{"id":19562,"date":"2015-09-20T23:59:02","date_gmt":"2015-09-20T23:59:02","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=19562"},"modified":"2015-09-23T18:57:44","modified_gmt":"2015-09-23T18:57:44","slug":"mountain-wave-clouds-in-western-montana","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/19562","title":{"rendered":"Mountain wave clouds in western Montana"},"content":{"rendered":"<p><center><\/p>\n<blockquote class=\"twitter-tweet\" lang=\"en\">\n<p dir=\"ltr\" lang=\"en\">The Chinook Arch (a stationary cloud formation downwind of the Rockies) should move E and diminsh this aftn. <a href=\"https:\/\/twitter.com\/hashtag\/mtwx?src=hash\">#mtwx<\/a> <a href=\"http:\/\/t.co\/UdfRRjOnBF\">pic.twitter.com\/UdfRRjOnBF<\/a><\/p>\n<p>\u2014 NWS Great Falls (@NWSGreatFalls) <a href=\"https:\/\/twitter.com\/NWSGreatFalls\/status\/645656807373824000\">September 20, 2015<\/a><\/p><\/blockquote>\n<p><script src=\"\/\/platform.twitter.com\/widgets.js\" async=\"\" charset=\"utf-8\"><\/script><br \/>\n<\/center><\/p>\n<p>As pointed out in a Tweet from <a href=\"http:\/\/www.wrh.noaa.gov\/tfx\/\"><strong>NWS Great Falls<\/strong><\/a> <em><strong>(above),<\/strong><\/em> a &#8220;chinook arch&#8221; mountain wave cloud feature had formed in response to strong westerly winds interacting with the high terrain of the Rocky Mountains of western Montana on <a href=\"http:\/\/www.wpc.ncep.noaa.gov\/dailywxmap\/index_20150620.html\"><strong>20 September 2015<\/strong><\/a>. GOES-13 visible (0.63 \u00b5m) images <em><strong>(below; also available as an <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_visible_Montana_mountain_waves_anim.mp4\">MP4 movie file<\/a>)<\/strong><\/em> showed the development and evolution of the lower-altitude parallel bands of mountain wave clouds, as well as the larger patch of higher-altitude cloud immediately downwind of the eastern edge of the highest terrain (comparison of <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_1918utc_suomi_npp_viirs_truecolor_map_anim.gif\"><strong>Suomi NPP VIIRS visible image and terrain<\/strong><\/a>) .<\/p>\n<p><div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_visible_Montana_mountain_waves_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/960x1280_AGOES13_B1_G13_VIS_MT_MNT_WAVE_1_2015263_211500.GIF\" alt=\"GOES-13 visible (0.63 \u00b5m) images [click to play animation]\" width=\"480\" height=\"360\" \/><\/a><p class=\"wp-caption-text\">GOES-13 visible (0.63 \u00b5m) images [click to play animation]<\/p><\/div>The corresponding GOES-13 infrared (10.7 \u00b5m) images <em><strong>(below; also available as an <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_infrared_Montana_mountain_waves_anim.mp4\">MP4 movie file<\/a>)<\/strong><\/em> revealed that the large patch of high-altitude cloud (sometimes referred to as a &#8220;banner cloud&#8221;) began to grow in areal coverage after about 12 UTC, eventually exhibiting cloud-top IR brightness temperatures in the -50 to -55\u00ba C range <em>(yellow to orange color enhancement).<\/em><\/p>\n<p><div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_infrared_Montana_mountain_waves_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/960x1280_AGOES13_B4_G13_IR_MT_MNT_WAVE_1_2015263_211500.GIF\" alt=\"GOES-13 infrared (10.7 um) images [click to play animation]\" width=\"480\" height=\"360\" \/><\/a><p class=\"wp-caption-text\">GOES-13 infrared (10.7 um) images [click to play animation]<\/p><\/div>The GOES-13 water vapor (6.5 \u00b5m) images <em><strong>(below; also available as an <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_water_vapor_Montana_mountain_waves_anim.mp4\">MP4 movie file<\/a>)<\/strong><\/em> did not show the common signature of a jet streak axis (a well-defined moist-to-dry gradient) until later in the day.