{"id":28604,"date":"2018-06-21T21:50:28","date_gmt":"2018-06-21T21:50:28","guid":{"rendered":"http:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=28604"},"modified":"2019-08-12T15:04:30","modified_gmt":"2019-08-12T15:04:30","slug":"summer-solstice-trowal-over-the-upper-midwest","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/28604","title":{"rendered":"Summer solstice TROWAL over the Upper Midwest"},"content":{"rendered":"

\"Aqua<\/a>

Aqua MODIS Water Vapor (6.7 \u00b5m)<\/em> image, with overlays of surface pressure\/fronts (cyan),<\/em> RUC model 310K equivalent potential temperature (red)<\/em> and 24-hour precipitation (green)<\/em> [click to enlarge]<\/p><\/div>A nighttime Aqua MODIS Water Vapor (6.7 \u00b5m) image (above)<\/strong><\/em> showed the well-defined circulation of a midlatitude cyclone that was centered over northwest Iowa at 0814 UTC (3:14 am local time) on 21 June 2018<\/strong><\/a>. Contours of RUC model equivalent potential temperature along the 310 K isentropic surface indicated that a Trough of Warm Air Aloft (TROWAL<\/strong><\/a>) existed just to the north of the occluded surface frontal boundary, curving cyclonically from northeastern Iowa across southern Minnesota into southeastern South Dakota, then southward across eastern Nebraska. 24-hour precipitation totals in excess of 2-3 inches had already been observed at that time.<\/p>\n

Suomi NPP VIIRS Infrared Window (11.45 \u00b5m) images (below)<\/strong><\/em> displayed minimum cloud-top brightness temperature values of -50 to -55\u00baC (yellow to orange enhancement)<\/em> near the TROWAL axis.<\/p>\n

\"Suomi<\/a>

Suomi NPP VIIRS Infrared Window (11.45 \u00b5m)<\/em> images, with plots of surface reports [click to enlarge]<\/p><\/div>An animation of GOES-16 (GOES-East)<\/em> Mid-level Water Vapor (6.9 \u00b5m<\/strong><\/a>) images (below)<\/strong><\/em> revealed that the storm system moved very slowly during the 00-20 UTC time period, while moderate to occasionally heavy rainfall was observed beneath the TROWAL air stream. 24-hour precipitation amounts reached 4-6 inches by 12 UTC<\/strong><\/a> in parts of southwest Minnesota, northwest Iowa and southeast South Dakota (FSD PNS<\/strong><\/a>) — and a number of river gauges were reporting minor to major flooding<\/strong><\/a> by the afternoon hours. This system was part of a prolonged flooding event (FSD summary<\/strong><\/a>).<\/p>\n

\"GOES-16<\/a>

GOES-16 Mid-level Water Vapor (6.9 \u00b5m)<\/em> images, with hourly plots of surface weather type [click to play MP4 animation]<\/p><\/div>It should be noted that TROWAL formation is rather unusual over this region during the summer months — but during the cold season a TROWAL can help to produce heavy snowfall (some examples are documented here<\/strong><\/a>, here<\/strong><\/a> and here<\/strong><\/a>).<\/p>\n","protected":false},"excerpt":{"rendered":"

A nighttime Aqua MODIS Water Vapor (6.7 \u00b5m) image (above) showed the well-defined circulation of a midlatitude cyclone that was centered over northwest Iowa at 0814 UTC (3:14 am local time) on 21 June 2018. Contours of RUC model equivalent potential temperature along the 310 K isentropic surface indicated that a Trough of Warm Air […]<\/p>\n","protected":false},"author":18,"featured_media":28606,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[70,74,16,12,49,48],"tags":[],"class_list":["post-28604","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-aqua","category-goes-16","category-heavy-rain-flooding","category-modis","category-suomi_npp","category-viirs"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/28604","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=28604"}],"version-history":[{"count":9,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/28604\/revisions"}],"predecessor-version":[{"id":33986,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/28604\/revisions\/33986"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/28606"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=28604"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=28604"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=28604"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}