![\"Suomi](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2018\/11\/181124_suomiNPP_viirs_dayNightBand_infraredWindow_AK_2_anim.gif\")
<\/a>Suomi NPP VIIRS Day\/Night Band (0.7 \u00b5m)<\/em> and Infrared Window (11.45 \u00b5m)<\/em> images [click to enlarge]<\/p><\/div>A sequence of Suomi\u00a0NPP VIIRS Day\/Night Band (0.7 \u00b5m) and Infrared Window (11.45 \u00b5m) images centered over the North Slope of Alaska (above)<\/strong><\/em> showed a few patches of thin stratus cloud drifting westward on 24 November 2018. Ample illumination from the Moon — which was in the Waning Gibbous phase, at 98% of Full — maximized the “visible image at night” capability of the Day\/Night Band. A faster animation of Infrared images<\/strong><\/a> helped to emphasize the westward motion of multi-year drift ice in the Beaufort Sea as it collided with the growing wedge of first-year land-fast ice off the northeast coast of Alaska.<\/p>\n In areas with deeper snow cover that remained generally cloud-free for long periods of time, temperatures at first-order stations dropped into the -20s and -30s F; a low of -35\u00baF<\/strong><\/a> was recorded at\u00a0Nuiqsut (PAQT). A closer look at the 2314 UTC Infrared image (below)<\/strong><\/em> revealed surface brightness temperatures as cold as -47\u00baC or -53\u00baF (lighter shades of yellow)<\/em> in the valleys near Galbraith Lake (PAGB).<\/p>\n Suomi NPP VIIRS Infrared Window (11.45 \u00b5m) image at 2314 UTC [click to enlarge]<\/p><\/div>The RAWS site at Umiat Airfield (PAUM) registered a minimum temperature of -40\u00baF (hourly summary<\/strong><\/a>) at 2123 UTC on 24 November (below)<\/strong><\/em> — this was the first reliable -40\u00ba temperature of the 2018\/2019 Winter season in Alaska. Farther to the east, the HADS site at Sagavanirktok recorded a low of -44F<\/strong><\/a>, but that max\/min temperature data<\/strong><\/a> was flagged as being suspect (red)<\/em> by Mesowest<\/strong><\/a> quality control.<\/p>\n<\/a>