Wildfires in the northwestern US
McIDAS images of GOES-13 0.63 Âµm visible channel data during the day and 3.9 Âµm shortwave IR data at night (above; click image to play animation) revealed a number of very large and dense smoke plumes from wildfires that were burning in parts of the northwestern US (primarily in Idaho) on 28 August – 29 August 2012. The GOES-13 satellite had been placed into Rapid Scan Operations (RSO) mode, providing images as frequently as very 5-10 minutes.
During the following overnight hours, AWIPS images of Suomi NPP VIIRS 0.8 Âµm Day/Night Band (DNB), 3.74 Âµm shortwave IR, and 11.45 Âµm IR data (below) demonstrated the value of the DNB providing a visible channel at night (under ideal conditions of illumination by ample moonlight). While the 11.45 Âµm IR image verified that there were some patches of meteorological cloud in the region, the majority of the bright features seen on the DNB image were thick airborne smoke.
An even closer view using McIDAS-V images of VIIRS 0.8 Âµm DNB and 4.05 Âµm shortwave IR data (below; images courtesy of William Straka, CIMSS) highlighted the Mustang Fire Complex smoke plume and “fire hot spots” (black to yellow to red color enhancement) at 08:32 UTC. This fire was particularly hot, producing pyrocumulus clouds even into the night-time hours. The hottest IR brightness temperatureÂ in the red-enhanced region was 546.5 K (orÂ 273.4 C,Â 524 F).
===== 31 August Update =====
A night-time image comparison of the VIIRS 0.8 Âµm Day/Night Band and the corresponding 3.74 Âµm shortwave IR (below) revealed areas of smoke that were trapped in some of the valleys of central Idaho at 09:34 UTC (3:34 AM local time) on 31 August 2012.