04/12/2023 Forecast Update

FORECAST SUMMARY: Wednesday, April 12, 2023, through Thursday, April 13, 2023

OZONE: 8-hour average ozone concentrations are expected to be mostly Good to Moderate through the forecast period.

PM-2.5: 24-hour average Fine Particulate concentrations are also expected to be mostly Good to Low Moderate through the forecast period.

FORECAST DISCUSSION:

This has been an interesting week to track in terms of Air Quality.  We do not usually encounter ozone problems during April, especially the first half of April.  However, this week has proven to be an exception.

We have been seeing an increase in ozone production, each day, this week. Yesterday, we had some monitors in excess of 70 ppb for the 1-hour average.  What has saved us, so far, is the upper atmosphere is still cold, low dew points, limited daylight hours, and a brisk wind to keep the atmosphere well mixed.  If those factors were not in play, we would likely be looking at elevated ozone and be issuing Air Quality Advisories.

Thursday will most likely stay in the Moderate range for the reasons stated above.  However, Friday may be more challenging.  As the big, slow moving, high pressure system that has been giving us this great weather moves to the east, winds become a bit more southerly and not quite as strong.  Even with the early April limited hours of sunlight, skies will stay clear allowing maximum solar energy to get through.  Add the fact that each day has provided more ozone to the background to prime the next day’s ozone production.

As such, the forecast will be updated Thursday morning.  Friday should be the last day of concern as a low pressure system will approach on Saturday and move through the region during Sunday.

EXTENDED FORECAST:

Air Quality should be mostly Good begin the next work week.

Next Forecast update: Thursday, April 13, 2023