{"id":355,"date":"2026-05-21T14:29:02","date_gmt":"2026-05-21T19:29:02","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/?p=355"},"modified":"2026-05-21T14:29:02","modified_gmt":"2026-05-21T19:29:02","slug":"regional-severe-weather-outbreaks","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/2026\/05\/21\/regional-severe-weather-outbreaks\/","title":{"rendered":"Regional Severe Weather Outbreaks"},"content":{"rendered":"\n<p>Two areas of focus came into view for severe weather this day. One in the Midwest, and one on the Great Plains. You can see both in the SPC&#8217;s outlook and verification graphic.<\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"697\" src=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5-1024x697.png\" alt=\"\" class=\"wp-image-359\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5-1024x697.png 1024w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5-300x204.png 300w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5-768x523.png 768w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5-1536x1046.png 1536w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/image-5.png 1630w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">SPC categorical outlook with verification for 2026-05-18.<\/figcaption><\/figure>\n\n\n\n<p>In the Midwest, a mesoscale convective system from the previous night was traversing the middle of the country, reloading with instability ahead of it. You can see numerous wind reports in the animation below (reports are plotted in the previous 40 minutes). A 79-mph microburst was recorded at Midway International Airport. The ProbSevere v4 model captured this high-end event and other damaging wind reports much better than PSv3. The probabilities really picked up as convection entered Michigan, with widespread wind damage and severe gusts reported in areas of > 50% probability. There was a strong false alarm area for about an hour in northern Michigan, where NWS severe thunderstorm warnings were also present.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"720\" style=\"aspect-ratio: 1280 \/ 720;\" width=\"1280\" controls src=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/ps_20260518.mp4\"><\/video><figcaption class=\"wp-element-caption\">ProbSevere v4 (contours), NWS severe weather warnings (orange and red boxes), SPC storm reports in the previous 40 minutes, and MRMS MergedReflectivity.<\/figcaption><\/figure>\n\n\n\n<p>On the Plains, tornadic supercells stole the show. The SPC issued a PDS tornado watch for parts of Nebraska and Kansas, which is fairly rare. Despite the complicated scene, the PSv4 model tracked most storms well. However, hailers behind the main line of supercells and then the portion of the squall line that hit Kansas City, MO (producing many wind reports) were underestimated. Both areas warrant further investigation.<\/p>\n\n\n\n<figure class=\"wp-block-video\"><video height=\"720\" style=\"aspect-ratio: 1280 \/ 720;\" width=\"1280\" controls src=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/05\/ps_20260518-19.mp4\"><\/video><figcaption class=\"wp-element-caption\">ProbSevere v4 (contours), NWS severe weather warnings (orange and red boxes), SPC storm reports in the previous 40 minutes, and MRMS MergedReflectivity.<\/figcaption><\/figure>\n\n\n\n<p><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Two areas of focus came into view for severe weather this day. One in the Midwest, and one on the Great Plains. You can see both in the SPC&#8217;s outlook and verification graphic. In the Midwest, a mesoscale convective system from the previous night was traversing the middle of the country, reloading with instability ahead [&hellip;]<\/p>\n","protected":false},"author":14,"featured_media":359,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[5],"tags":[6],"class_list":["post-355","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-psv4","tag-psv4"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts\/355","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/users\/14"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/comments?post=355"}],"version-history":[{"count":2,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts\/355\/revisions"}],"predecessor-version":[{"id":361,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts\/355\/revisions\/361"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/media\/359"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/media?parent=355"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/categories?post=355"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/tags?post=355"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}