The combination of strong winds and low relative humidity prompted the SPC to forecast elevated to critical fire weather potential across parts of the Upper Midwest on 29 April 2018. A Mesoscale Domain Sector was positioned over the region, providing data at 1-minute intervals — and “Red” Visible ( 0.64 µm ) and Shortwave Infrared ( 3.9 µm ) imagesrevealed the smoke plumes and thermal anomalies or “hot spots” (black to yellow to red pixels) associated with some of these larger fires. The most prominent fires were located in southeastern Manitoba later in the day (including the largest, which was listed as Out of Control).

On the Visible images, also note the hazy signature of blowing dust that developed from the northern Red River Valley of North Dakota and Minnesota into southern Manitoba — with winds gusting in excess of 50 knots, the surface visibility dropped to 3 miles at Grafton ND (KGAF) and Winnipeg International Airport (located just northwest of station CXWN in southern Manitoba).