![\"GOES-17](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2020\/05\/200523_goes17_goes16_shortwaveInfrared_nearInfrared_SFO_fire_anim.gif\")
<\/a>GOES-17 Shortwave Infrared (3.9 \u00b5m, top left),<\/em> GOES-16 Shortwave Infrared (3.9 \u00b5m, top right),<\/em> GOES-17 Near-Infrared “Snow\/Ice” (1.61 \u00b5m, bottom left)<\/em> and GOES-17 Near-Infrared “Cloud Particle Size” (2.24 \u00b5m,<\/em> bottom right)<\/em> [click to enlarge]<\/p><\/div>The thermal signature of a large nighttime fire at Pier 45 in San Francisco (media report<\/strong><\/a>) was evident in Shortwave Infrared (3.9 \u00b5m<\/strong><\/a>) images from GOES-17 (GOES-West)<\/em> and GOES-16 (GOES-East)<\/em> — the warmest 3.9 \u00b5m brightness temperature sensed by GOES-17 was 27.8\u00baC (at 1151 UTC<\/strong><\/a>), while the warmest temperature sensed by GOES-16 was only 14.2\u00baC (at 1146 UTC<\/strong><\/a>).<\/p>\n Note that a faint thermal signature of the fire (pixels exhibiting dim shades of white)<\/em> was also apparent in GOES-17 Near-Infrared “Snow\/Ice” (1.61 \u00b5m<\/strong><\/a>) and GOES-17 Near-Infrared “Cloud Particle Size” (2.24 \u00b5m<\/strong><\/a>) images. This is because those\u00a0two ABI<\/strong><\/a> spectral bands are located close to the peak emitted radiance of very hot features such as volcanic eruptions or large fires (below)<\/strong><\/em>.<\/p>\n Plots of Spectral Response Functions for ABI Bands 5, 6 and 7 [click to enlarge]<\/p><\/div>\n Just after sunrise, the northward meandering of smoke could be seen in GOES-17 “Red” Visible (0.64 \u00b5m<\/strong><\/a>) images (below)<\/strong>.<\/p>\n GOES-17 “Red” Visible (0.64 \u00b5m)<\/em> images [click to enlarge]<\/p><\/div>However, a larger-scale view of GOES-17 True Color Red-Green-Blue (RGB) images created using Geo2Grid<\/strong><\/a> (below)<\/strong><\/em> revealed that filaments of higher-altitude smoke were drifting southward, while the aforementioned low-latitude smoke was drifting more slowly northward.<\/p>\n<\/a><\/a>