A few lingering showers and thunderstorms over the mountains today, otherwise dry weather returns. Warmer temperatures through Thursday, then cooling returns for the weekend.
Discussion
Radar shows a few lingering showers early this morning over the mountains of Shasta County and across the Sierra to the east of Sacramento. Elsewhere, skies remain partly to mostly cloudy over the region as the closed low moves slowly northeastward across the southern Sacramento Valley. Current temperatures are considerably cooler compared to 24 hours ago (5-15 degrees lower) and are mainly in the 40s and 50s in the mountains, and 60s to lower 70s across the Central Valley.
The low will open and lift quickly off to the northeast into the northern Rockies today as another closed low approaches the PacNW. Enough moisture/instability lingers for a few showers and afternoon thunderstorms over the mountains today before drier and more stable conditions return beginning Wednesday as short-wave ridging moves overhead.
Temperatures will rebound today, but will still be below average. Hot weather returns Wednesday and Thursday as temperatures return to average, or slightly above. Another trough is forecast to develop off the coast by the end of the week leading to cooler temperatures starting Friday.
Extended Discussion (Saturday through Tuesday)
Closed upper low modeled to linger off the West Coast through the weekend into early next week. Models differ with how quickly it progresses with GFS shifting it inland over the PacNW Tuesday. All support southwesterly flow aloft over interior NorCal with increased onshore flow. This will result in dry weather through the extended forecast period with high temperatures near to below normal.