<\/p>\n<p><div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_goes13_water_vapor_Montana_mountain_waves_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/960x1280_AGOES13_B3_G13_WV_MT_MNT_WAVE_1_2015263_211500.GIF\" alt=\"GOES-13 water vapor (6.5 um) images [click to play animation]\" width=\"480\" height=\"360\" \/><\/a><p class=\"wp-caption-text\">GOES-13 water vapor (6.5 um) images [click to play animation]<\/p><\/div>A comparison of Aqua MODIS visible (0.65 \u00b5m) and &#8220;cirrus detection&#8221; (1.375 \u00b5m) images at 1949 UTC<strong><em> (below)<\/em><\/strong> demonstrated how the cirrus channel imagery can be used to better discriminate between the high-altitude ice clouds (brighter white features) and the low-altitude water and\/or supercooled water droplet clouds.<\/p>\n<p><div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_1949utc_aqua_modis_visible_cirrs_MT_mountain_waves_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_1949utc_aqua_modis_visible_cirrs_MT_mountain_waves_anim.gif\" alt=\"Aqua MODIS visible (0.65 um) and \" width=\"480\" height=\"310\" \/><\/a><p class=\"wp-caption-text\">Aqua MODIS visible (0.65 um) and &#8220;cirrus detection&#8221; (1.375 um) images [click to enlarge]<\/p><\/div>A comparison of Suomi NPP VIIRS visible (0.64 \u00b5m), infrared window (11.45 \u00b5m) and shortwave infrared (3.74 \u00b5m) images at 2057 UTC <em><strong>(below)<\/strong><\/em> showed the high-altitude banner cloud feature as it was beginning to enter its dissipation phase. The 11.45 \u00b5m cloud-top IR brightness temperatures were as cold as -57\u00ba C; however, note that the 3.74 \u00b5m shortwave IR brightness temperatures were significantly warmer (in the +5 to +10\u00ba C range). These warm shortwave IR temperatures indicated that the banner cloud feature was composed of very small ice crystals, which were effective at reflecting incoming solar radiation back toward the satellite sensors.<\/p>\n<div style=\"width: 490px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_2057utc_suomi_npp_viirs_Visible_IR_shortwaveIR_MT_mountain_wave_clouds_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2015\/09\/150920_2057utc_suomi_npp_viirs_Visible_IR_shortwaveIR_MT_mountain_wave_clouds_anim.gif\" alt=\"Suomi NPP VIIRS visible (0.64 um), infrared window (11.45 um), and shortwave infrared (3.74 um) images [click to enlarge]\" width=\"480\" height=\"389\" \/><\/a><p class=\"wp-caption-text\">Suomi NPP VIIRS visible (0.64 um), infrared window (11.45 um), and shortwave infrared (3.74 um) images [click to enlarge]<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<p>The Chinook Arch (a stationary cloud formation downwind of the Rockies) should move E and diminsh this aftn. #mtwx pic.twitter.com\/UdfRRjOnBF \u2014 NWS Great Falls (@NWSGreatFalls) September 20, 2015 As pointed out in a Tweet from NWS Great Falls (above), a &#8220;chinook arch&#8221; mountain wave cloud feature had formed in response to strong westerly winds interacting [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":19576,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[21,11,12,49,48],"tags":[],"class_list":["post-19562","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aviation","category-goes-13","category-modis","category-suomi_npp","category-viirs"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/19562","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=19562"}],"version-history":[{"count":4,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/19562\/revisions"}],"predecessor-version":[{"id":19577,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/19562\/revisions\/19577"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/19576"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=19562"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=19562"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=19562"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}