{"id":23817,"date":"2017-04-27T21:59:44","date_gmt":"2017-04-27T21:59:44","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=23817"},"modified":"2017-05-01T14:13:22","modified_gmt":"2017-05-01T14:13:22","slug":"undular-bores-over-the-gulf-of-maine","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/23817","title":{"rendered":"Undular bores over the Gulf of Maine"},"content":{"rendered":"<p><em>** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. **<\/em><\/p>\n<p>As pointed out by <a href=\"http:\/\/www.weather.gov\/car\/\"><strong>NWS Caribou<\/strong><\/a>:<\/p>\n<p><center><\/p>\n<blockquote class=\"twitter-tweet\" data-lang=\"en\">\n<p dir=\"ltr\" lang=\"en\">Beautiful gravity waves over Gulf of Maine today, at several different levels too! <a href=\"https:\/\/twitter.com\/hashtag\/GOES16?src=hash\">#GOES16<\/a> data is preliminary, non-operational. <a href=\"https:\/\/twitter.com\/hashtag\/mewx?src=hash\">#mewx<\/a> <a href=\"https:\/\/t.co\/jbQEbAnPzz\">pic.twitter.com\/jbQEbAnPzz<\/a><\/p>\n<p>\u2014 NWS Caribou (@NWSCaribou) <a href=\"https:\/\/twitter.com\/NWSCaribou\/status\/857640324990107649\">April 27, 2017<\/a><\/p><\/blockquote>\n<p><script async src=\"\/\/platform.twitter.com\/widgets.js\" charset=\"utf-8\"><\/script><br \/>\n<\/center><br \/>\nnumerous packets of wave clouds associated with <strong><a href=\"https:\/\/en.wikipedia.org\/wiki\/Undular_bore\">undular bores<\/a><\/strong> were seen on GOES-16 Visible (<a href=\"http:\/\/www.goes-r.gov\/education\/docs\/ABI-bands-FS\/ABI%20Fact%20Sheet%20Band%202.pdf\"><strong>0.64 \u00b5m<\/strong><\/a>) imagery over the Gulf of Maine on the morning of <a href=\"http:\/\/www.wpc.ncep.noaa.gov\/dailywxmap\/index_20170427.html\"><strong>27 April 2017<\/strong><\/a>. A longer animation with surface wind plots<em><strong> (below;<\/strong> also available as an<strong> <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170427_goes16_goes13_visible_surface_winds_ME_MA_undular_bores_anim.mp4\">MP4 animation<\/a>)<\/strong><\/em> revealed the presence of 3 distinct bore structures: the largest and most well-defined which was moving eastward; a second (and much smaller) off the coast of Cape Cod which was moving southeastward; and a third which as moving <em>northwestward<\/em>\u00a0 (and eventually intersected the northern end of the primary eastward-moving bore).<\/p>\n<p><div style=\"width: 650px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170427_goes16_visible_surface_winds_ME_MA_undular_bores_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/960x1280_AGOES16_B2_G16_VIS_ME_MA_BORES_27APR2017_2017117_155720_0001PANEL.GIF\" alt=\"GOES-16 Visible (0.64 \u00b5m) images, with surface winds (knots) plotted in cyan [click to play animation]\" width=\"640\" height=\"480\" \/><\/a><p class=\"wp-caption-text\">GOES-16 Visible (0.64 \u00b5m) images, with surface winds (knots) plotted in cyan [click to play animation]<\/p><\/div>A comparison of GOES-16 and GOES-13 <em>(GOES-East)<\/em> Visible images<em><strong> (below; <\/strong>also available as an<strong> <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170427_goes16_goes13_visible_surface_winds_ME_MA_undular_bores_anim.mp4\">MP4 animation<\/a>)<\/strong><\/em> showed that undular bore wave cloud structures were more clearly clearly seen with the higher spatial spatial resolution of GOES-16 (0.5 km at satellite sub-point, vs 1.0 km for GOES-13). The comparison also showed that the visible imagery from GOES-13 (launched in May 2006, and operational as GOES-East since April 2010) was not as bright as that from GOES-16; this is due to the fact that the performance of GOES visible detectors tends to degrade over time.  <\/p>\n<p><div style=\"width: 650px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170427_goes16_goes13_visible_surface_winds_ME_MA_undular_bores_anim.gif\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/G16_G13_VIS_WINDB_ME_27APR2017_958x638_B21_2017117_143220_0002PANELS.GIF\" alt=\"GOES-16 Visible (0.64 \u00b5m, left) and GOES-13 Visible (0.63 \u00b5m, right) images [click to play animation] \" width=\"640\" height=\"480\" \/><\/a><p class=\"wp-caption-text\">GOES-16 Visible (0.64 \u00b5m, left) and GOES-13 Visible (0.63 \u00b5m, right) images [click to play animation]<\/p><\/div>So what caused these undular bores to form and propagate across the Gulf of Maine? Such gravity waves are ducted within strong temperature inversions &#8212; and <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170427_12UTC_CHATHAM_YARMOUTH.GIF\"><strong>rawinsonde data<\/strong><\/a> from Chatham, Massachusetts and Yarmouth, Nova Scotia indicated that such inversions were in place above the surface that morning. The northwestward-moving bore could have been initiated by surface outflow from thunderstorms associated with a mid-latitude cyclone (which was producing storm force and gale force winds: <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170426-27_west_atlantic_surface_analyses_anim.gif\"><strong>surface analyses<\/strong><\/a>) &#8212; GOES-16 Infrared Window (<a href=\"http:\/\/www.goes-r.gov\/education\/docs\/ABI-bands-FS\/ABI_Band_13_FS_CLEAN_LW_IR_FINAL.pdf\"><strong>10.3 \u00b5m<\/strong><\/a>) images<em><strong> (below; <\/strong>also available as an 88 Mbyte<strong> <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170426-27_goes16_infrared_anim.gif\">animated GIF<\/a>)<\/strong><\/em> showed these thunderstorms which developed within the warm sector of the coastal low pressure system. However, the forcing mechanism(s) that generated the eastward and southeastward moving bores remains somewhat of a mystery.<\/p>\n<div style=\"width: 650px\" class=\"wp-caption aligncenter\"><a class=\"thumbnail\" href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/170426-27_goes16_infrared_anim.mp4\"><img loading=\"lazy\" decoding=\"async\" class=\"thumbnail\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-content\/uploads\/sites\/5\/2017\/04\/960x1280_AGOES16_B13_G16_IR_ME_MA_BORES_26-27APR2017_2017116_120720_0001PANEL.GIF\" alt=\"GOES-16 Infrared Window (10.3 \u00b5m) images [click to play MP4 animation]\" width=\"640\" height=\"480\" \/><\/a><p class=\"wp-caption-text\">GOES-16 Infrared Window (10.3 \u00b5m) images [click to play MP4 animation]<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<p>** The GOES-16 data posted on this page are preliminary, non-operational data and are undergoing testing. ** As pointed out by NWS Caribou: Beautiful gravity waves over Gulf of Maine today, at several different levels too! #GOES16 data is preliminary, non-operational. #mewx pic.twitter.com\/jbQEbAnPzz \u2014 NWS Caribou (@NWSCaribou) April 27, 2017 numerous packets of wave clouds [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":23848,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[11,74],"tags":[],"class_list":["post-23817","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-goes-13","category-goes-16"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/23817","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=23817"}],"version-history":[{"count":16,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/23817\/revisions"}],"predecessor-version":[{"id":23833,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/23817\/revisions\/23833"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/23848"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=23817"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=23817"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=23817"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}