The two storms that hit Northern California between Friday and Monday morning brought the most significant rainfall to the region since mid-December. However, despite the ample rain, and from a half-foot to more than a foot of snow at some Lake Tahoe ski resorts, the National Weather Service Western Region reported that the Sierra Nevada snowpack saw “small increases.”
In late January, the California Department of Water Resources called the snowpack “dismally meager” after its snow measurement. The snowpack is counted on for about 30 percent of California’s water supply for agriculture and urban areas in the spring and summer, when it melts and fills reservoirs.
The U.S. Department of Agriculture Natural Resources Conservation Service reported Monday that the Sierra Nevada snowpack is "unusually low" for this time of year due to the warm, dry January. And the agency says the extreme drought in California may be "further aggravated by reduced streamflow" in other parts of the Western U.S.
Other states in the Western U.S. are experiencing below normal snowpack conditions too.
For the second consecutive year, Oregon’s mountains are experiencing record-low snowpack levels, according to the latest snow survey data from the USDA Natural Resources Conservation Service.
“It has been a warm and rainy winter in the Oregon mountains this year,” said Melissa Webb, a hydrologist with the NRCS Oregon snow survey team, in a news release. “Most of our sites in the Cascade and Siskiyou Mountains are measuring record low snowpack levels right now. There is grass growing in areas that are normally buried under many feet of snow. There is still time for improvement in our snowpack, but at this point, a full recovery is unlikely.”
Without significant snowfall in February and March, NRCS hydrologists say streams and rivers usually fed by snowmelt will experience well-below-normal flows this summer.
The National Weather Service in Sacramento reported that runoff from the weekend storms have brought “higher water levels in reservoirs,” but said those levels are “still below normal.” The NWS said rain totals from late Thursday through Monday ranged from 2-to-3 inches in the Sacramento area to 4-to-5 inches in the Santa Rosa area and 7-to-10 inches around Garberville.