Given our current state of drought, many are wondering: How does this winter’s rainfall stack up to normal rainfall?
Long-term rainfall 
data indicate that, on average, Napa Valley receives 16% of annual rainfall during the month of February.
Based on the data collected from 15 Napa County ALERT rain gauges during February 2016, the Napa Valley received only 4% of the annual average. In total, since October 1 we have received 61% of our mean annual precipitation, well below the average of 74% for this time of year. Rainfall depths recorded at these stations during February ranged from 0.71 inches on Mt. George to 2.41 inches on Mt. St. Helena. Rainfall totals for Water Year 2015-16 range from 12.45 inches on Sugarloaf Peak at the southern extent of the eastern hills to 34.60 inches on Mt. St. Helena.
A dry February has not helped our water situation, but here in early March a large winter storm is already forecast to bring much-needed rainfall to the Valley. Maybe this will be the start of a wet March that will put us into above-average territory.
– Paul Blank, Senior Hydrologist, paul@naparcd.org