Warming trend follows coldest air of the season; inversion season returns

SALT LAKE CITY (ABC4) — Happy Wednesday, Utah! After a chilly start to the work week, a ridge of high pressure is taking control of the West, and here in Utah, we get daytime highs to bounce back closer to seasonal averages.

Daytime highs are typically in the upper 50s and low 60s this time of year, with St. George in the low 70s, and you can expect the Wasatch Front to see temperatures climbing into the upper 50s for the midweek. We will see dry skies statewide, but you can also expect hazy sunshine. 

It’s been a while since haze has settled into our valleys, but Inversion Season is knocking on the doorstep of the Wasatch Front. This area of high pressure allows for a layer of warm air to act as a lid and trap cold air, and subsequently pollutants, on the valley floor. This haze will build, and it can lead to a decline in air quality.

If you are new to Utah, we need mixing of the air, or a storm, to clear inversion conditions. When it comes to temperature inversions, there are a few Utah factors that can make it worse including the geography of our mountains which limits the mixing of air in valleys, how long a ridge of high pressure holds on, snow on the ground and the solar angle. In this current situation, since it’s early inversion season, we should see a shallow inversion, but haze will become noticeable.

The Department of Air Quality is also forecasting “moderate air” for Davis, Salt Lake and Utah counties with the chance of elevated particulate matter for today. 

A weak front will cross Northern Utah late Wednesday into Thursday, bringing a minor wind shift, and will potentially help to mix up the air a bit to clear the haze. Overall, the building ridge high pressure is our major weather player, so we are not expecting any precipitation from the passing of this front and very little temperature change.  As the ridge of high pressure slides east, we should see a steady warming trend of a few degrees each day. Highs will rebound back into the 60s by this weekend with highs remaining in the 70s for the next week across SW Utah.

With this pattern in place, we expect clear skies and dry conditions for Halloween statewide. Trick-or-treaters get a treat with highs hitting the low 60s along the Wasatch Front and upper 70s for Washington County.  Our Friday evening will feature mostly clear skies with temperatures going from the 70s into the 60s for southern Utah and temps falling from the 50s into the 40s across northern Utah as the little ghosts and goblins head out.

We will start out November with similar conditions thanks to that high pressure. Slight above average warmth and dry skies expected for the first week of the month. 

While we are facing a pleasant weekend, don’t forget this weekend is the time when we “fall back” with our clocks. Remember to set those clocks back an hour before you head to bed Saturday night. Daylight Saving Time officially ends Sunday morning at 2 a.m. We gain an hour but will get darker earlier, so get ready for those 5 o’clock hour sunsets!

We’ll keep you posted on the latest developments in our 4Warn Weather forecast both on-air and online, we are Good4Utah!