{"id":26302,"date":"2017-12-10T23:59:22","date_gmt":"2017-12-10T23:59:22","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=26302"},"modified":"2017-12-13T02:50:20","modified_gmt":"2017-12-13T02:50:20","slug":"day-7-of-the-thomas-fire-in-southern-california","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/26302","title":{"rendered":"Day 7 of the Thomas Fire in Southern California"},"content":{"rendered":"

\"GOES-15<\/a>

GOES-15 Shortwave Infrared (3.9 \u00b5m) images, with hourly surface reports plotted in yellow [click to play MP4 animation]<\/p><\/div>The Thomas fire<\/strong><\/a> began burning in Southern California around 6:30 PM local time on 04 December (blog post<\/strong><\/a>) — and on 10 December 2017<\/strong><\/a>, GOES-15 (GOES-West)<\/em> Shortwave Infrared (3.9 \u00b5m) images (above)<\/strong><\/em> revealed that the fire showed little signs of diminishing during the nighttime hours, and in fact began to exhibit a trend of intensification around 05 UTC or 9 PM local time. However, toward the end of the day on 10 December, bands of\u00a0 thick cirrus clouds moving over the fire region acted to dramatically attenuate the satellite-detected thermal signature of the fire complex. Although the Santa Ana winds were not as intense as they had been during the previous week, some strong wind gusts<\/strong><\/a> were still observed.<\/p>\n

A sequence of 4 Shortwave Infrared images from Terra MODIS and Suomi NPP VIIRS (below)<\/strong><\/em> showed the westward and northwestward expansion of the fire during the 0637 to 2032 UTC period. The Thomas fire has now burned 230,000 acres, making it the fifth largest wildfire on record in California.<\/p>\n

\"Terra<\/a>

Terra MODIS and Suomi NPP VIIRS Shortwave Infrared images, with corresponding surface reports plotted in cyan [click to enlarge]<\/p><\/div>In a toggle between Terra MODIS true-color and false-color Red-Green-Blue (RGB) images at 1846 UTC (below; source<\/a>)<\/strong><\/em> the true-color image revealed a broad plume of thick smoke being transported westward and northwestward from the fire source region, while the false-color image showed the areal coverage of the burn scar (which appeared as reddish-brown hues beneath the clouds)<\/em> as well as locations of the larger and more intense active fires (brighter pink to white)<\/em> that were burning along the northern to western perimeter of the burn scar.<\/p>\n

\"Terra<\/a>

Terra MODIS true-color and false-color images [click to enlarge]<\/p><\/div>A comparison of Suomi NPP VIIRS Visible (0.64 \u00b5m), Shortwave Infrared (3.74 \u00b5m) and Infrared Window (11.45 \u00b5m) images at 2032 UTC or 12:32 PM\u00a0 local time (below)<\/strong><\/em> showed a well-defined thermal signature before the thicker cirrus clouds moved overhead from the south. A small cloud cluster (located just northwest of the fire thermal signature) exhibited a minimum infrared brightness temperature of -43\u00baC<\/a><\/strong> — if this cloud feature was indeed generated by the fire complex, it meets the -40\u00baC criteria of a pyrocumulonimbus cloud.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS Visible (0.64 \u00b5m), Shortwave Infrared (3.74 \u00b5m) and Infrared Window (11.45 \u00b5m) images, with surface reports plotted in cyan [click to enlarge]<\/p><\/div>The fire was producing very thick smoke, in addition to deep pyrocumulus clouds (top photo taken around 1945 UTC or 11:45 AM local time):<\/p>\n

<\/p>\n
\n

Massive imposing smoke from #ThomasFire<\/a> today. Looking west from Newbury Park. pic.twitter.com\/gekRcWcPiO<\/a><\/p>\n

\u2014 Greg Vit (@gvitty) December 10, 2017<\/a><\/p><\/blockquote>\n