U.S. Air Quality

Critical fire weather expected over northern Plain States

Smoke from wildfires in the Pacific Northwest continue to emanate light to moderate smoke, exacerbating air quality conditions. Fires along the US-Canadian border are also contributing to the smoke layer today, as smoke was reported stretching from the upper Plains through Great Lakes states (top left, courtesy HMS). In addition, today's MODIS true color imagery superimposed with AOD indicates elevated AOD over the Dakotas, near the elongated smoke layer (top right). Unfortunately, ongoing drought and a favorable atmospheric pattern increases fire concerns across the northern Plains. The National Weather Service Storm Prediction Center's (SPC) Fire Weather Outlook forecasts critical fire weather conditions over the next few days as warm temperatures, low relative humidity, and southerly surface winds strengthen (bottom left). The trigger for this favorable fire weather is a strengthening surface low pressure over the area which will act to tighten the gradient between higher pressure to its east, all of which intensify boundary layer winds (bottom right, courtesy HPC).