|August 20 Lightning Map: 3,458 down strikes recorded in the past 24 hours|
Numerous new fire starts were reported yesterday, with some developing into major incidents. New starts are likely throughout the next week, with lightning activity predicted to intensify today. On many National Forests the lightning alert level (LAL) is at 4 out of a possible 5, with resources beginning to be stretched thin. (A definition of LAL levels can be found here.>)
Red flag warning in effect until Wednesday night.
The low is expected to gradually move to the northeast this afternoon and be off the Bay Area coast on Wednesday and move inland across Northern California on Thursday bringing instability and moisture over interior Northern California. Isolated to scattered showers are expected to continue through Thursday especially in the afternoons and evenings with daytime heating. The threat will diminish from south to north as the low moves off to the northeast Wednesday into Thursday. Although the gfs is slower in the bringing the low inland and a little further west with the track compared to the ecmwf and nam. So there is some uncertainty in how quickly the thunderstorm threat will linger in interior Northern California on Thursday. The current forecast slows the timing a little and lingers a chance of showers and thunderstorms over the northern mountains into Thursday evening. The red flag warning for possible abundant lightning and gusty winds over the foothills and mountains continues into Wednesday night/Thursday morning at this time. My need to extend it over the Shasta Trinity Forest during the day Thursday if the low is slower. The thunderstorms may also bring heavy rain and small hail. Mostly sunny skies and warmer temperatures along with southwesterly flow are expected on Friday as the low continues off to the northeast.