April 29, 2019 – Cooling trend early this week with temperatures near or a little below average by Tuesday. Dry conditions except for a chance of showers or isolated thunderstorms over the foothills and mountains through Tuesday.


Clear skies across most of the region early this morning as debris cloudiness left over from Sunday’s convection has finally dissipated, and clouds associated with the deformation zone to the north of the SoCal low cover just the far southern edge of the forecast area. Current temperatures range from the 30s in the mountain valleys to mainly the 50s to lower 60s elsewhere.

Weak trough remains over NorCal and may result in a few showers and thunderstorms over the northern Sierra south of Lake Tahoe in the afternoon. Stronger short-wave moves down from the north and will result in a better chance of showers over the foothills and northern Sierra late tonight and Tuesday.

Synoptic cooling from the upper trof will result in slight cooling today. More noticeable cooling is expected Tuesday with increased cloudiness and temperatures lowering to slightly below average for late-April.

Upper ridging builds back into NorCal on Wednesday leading to an upward trend in temps that continues through the rest of the work week.

Extended Discussion (Friday through Monday)

Upper ridging moves through on Friday for dry weather. Closed upper low in EPAC then progresses towards the Central CA coast Saturday, shifting inland Sunday. Unsettled weather expected over the weekend with showers over the mountains Saturday, spreading into the foothills and possibly into portions of the Central Valley on Sunday. Models differ with track of upper low by Monday, but will continue to advertise the threat of showers over mountains of Western Plumas county and the Northern Sierra Nevada Monday. Cooling trend expected through the extended forecast period with high temps near to a few degrees above normal by day 7.