April 26, 2019 – Mainly Fair skies and above normal temperatures the next several days. A slight threat of showers over the northern Sierra early next week and over the entire Sierra Cascade crest next Tuesday. Dry with above normal temperatures the remainder of the week.
Slightly cooler temperatures are expected today as the high pressure ridge over the west coast moves east of the forecast area. It now looks like any precipitation associated with a weak through passing through the Pacific Northwest today will remain north of the CWA.
The forecast remains dry going into the weekend with only minor changes expected in daytime highs which are expected to remain about 10-15 degrees above normal. A closed low pushes towards the SoCal coast Sunday in conjunction with a trough moving across the northern portion of the state. Diffluent flow aloft may bring a threat of afternoon or evening showers over the Sierra Sunday although northwest flow aloft should limit the northward extent of this shower threat to south of Tahoe.
The SoCal upper low is forecast to push through the south state on Monday. This will likely bring scattered showers to that portion of the state but most of the north state should stay out of its influence. Much of the CWA will see a little cooling Monday especially the southern most areas closest to the low center. A few showers may make it into the northern Sierra but again remaining south of about Tahoe. Even with the slight cooling Monday, daytime highs going into the extended period are still forecast to remain about 10 degrees above season normals.
Extended Discussion (Tuesday through Friday)
Models show short wave trough brushing across NE portions of CA on Tuesday bringing a slight chance of showers to the mountains of Shasta and Western Plumas counties and Northern Sierra Nevada. Main impact for remainder of interior NorCal will be some synoptic cooling. Broad troughing remains over the area into Wednesday morning then shifts east as EPAC ridge begins to build inland. Dry with warming temperatures forecast through the remainder of next week.