@CWCB_DNR/@DWR_CO: November 2018 #Drought Update

From the Colorado Water Conservation Board (Taryn Finnessey/Tracy Kosloff):

In response to persistent and prolonged drought conditions throughout the southern half of the state and along the western border, the Governor activated the Colorado Drought Mitigation and Response Plan for the agricultural sector on May 2, 2018, additional counties in northwest Colorado were added in September; information can be found HERE

The 2018 Water Year (which ended on September 30) was the warmest and second driest in 124 years of records for the state of Colorado. Water Year 2019, which began on October 1st, has seen above normal precipitation and below average temperatures across most of the state. This is the first time in over a year that the statewide average monthly precipitation was above average and monthly temperature was below average. Recent precipitation gains have helped to relieve some drought conditions in Southeastern and Northwestern Colorado; and have led to a good start to the snowpack accumulation season. Cold temperatures and above average precipitation has continued in the first half of November, however, precipitation has not benefited southwestern Colorado as much.

■ As of November 13th, exceptional drought, D4, continues to affect southern Colorado covering 13 percent of the state, extreme drought, D3, covers 21 percent of the state; severe drought 21 percent and 12 percent is classified as moderate drought. An additional 17 percent of the state is currently experiencing abnormally dry conditions.

■ An El Niño watch remains in effect, with a greater than 80 percent chance of an El Niño developing by the end of the calendar year, which could bring an increased chance of wet extremes for southern Colorado.

■ SNOTEL water year to-date precipitation statewide is 124 percent of average, but ranges from 92 percent of average in the Southwest basins to 170 percent of average in the South Platte River Basin. The Arkansas is at 163 percent, while the Colorado is at 134. The Rio Grande and Yampa- White are at 115 and 113 percent of average, respectively; while the Gunnison is at 96 percent.

■ Reservoir storage, statewide is at 81 percent of normal, with the Arkansas, Rio Grande, Yampa-White, and South Platte all above 90% of average for the end of October. Storage in the Colorado River basin is 89% of normal. The Southwest basins of the San Miguel, Dolores, Animas & San Juan, and Gunnison are now at 55 and 53 percent of normal, respectively.

■ Ridgway Reservoir is currently at its lowest point since it was first filled. Recovering from the rapid reservoir declines seen during the summer of 2018 will likely take some time. As of November 1, reservoir storage levels vary widely from near record high to near record low levels, with the Colorado, Gunnison and Southwest basins all below normal.

■ Long term forecasts indicate an increased likelihood of above average temperatures statewide November through January. Southwestern Colorado is forecast to continue to benefit from moisture as a result of the developing El Niño and has an increased likelihood of above average precipitation over the same time period.

■ Water providers are seeing decreased demands consistent with typical winter demands.

■ Fall moisture has helped with winter wheat planting and limited prevented acres were reported.

Widespread precipitation in October helped to alleviate drought conditions in some areas. Many areas of the state saw more precipitation in October than they saw collectively in the first half of Water Year 2018.

Snowpack is off to a good start with most areas of the state seeing above average accumulation in October and the first half of November.

Despite recent precipitation, Western Colorado is still dealing with severe, extreme and exceptional drought. Continued above average snow accumulation may help to alleviate these conditions as the winter progress and will be closely monitored.