5/17/2021 Forecast Update
FORECAST SUMMARY:
FORECAST SUMMARY: Monday, May 17th, 2021 through Friday, May 21st, 2021
OZONE: 8-Hour average Ozone concentrations are expected to range from Good to Moderate through the forecast period.
PM-2.5: 24-hour average Fine Particulate concentrations will also range between Good to Moderate.
FORECAST DISCUSSION:
A warming trend will be seen this week but there are also on and off chances for precipitation. The expected forecast has high pressure dominating at the surface, and an upper-level ridge over the eastern U.S. Monday retrogrades west. This ridge produces south/southeast winds early in the week; however, the flow becomes more southwesterly around mid-week. The southwesterly flow at the surface and upper levels brings increased dew points, along with warmer temperatures. Disturbances moving along the upper-level flow keeps scattered precipitation chances through the period.
As for air quality, I feel we’ll have a mix of Good and Moderate levels of both ozone and fine particulate through the week. Areas that are precipitation free and have more afternoon/evening sunshine will have the greatest chances for Moderate ozone. The threat for Moderate ozone will also increase past mid-week when winds become more southwesterly in nature. By Thursday and Friday, I expect more widespread Moderate ozone readings. We will send a forecast update Thursday if our thoughts on the current forecast changes to where we feel ozone into the USG range is a possibility Friday.
EXTENDED FORECAST:
Extended forecast models show warmer temperatures through the coming weekend, but there are some questions on a frontal boundary, its associated cloud cover, and if/when precipitation will be seen. With uncertainty on the extended weather conditions, a forecast updated will be done Friday to better detail air quality levels for the weekend into early next week.