Justin’s Monday Night Forecast Discussion:
The below freezing nights keep stacking up with a super-strong ridge of high pressure dominating the Northwest and that’ll keep on keeping on for tonight. Patchy valley fog will fill in late tonight and with lows expected to get into the upper 20s again, be on the lookout for another round of freezing fog at your morning commute.
The ridge is exceptionally strong for this time of year and placement (partially because of the nose-dive the jet stream is taking across the Eastern US but that’s another discussion) so anything that tries to get through, a la storms, get split into two or just outright blown to pieces. What that means for us is multiple days of foggy starts in the valley, but partly sunny to mostly sunny finishes by the afternoon. Tomorrow may hold onto some fog into the early afternoon because of the light surface winds, but outside the valley (mountains and coast) will see ample sunshine. Highs still cool though, in the mid 30s in the foggy valley, upper 40s at the coast, 20s to 30s in the mountains.
While it will keep our January unusually dry, the high also compresses the air creating what’s called an inversion. That’s when colder air gets trapped under a warmer pocket of air aloft. This “lid” traps pollutants close to the ground and the light winds don’t allow the air to mix, thus our air quality suffers. It’s something we’ll monitor throughout the week as this dry pattern holds. You can check out the expected Air Quality Index or AQI each day here: LRAPA
Have a great Tuesday!
Chief Meteorologist Justin Stapleton
Also, do you have a question for the weather team? You can “Ask The Meteorologist”! I’ll be answering YOUR questions Wednesday night at 6. Click here to submit your question: Ask The Meteorologist