US Drought Monitor September 22, 2015
West Drought Monitor September 22, 2015
Colorado Drought Monitor September 22, 2015
Click here to read the current update. Here’s an excerpt:
Warm dry conditions have continued across much of eastern Colorado, while the mountains have seen near average precipitation so far this month. Drier conditions have resulted in declining soil moisture levels, but overall evapotranspiration rates are below average for the season, and pasture conditions and harvest yields are reportedly good. Water providers are also reporting increased demands during August and September, however system-wide storage levels remain above average and providers have no immediate concerns.
The abnormally dry conditions along the eastern plains and Front Range are not serious enough to require action.
The Colorado Drought Mitigation and Response Plan was formally deactivated by Governor Hickenlooper on September 15, 2015 due to improved conditions. Additional information on this can be found at http://cwcb.state.co.us/water-management/drought/Pages/DroughtResponse.aspx Statewide water year-to-date precipitation is 94 percent of average, a slight decline since last month. Statewide August received only 62 percent of average precipitation while September to-date have seen only 71 percent of average. Generally, the west slope has seen greater precipitation than the eastern plains. August temperatures were above average by 1.6 degrees Fahrenheit, with the warmest temperatures along the southern Front Range. September to-date has seen slightly above average temperatures on the west slope and well above average temperatures on the eastern plains. Warmer temperatures typically drive up demand for irrigation water during the growing season. Reservoir Storage statewide is at 115 percent of average as of September 1st. The Arkansas has the highest levels in the state at 145 percent of average. The Upper Rio Grande has the lowest storage levels at 92 percent of average, this is also the only basin with below average storage. However, the Rio Grande levels are 31 percent greater now than this time last year. The Surface Water Supply Index (SWSI) is highly variable across much of the state. The majority of the sub-basins remain near normal, however most have seen declines over the last month. Portions of the South Platte and Arkansas have abundant supplies due largely to reservoir storage levels. The greatest declines have been in the Colorado and Yampa River basins. The state has recently complete an automation tool for the SWSI index and a revised detailed monthly report can be found at http://water.state.co.us/DWRDocs/Reports/Pages/SWSIReport.aspx El Niño has gained strength over the last few months and continues to be forecasted as a strong event, which is likely to persist through winter. Strong El Niño events typically result in above average precipitation in the fall, but not necessarily in the winter, with the highest risk of a dry winter for the northern and central mountains. The best combination would be for the El Niño to weaken over the winter, and then come back strong in spring.