PyroCb in California

On 10 September a pyroCb formed from the Butte fire in California (38.4 N, 120.7 W). From the CAL FIRE website, this fire started on 09 September and as of 11 September the fire has burned about 50,000 acres. GOES-15 detected the smoke plume and pyroCb cloud, as well as the fire hot spot. Starting at 21:00 UTC on 10 September, 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 channel (left) and 3.9 µm shortwave IR channel images (right) (click to play animation)

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

In addition, using GOES-15 10.7 μm IR channel the cloud-top IR brightness temperature could be found. The animation below, starting at 22:30 UTC on 10 September, shows the brightness temperature for the pyroCb is -46.8ºC around 01:00 UTC on 11 September (green color enhancement).

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

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

Also, HYSPLIT forward forecasting can show the estimated transport of the smoke at 8000, 9000, and 10000 m. The image starting at 00:00 UTC on 11 September shows that the smoke is expected to move eastward. Depending on how far the smoke gets in the atmosphere can determine which trajectory the smoke will follow.

HYSPLIT Forward Trajectory (click to enlarge)

HYSPLIT Forward Trajectory (click to enlarge)

OMPS AI index images (courtesy of Colin Seftor) shows the transport of smoke on 11 September and 12 September. on 11 September the max AI index of 6.9 at 36.95 N 120.09 W, which is just south of the spot of the pyroCb. From the HYSPLIT above the smoke from 11 September OMPS seems to be following the green trajectory at 10000 m.

OMPS Aerosol Index image on 11 September (click to enlarge)

OMPS Aerosol Index image on 11 September (click to enlarge)

On 12 September the max AI index of 6.5  at 40.98 N 118.31 W, which is northwest of the pyroCb. On 12 September the smoke seemed to follow the red or blue trajectory on the HYSPLIT image.

OMPS Aerosol Index image on 12 September (click to enlarge)

OMPS Aerosol Index image on 12 September (click to enlarge)

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