Winds gusting over 40 mph across southern Saskatchewan during the afternoon on 11 October 2022 resulted in lofted aerosols from localized regions becoming long and narrow plumes carried downstream into northeast Montana and northwest North Dakota. GOES-East 5-min Geocolor imagery captured these light gray colored plumes quite well as they were fairly opaque and their appearance contrasted nicely with otherwise brown/green surface (Fig 1). From the Geocolor alone, one could deduce these plumes were likely emanating from or near a lakebed. A quick look at the source lat/lons on google maps also reveals lakebeds.
Viewing these sources in recent high resolution Sentinel-2 True Color Imagery, we see from the high reflectance signature that these are indeed mostly to fully dry lakebeds, confirming the source of the lofted aerosols to be dry lakebed sediments (Fig 2 and 3).
Due to drought conditions across the region over the past few years, there has been a drying of saline lakes in the area resulting in these types of blowing salt-dust events. As a result, there have been numerous highway accidents due to reduced visibility, and cattle are getting sick and dying due to contamination of drinking water. This article from a month ago discusses an event that caused a multi-vehicle pile-up.
Strong winds continued across the region the next day (Oct 12), and resulting blowing dust salt was captured in GOES-East Meso-2 1-min sector (Fig 4).
Viewing a zoomed out, full disk version of GOES-East Geocolor, we notice smoke wrapping around a low as it advances east across Canada (Fig 5). Where did this smoke come from?
Investigation of Day and Night VIIRS Geocolor Imagery (with semi-transparent Fire Temperature RGB overlay) from the past few days captures the burst of a large wildfire complex in Northwest Territories, Canada (Fig 6). VIIRS Geocolor includes the real-time DNB light information as well, which provides detailed info about the active fire areas during the evening that wasn’t quite captured in the thermal bands. The image combination depicts both the actively burning wildfire as well as the smoke plume in great detail. This complex and other nearby fires were the source for the broad smoke plume observed wrapping around the Canada low on the 11th. This image combination can be viewed on the Polar SLIDER here.
Viewing the nighttime DNB NCC product alone during the past few nights, we see the light associated with the fire increase dramatically during the night of the 9th-10th (Fig 7).
Bill Line, NESDIS/STAR
Kyle Ziolkowski (ECCC/MSC/Storm Prediction Centre – Winnipeg)
Carl Jones (NWS/FGF)
Steve Miller, Curtis Seaman, Jesse Turner (CIRA).