The National Weather Service has increased its thunderstorm threat for Tuesday and Wednesday of this week, adding that thunderstorms coming to the interior of Northern California could bring “heavy rain, ponding of water, hail, and an isolated tornado”.
The alert from the National Weather Service currently reads:
• Snow and gusty winds will likely bring travel delays and chain restrictions over the Sierra
• Thunderstorms could bring heavy rain, ponding of water, hail, and an isolated tornado
• High: Rain and Snow Tuesday into Thursday
• Medium: Threat of thunderstorms Tuesday and Wednesday (increased)
Timing and Strength
• Precipitation spreading across interior Northern California Tuesday, with periods of precipitation through Thursday. Heaviest precipitation Wednesday into Wednesday night.
• Precipitation totals up to an inch in the Valley, locally higher with thunderstorms. 1 to 3 inches possible in the mountains. (see attached graphic)
• Snow totals greater than 1 foot possible above 5500 ft, with accumulations greater than 2 feet possible along the highest Sierra peaks. Snow levels initially above 6500 ft Tuesday will drop to around 4000 ft by Wednesday. (see attached graphic)
An upper-level trough will move through Northern California Tuesday into Thursday bringing a cooler airmass and breezy southwesterly winds along with a threat of precipitation. Thunderstorms could form with these systems Tuesday and Wednesday, and bring locally heavy rain, hail, gusty winds, and possibly an isolated tornado in the Valley and Sierra foothills. Additional precipitation is possible through the end of the week with more systems coming through the area, including a potentially strong storm system this weekend. The precipitation received will offer some short term gains but will not end the drought.”
For the latest updates on watches and warnings, please visit our weather page.