Two PyroCbs in Yukon

On 25 June a pyroCb formed at 23:45 UTC in Yukon (63.1 N 136.1 W). Also, another pyroCb formed on 26 June at 02:15 UTC at 62.8 N 137.8 W. GOES-15 detected the smoke plume and pyroCb cloud, as well as the fire hot spot. Starting at 21:45 UTC on 25 June, the animation below shows visible (.63 μm) on the left and shortwave IR (3.9 μm) on the right (click image to play animation). In the shortwave IR images the red pixels indicate very hot IR brightness temperatures exhibited by the fire source region.

GOES-15 0.63 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

GOES-15 0.63 μm visible (left) and 3.9 μm shortwave IR (right) images (click to play animation)

Also, using GOES-15 10.7 μm IR channel the cloud-top IR brightness temperature could be found. The animation below, starting at 21:45 UTC on 25 June, shows the brightness temperature of the first pyroCb reaching -56.2ºC (yellow color enhancement) around 01:45 UTC on 26 June. From the Whitehorse Sounding this put the cloud top at 11 km. In addition, the loop shows the second pyroCb reaching around -50ºC around 4:30 UTC (indicated by yellow color enhancement).

GOES-15 10.7 μm IR images (click to play animation)

GOES-15 10.7 μm IR images (click to play animation)

On 26 June OMPS Aerosol Index (AI) images were useful to see the transport of the smoke. From the AI image (below; courtesy of Colin Seftor and Rene), it can be seen that the smoke was being transported eastward. Region 1 tracks back to the Yukon pyroCb that is discussed above. While region 2 is from fires in the Northwest Territories.

OMPS Aerosol Index image on 26 June (click to enlarge)

OMPS Aerosol Index image on 26 June (click to enlarge)

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