{"id":1650,"date":"2008-12-31T07:17:24","date_gmt":"2008-12-31T07:17:24","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=1650"},"modified":"2009-01-14T13:17:50","modified_gmt":"2009-01-14T13:17:50","slug":"cold-air-builds-in-alaska","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/1650","title":{"rendered":"Cold air builds in Alaska"},"content":{"rendered":"<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2008\/12\/081230_g11_ir_anim.gif\"><img loading=\"lazy\" decoding=\"async\" title=\"GOES-11 10.7 \u00c2\u00b5m IR images\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2008\/12\/081230_g11_ir_anim.gif\" alt=\"GOES-11 10.7 \u00c2\u00b5m IR images\" width=\"480\" height=\"360\" \/><\/a><p class=\"wp-caption-text\">GOES-11 10.7 \u00c2\u00b5m IR images<\/p><\/div>\n<p>Very cold air was becoming established across the interior of Alaska during the last few days of December 2008. AWIPS images of the 4-km resolution GOES-11 10.7 \u00c2\u00b5m IR channel <strong><em>(above)<\/em><\/strong> showed large areas exhibiting very cold IR brightness temperatures <em>(colder than -40\u00c2\u00ba C, darker blue color enhancement)<\/em> which were increasing in areal coverage as the surface temperatures continued to drop. The coldest air temperature measured in Alaska on <a title=\"30 December 2008 daily weather map\" href=\"http:\/\/www.hpc.ncep.noaa.gov\/dailywxmap\/index_20081230.html\" target=\"_blank\"><strong>30 December 2008<\/strong><\/a> was <strong>-49\u00c2\u00ba C (-57\u00c2\u00ba F)<\/strong> at O&#8217;Brien Creek; the temperature at the Fairbanks airport dropped to <strong>-41\u00c2\u00ba C (41\u00c2\u00ba F)<\/strong>, with the coldest location in the Fairbanks urban corridor <em>(the Woodsmoke subdivision at North Pole)<\/em> reaching  <strong>-43\u00c2\u00ba C (-46\u00c2\u00ba F)<\/strong>.<\/p>\n<p>A closer look using 1-km resolution 10.8 \u00c2\u00b5m IR data from the AVHRR instrument on the NOAA series of polar-orbiting satellites <strong><em>(below)<\/em><\/strong> showed remarkable detail in the cold surface temperatures, whose patterns were strongly influenced by elevation. Due to cold air drainage, the coldest surface IR temperatures <em>(indicated by the darkest blue color enhancement)<\/em> were found in lower elevations such as river valleys and the Yukon Flats area of interior Alaska &#8212; note that the Yukon Flats region <em>(located in the lower right quadrant of the images)<\/em> exhibited a progressively darker blue enhancement on these 3 IR images as the surface temperatures plummeted during that time period. The coldest IR brightness temperature seen on the 15:57 UTC image was <strong>222\u00c2\u00ba K (-51\u00c2\u00ba C, or -60\u00c2\u00ba F)<\/strong> &#8212; and the air temperature at Fort Yukon was <strong>-46\u00c2\u00ba C (-51\u00c2\u00ba F)<\/strong> at that particular time.<\/p>\n<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2008\/12\/081230_avhrr_ir_anim.gif\"><img loading=\"lazy\" decoding=\"async\" title=\"NOAA-15 \/ NOAA-17 \/ NOAA-18 AVHRR 10.8 \u00c2\u00b5m IR images\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2008\/12\/081230_avhrr_ir_anim.gif\" alt=\"NOAA-15 \/ NOAA-17 \/ NOAA-18 AVHRR 10.8 \u00c2\u00b5m IR images\" width=\"480\" height=\"360\" \/><\/a><p class=\"wp-caption-text\">NOAA-15 \/ NOAA-17 \/ NOAA-18 AVHRR 10.8 \u00c2\u00b5m IR images<\/p><\/div>\n<p>With such cold temperatures becoming established up in Alaska, parts of the Lower 48 states should be on notice for a possible arctic outbreak in the coming weeks&#8230;<\/p>\n<p><em><strong>&#8212; 04 JANUARY 2009 UPDATE &#8212;<\/strong><\/em><\/p>\n<p>The coldest temperatures during this particular streak of cold temperatures occurred on <a title=\"04 January 2009 daily weather map\" href=\"http:\/\/www.hpc.ncep.noaa.gov\/dailywxmap\/index_20090104.html\" target=\"_blank\"><strong>04 January 2009<\/strong><\/a>, when <strong>-54\u00c2\u00ba C (-65\u00c2\u00ba F)<\/strong> was reported at O&#8217;Brien Creek. A NOAA-17 AVHRR 10.8 \u00c2\u00b5m IR image <em><strong>(below)<\/strong><\/em> indicated that IR brightness temperatures in the Yukon Flats region <em>(located in the southeastern portion of the image)<\/em> were as cold as <strong>-52\u00c2\u00ba C (-62\u00c2\u00ba F)<\/strong> at 20:51 UTC <em>(11:51 AM local time)<\/em>.<\/p>\n<div style=\"width: 489px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/01\/090104_N17_IR4.GIF\" target=\"_blank\"><img loading=\"lazy\" decoding=\"async\" title=\"NOAA-17 AVHRR 10.8 \u00c2\u00b5m IR image\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2009\/01\/090104_N17_IR4.GIF\" alt=\"NOAA-17 AVHRR 10.8 \u00c2\u00b5m IR image\" width=\"479\" height=\"369\" \/><\/a><p class=\"wp-caption-text\">NOAA-17 AVHRR 10.8 \u00c2\u00b5m IR image<\/p><\/div>\n<p><strong><em>&#8212; 10 January 2009 Update &#8212;<\/em><\/strong><\/p>\n<p>The coldest official temperatures recorded in Alaska during this 15-day-long cold spell were <strong>-56\u00c2\u00ba C (-68\u00c2\u00ba F)<\/strong> at O&#8217;Brien Creek <em>(on 10 January)<\/em> and at Chicken <em>(on 08 January)<\/em>. In Fairbanks, the temperature remained below -40\u00c2\u00ba C\/F for a 24-hour period on 05-06 January.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Very cold air was becoming established across the interior of Alaska during the last few days of December 2008. AWIPS images of the 4-km resolution GOES-11 10.7 \u00c2\u00b5m IR channel (above) showed large areas exhibiting very cold IR brightness temperatures (colder than -40\u00c2\u00ba C, darker blue color enhancement) which were increasing in areal coverage as [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[37,22,18,5],"tags":[],"class_list":["post-1650","post","type-post","status-publish","format-standard","hentry","category-arctic","category-avhrr","category-goes-11","category-winter-weather"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/1650","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/users\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=1650"}],"version-history":[{"count":23,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/1650\/revisions"}],"predecessor-version":[{"id":1801,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/1650\/revisions\/1801"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=1650"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=1650"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=1650"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}