Transport of Canadian wildfire smoke across the Northeast US

May 22nd, 2019 |

GOES-16 CIMSS Natural Color images, with an overlay of the Smoke Detection Product ;click to play animation | MP4]

GOES-16 CIMSS Natural Color RGB images, with an overlay of the Smoke Detection Product [click to play animation | MP4]

GOES-16 (GOES-East) CIMSS Natural Color Red-Green-Blue (RGB) images with an overlay of the Smoke Detection Product (above) revealed curved filaments of wildfire smoke moving southeastward across the Northeast US and the adjacent offshore waters of the Atlantic Ocean on 22 May 2019. The smoke filaments were classified as Medium/High confidence by the algorithm — additional information on GOES-R Aerosol Detection Products in AWIPS is available here and here.

During the preceding overnight hours, with ample illumination from the Moon (in the Waning Gibbous phase, at 92% of Full) smoke filaments were evident over the Atlantic Ocean on Suomi NPP VIIRS Day/Night Band (0.7 µm) imagery at 0722 UTC or 3:22 AM Eastern Time (below). Note that the smoke did not exhibit a signature in the corresponding VIIRS Infrared Window (11.45 µm) image, since thin smoke layers are effectively transparent to infrared radiation.

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0722 UTC [click to enlarge]

Suomi NPP VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0722 UTC [click to enlarge]

Daily composites of Suomi NPP VIIRS True Color RGB images with VIIRS Fire Detections viewed using RealEarth (below) showed that thick smoke from wildfires in northern Alberta — primarily the Chuckegg Creek Fire that forced evacuations in the town of High Level — was initially lofted above the meteorological clouds over the Northwest Territories and Nunavut on 19 May and 20 May, before eventually moving southeastward across central/eastern Canada.

Daily composites of Suomi NPP VIIRS True Color RGB images with Fire Detections, 18-22 May [click to play animation]

Daily composites of Suomi NPP VIIRS True Color RGB images with Fire Detections, 18-22 May [click to play animation]

HYSPLIT model 72-hour back trajectories from 3 points corresponding to the smoke filaments seen in the GOES-16 imagery off the Northeast US coast (below) confirmed an initial anticyclonic transport from the region of the Alberta wildfires, with a subsequent southeastward transport across Canada and eventually the Northeast US.

HYSPLIT model 72-hour back trajectories from 3 points off the Northeast US coast [click to enlarge]

HYSPLIT model 72-hour back trajectories from 3 points off the Northeast US coast

6-hourly GFS 500 hPa analyses (source) shown below help to explain the smoke transport as seen in both the VIIRS imagery and the HYSPLIT trajectories — a ridge of high pressure was present over western Canada early in the period, with a transition to a deepening longwave trough over eastern Canada with a shortwave trough digging across Quebec and the Maritimes on 21-22 May. Strong descent of the trajectories occurred during the final 12 hours of transport, on the back side of the digging shortwave trough.

6-hourly GFS 500 hPa analyses [click to enlarge]

6-hourly GFS 500 hPa analyses, from 12 UTC on 18 May to 12 UTC on 22 May [click to enlarge]

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