June 13, 2020 – Cooler temperatures, breezy winds, and a chance of rain showers north of I-80. Dry and warmer weather Sunday on through the week.
Discussion
The back end of the upper trough that brought locally heavy showers and thunderstorms yesterday is currently over NorCal, with the main vort max over western Nevada. Convective activity overnight over the area has died down considerably, with just a few lingering light showers. Some mainly morning showers are possible for the northern Sacramento Valley and adjacent mountains. By afternoon, a slight chance will be mainly over Shasta County. Instability and lift are limited, so not expecting much convection today.

Dry and cool weather are expected elsewhere. Some morning stratus clouds are expected over the Delta and into the Sacramento metro area. Afternoon highs will be even lower than yesterday, especially over the northern Sacramento Valley. Temperatures are expected to peak in the mid to upper 70s across the Valley. Breezy onshore flow continues, though not as strong as yesterday. southwest to southerly winds will be breezy, gusting up to 20 -25 mph in the morning, a little lighter in the afternoon.
Drier and warmer weather returns on Sunday as the upper low exits to the east and high pressure ridging builds in from the west. Valley highs in the mid to upper 80s are expected Sunday afternoon. Eastern ridging tries to build in, but troughing to the north will keep the pattern relatively flat, with near normal highs.
Extended Discussion (Wednesday through Saturday)
Hot and dry weather expected as NorCal is situated downstream of eastern Pacific ridging. High temperatures are expected to be in the mid 90s to just above the century mark across the Central Valley with moderate heat risk through the second half of next week.
Expect lowering humidity levels and drying fuels with no precipitation in the forecast. Light to moderate northerly winds expected at times through the Central Valley.
