboard. Scroll down for the new stuff. Here’s an excerpt:
September Precipitation and Temperatures, and Current Drought
September ended the 2013 water year on a very wet note across the region, with most of the region receiving at least 200% of normal precipitation, and only a few small areas seeing drier-than-normal conditions Western US Seasonal Precipitation. The last month with comparable wet anomalies across the region was December 2007. A persistent rain event from September 9th–17th, caused by a late monsoonal surge from the south reinforced in eastern Colorado by very moist upslope flow, brought most of the month’s precipitation, including extraordinary totals for Boulder, Colorado (9″ in 24 hours; 17” in seven days) and the surrounding area. (See the WWA’s preliminary assessment of the Front Range rain event and the severe flooding it caused.)
Other areas with over 5” of precipitation for the month included far southeastern Wyoming, south-central Utah, the Uinta Basin in northeastern Utah, the southeastern Yellowstone Plateau, and the San Juans in southwestern Colorado.
With this late surge, the final HPRCC Water Year Precipitation map Western US Seasonal Precipitation for 2013 showed that the previously scattered areas with above-average precipitation since October 1 have enlarged and merged, covering perhaps one-third of the three-state region, with the wettest areas in northeastern Colorado, southern Utah, and northern Wyoming. But, as in the 2012 water year, most of the region still ended up drier than normal.
Despite all the precipitation, the temperatures in SeptemberWestern US Seasonal Precipitation were warmer than average across the region, except in parts of western Utah and western Colorado. Most areas were 1–6°F above monthly average temperatures for September.
The latest US Drought Monitor, representing conditions as of October 1 Modeled Soil Saturation Index, shows significant and widespread improvement in the persistent drought conditions, by one to three categories, compared to one month ago. The most dramatic improvements were in northeastern Colorado, where up to D2 drought conditions were brought to normal, and in southwestern Colorado, where D3 drought improved to D0 Modeled Soil Saturation Index. The proportion of Colorado in D2 or worse drought dropped from 60% on September 3 down to 12% on October 1; in Utah, 54% down to 16%; and in Wyoming, 48% to 22%. Region-wide, the overall drought extent and severity is now lower than it has been since April 2012.