Phoenix Weather Report for Nov 30th, 2020
Forecaster: Henz, D
Hopefully, everyone had a wonderful and safe Thanksgiving weekend. We’ve reached the end of November with no rain to show and spent the better part of the month with very warm temperatures.
Today’s weather will be sunny with light winds for the Greater Phoenix and Gila Bend area. Temperatures are expected to reach 73 degrees today. Tonight will be clear skies with a low of about 42 degrees. Winds light and variable.
Looking at the big picture, a weak disturbance will move across the region today bringing some passing high clouds but otherwise go unnoticed. Moving ahead, a more robust disturbance will dig south into the Great Basin region by midweek, which will likely bring some increased breezes to the region and lower temperatures closer to seasonal normals (upper 60s). Otherwise, plan on quiet weather conditions as we move into the start of December.
For tomorrow plan on a return to clear skies across the region. Daytime highs will warm back into the 70˚F-72˚F range around the Valley. Variable winds will hover in the 3-8mph range with localized afternoon gusts around 10-15mph. There will be little change in the forecast for Wednesday with sunny skies and afternoon highs around 70˚F, before cooler temperatures and increased breezes for Thursday and Friday. We’ll have more on this in the coming days.
Air Quality Forecast
ADEQ Meteorologist: M. Pace
Over the weekend, Phoenix saw PM2.5 (fine particulate matter) exceed the federal health standard for the first time since New Year’s Day. However, this only occurred at monitoring sites just to the west of the Phoenix metro area. Elsewhere around the Valley saw PM2.5 in the Moderate or Good Air Quality Index (AQI) category.
Unfortunately, as mornings continue to get colder, the potential for elevated PM10 (dust) and PM2.5 levels will grow. This is because of the “inversion,” which is a layer of warm air just above the ground that acts as a lid to trap particulate matter (PM) near the ground. Learn more about the inversion HERE.
The good news for this week is that decent winds are forecast to be present on and off, which will help to limit PM levels. For instance, this morning breezy easterly winds are already helping to keep PM2.5 levels lower. Winds will last through the morning and into the afternoon. Winds are also forecast to increase out of the northeast on Thursday morning and remain elevated through Friday. This should have a similar effect as well.
For the most part, PM10 and PM2.5 are forecast in the Moderate AQI category this week. And as typical, highest PM levels are expected in the industrial areas south/southwest of the Phoenix metro area.
