Low Spring Flood Threat Across California
The potential for flooding due to spring snowmelt in the California-Nevada River Forecast Center`s domain is below normal, due to much below normal snowpack.
Everywhere from the northern portions of the Klamath Basin down to the Tulare Basin in the Southern Sierra Nevada, is experiencing much below average snowpack.
December was a near normal month, but that was followed by a below average January, and a much below average February.
The February precipitation totals were one of the lowest on record for the state.
This has driven snowpack totals down to around 50% of average over California for the water year to date, and about 40% of average for April 1st.
Last year at this time, the precipitation totals were about 125% of average.
The seasonal runoff forecasts from April through July are very similar to the snowpack conditions.
Below normal runoff volumes can be expected throughout the Sierra Nevada.
The flooding potential during the Spring snowmelt season is below normal this season, due to the below normal snowpack. The potential for large springtime rainfall events, resulting in river flooding is still present and should be monitored throughout the Spring.
So yes, flooding in California remains a slight possibility due to the seasonal threat of heavy rainfall alone, or combined with snowmelt anytime during the spring.
Consult the AHPS Long Range Flood Risk Map for the latest point excedance probabilities:
For short term hydrologic forecasts and general water resources information, please see the CNRFC homepage at: http://www.cnrfc.noaa.gov.