Diminishing winds, rising temperatures through the remainder of the week

February 11, 2020 – Breezy northeast winds continue today. Dry this week except a slim threat of showers over mainly the mountains beginning late Thursday and continuing into the weekend.

Discussion

Clear skies cover the region early this morning except for a few cirrus clouds dropping down from the north. A tight north to east surface pressure gradient remains in place across NorCal, though the northerly gradient is a bit lower compared to 24 hours ago and the east gradient has begun to slacken slightly since Monday evening. Still see quite a few northerly gusts of 15-25 mph in the Sacramento Valley, especially along the west side and north end of the valley.

Across the foothills and northern Sierra, localized gusts of 35-45 mph are still occurring, but these will gradually taper off during the morning. Gusts approaching 50 mph are currently occurring near the mouth of the Feather River Canyon where winds will likely peak early in the morning.

Warm and dry weather will continue across the region the next few days. Looks like a favorable bet that highs today will exceed NBM guidance with a few daily records possible, and have adjusted accordingly. Winds will decrease this afternoon, but breezy conditions will continue into this evening and linger into Wednesday across a good chunk of the Sacramento Valley, and locally across the foothills and mountains.

Precip prospects for the first system later Thursday into Friday are looking dismal with only a few sprinkles or light showers in the offing for the mountains. The main effect will be to bring slightly cooler temperatures for the end of the week.

Extended Discussion (Saturday through Tuesday)

Upper level ridging is expected to build over California on Saturday. Ensemble guidance continues to show a trough sliding southeast along the flow and clipping California late Saturday through Sunday. This will bring a slight chance of precipitation to interior Northern California, mainly limited to the foothills, mountains, and northern Sacramento Valley. Only light accumulation is forecast with this system as the heaviest precipitation is likely to remain well north of California. Confidence remains low on precipitation timing and amounts with this system due to inconsistencies between ensemble models.

As the trough axis deepens to the east of California and the Pacific ridge builds to the west, northerly winds will increase Monday through Tuesday. Location of the trough axis will depend on the strength of winds. As of now, winds are not expected to be particularly impactful. However, will have to keep an eye on how the models resolve the pattern as we get closer. There could be some lingering mountain showers Monday depending on the position of the trough axis. Otherwise, dry weather expected through midweek.