May 16, 2018 – Afternoon and evening thunderstorms possible over higher terrain for much of this week with a chance of showers and isolated thunderstorms across the entire region today.
Discussion
Partly cloudy skies cover the region early this morning as the next low approaches the coast near the Bay Area. A few showers linger to the southwest of Redding. Current temperatures range from the mid to upper 30s in the mountain valleys to the 50s to lower 60s across the Central Valley.
Scattered showers and perhaps a few thunderstorms are expected to begin developing this morning, mainly to the north of the track of the upper low. Forecast soundings indicate sufficient moisture and elevated instability for shower development once lifted with greater activity transitioning to the mountains during the afternoon.
Upper low will shift into Nevada on Thursday and into the Rockies by the weekend. Weak disturbances and instability will rotate south along the backside of the low through this period with afternoon showers and thunderstorms continuing over the mountains.
High temperatures will be slightly below average through Thursday, but will warm slightly late in the week.
Extended discussion (Sunday through Wednesday)
Upper low deepens and digs along the CA coast Sunday into Monday then tracks across SoCal into the Great Basin Tuesday. Another upper trough approaches Wednesday. This will keep a threat of showers and afternoon thunderstorms over the mountains. High temperatures will be near to slightly above normal through the extended period.