Thanks to a strong inversion in the Northstate the last 2 days, we witnessed a huge spread in afternoon highs and overnight lows. Expect similar highs today.
Many mountain and foothill locations posted much warmer overnight lows than the valley.
We can thank the giant ridge of high pressure centered just a couple hundred miles west of the Northstate for the inversion and of course the warm afternoons.
For many locations in the Sacramento valley and basin and valley locations in the mountains the inversion will be harder to break in the afternoons. For folks in the northern tip of the Sacramento valley and towns sitting on the slopes of the mountains will see much warmer temperatures. This is happens because the cold air is dense,heavy and able to sit unmodified in more protected and low lying areas.
The ridge of high pressure will continue to sit on top or nearby the Northstate keeping us dry and warm in the afternoons through at least next Tuesday.