Posted: Apr 11, 2013 8:27 PM by MTN News
Streamflow forecasts for April show a decline in parts of every Western state according to USDA's Natural Resources Conservation Service water and climate experts.
Because of the lower forecasts NRCS hydrologists predict reduced spring and summer water supply for much of the West.
This month's forecast is especially important because there probably won't be significant snow accumulation after April 1, according to hydrologist Tom Perkins.
"April is usually the endgame. We're not likely to make up this deficit. Snowpack is not good. Reservoir carryover is not good," said Perkins.
Although other parts of the country got more snow, it didn't have impact in the western mountains, he said.
"What fell in the West didn't really amount to much," Perkins said. "New Mexico, Nevada and Colorado are especially vulnerable because their reservoirs are at low levels due to sustained drought conditions."
Water resource managers face difficult decisions due to this shortage, he said. Western states should prepare for potentially increased vulnerability to forest and rangeland fires and mandatory water restrictions. In addition, wildlife that depends on surface water is going to suffer.
There are a few exceptions to the dry forecasts. The North Cascades - including Washington and Western Oregon - and the headwaters of the Missouri and Columbia Rivers are near normal. "For the rest of the West," Perkins said, "there is no silver lining. I think it's going to be a long, hot, dry summer."
In addition to precipitation, streamflow in the West consists largely of accumulated mountain snow that melts and flows into streams as temperatures warm into spring and summer.