A dry January has shrunken the snowpack across the Sierra Nevada, a vital water resource for many California farms and cities.
The state Department of Water Resources conducted field measurements of the snowpack at various locations on Tuesday and found it to be 93 percent of average for the date. This comes after heavy snows in December had the snowpack at above average conditions.
The reversal is due to a lack of storms moving into Calfornia during virtually the entire month of January, normally the wettest month of the year. Precipitation across the Northern Sierra, a region crucial to snowpack water storage, has been only 13 percent of the January average.
While not yet a warning of drought conditions or water shortages to come, that could change if the balance of winter is also dry.
"Relatively dry weather this month is once again a reminder that the weather is unpredictable and we must always practice conservation," DWR Director Mark Cowin said in a statement.
November and December each delivered about 200 percent of normal precipitation in the Northern Sierra. As a result, water storage reservoirs are in good condition for this point in the year. Folsom Lake on the American River currently holds 110 percent of average water volume for the date, while Shasta and Oroville reservoirs are at 111 percent and 113 percent, respectively.