It was a slightly cooler day for northern California today, but a more significant cooling is arriving tomorrow, along with a slight chance for showers and thunderstorm over the mountains of northwest California. Tonight will be a mostly clear to clear night with a few areas of smoke and mild lows. Lows will range from the 40s and 50s in the mountains to mainly the 60s in the foothills and valley. Wednesday will be a mostly sunny to sunny day with breezes developing along with isolated showers and thunderstorms in the far north. Highs will be cooler however, staying mainly in the 80s and 90s for both mountain and valley locations.
The trough of low pressure responsible for the cooler and breezier weather won't stay over California very long. We'll still have lingering breezes and slightly cooler than average weather on Thursday, but the temperature trend will already be heading back upward. Another ridge of high pressure will control our weather pattern Friday through this weekend. That will clear our sky and heat our air back to above average levels through early next week. Another trough will begin pushing our way next Tuesday and Wednesday, ushering in another cooldown. Highs will rise back into the 90s and lower 100s from the mountains to the valley.