{"id":396,"date":"2026-06-02T15:35:03","date_gmt":"2026-06-02T20:35:03","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/?p=396"},"modified":"2026-06-02T15:37:12","modified_gmt":"2026-06-02T20:37:12","slug":"alabama-mcs","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/2026\/06\/02\/alabama-mcs\/","title":{"rendered":"Alabama MCS"},"content":{"rendered":"\n<p class=\"wp-block-paragraph\">A mesoscale convective system (MCS) traversed the state of Alabama producing at least 200 damaging wind reports.<\/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\/06\/image-1024x697.png\" alt=\"\" class=\"wp-image-398\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/image-1024x697.png 1024w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/image-300x204.png 300w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/image-768x523.png 768w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/image-1536x1046.png 1536w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/image.png 1630w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Here is the SPC outlook discussion for this region. Interestingly, the western threat (in MO\/AR) didn&#8217;t materialize nearly to the extent of the MCS in Alabama. The MCS was characterized by lots of CAPE (2500-3500 J\/kg), adequate effective shear (25-35 kt), and steep low-level lapse rates (~ 8 C\/km).<\/p>\n\n\n\n<pre class=\"wp-block-preformatted\" style=\"font-size:13px\"><br>...Mid-South into the Southeast...<br>   An MCS is currently progressing generally southeastward, with<br>   preceding outflow arcing from southeast MO through far northwest TN.<br>   Some brief intensification was noted along this outflow, although<br>   updraft strength continues to be somewhat transient. General<br>   expectation is for this pattern of brief intensification to continue<br>   for the next hour or two, before building instability along the<br>   western edge of the outflow results in updraft\/downdraft cycles<br>   strong enough to produce strong to severe gusts. However, given<br>   limited deep-layer shear, overall updraft organization will likely<br>   remain transient.<br><br>   Additional new development is anticipated farther west during the<br>   afternoon from south-central MO into northern AR (and perhaps<br>   western TN and northern MS). Dewpoints in the 70s amid afternoon<br>   high temperatures in the upper 80s\/low 90s will support very strong<br>   buoyancy, with MLCAPE values around 4000 J\/kg. This buoyancy will<br>   support robust updrafts, but weak shear will limit storm<br>   organization, contributing to an outflow-dominant, multicellular<br>   mode. Even with limited organization, the updraft\/downdraft cycles<br>   should be strong enough for widespread strong\/severe storms capable<br>   of damaging wind gusts and some isolated hail.<br><br>   The storms, whether with the ongoing cluster or newer development<br>   farther west, may spread as far south as central MS\/AL during the<br>   evening before weakening.<\/pre>\n\n\n\n<p class=\"wp-block-paragraph\">The ProbSevere v4 model tracked this system quite well, with moderate to strong probabilities throughout, except for the very end in southeast Alabama. At this point, lightning activity was zero or very low, and it&#8217;s possible a strong gust front out ahead of the updrafts was causing the wind damage. NWS warnings also followed the convection well, as both NWS and PSv4 forecasts corresponded with next-45-minute reports. NWS did indeed capture the wind damage in southeast Alabama better than PSv4. We have noticed the PSv4 tends to excel at predicting organized convection but struggles often in low-lightning convection (though not always).<\/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\/06\/ps_AL_20260601.mp4\"><\/video><figcaption class=\"wp-element-caption\">ProbSevere v4 probabilities (contours), NWS severe thunderstorm warnings (orange polygons), SPC local storm reports in the 45 minutes <em>after<\/em> the image timestamp (circles), and MRMS MergedReflectivity (background).<\/figcaption><\/figure>\n\n\n\n<p class=\"wp-block-paragraph\">Here is a still image, where we can see the PSv4 predictions for the MCS as well as a southeast-moving storm on the South Carolina border. <\/p>\n\n\n\n<figure class=\"wp-block-image size-large\"><img loading=\"lazy\" decoding=\"async\" width=\"1024\" height=\"814\" src=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/iTerm2.jzb20V.PS_20260601-2000-1024x814.png\" alt=\"\" class=\"wp-image-402\" srcset=\"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/iTerm2.jzb20V.PS_20260601-2000-1024x814.png 1024w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/iTerm2.jzb20V.PS_20260601-2000-300x238.png 300w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/iTerm2.jzb20V.PS_20260601-2000-768x610.png 768w, https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-content\/uploads\/sites\/29\/2026\/06\/iTerm2.jzb20V.PS_20260601-2000.png 1062w\" sizes=\"auto, (max-width: 1024px) 100vw, 1024px\" \/><figcaption class=\"wp-element-caption\">ProbSevere v4 probabilities (contours), NWS severe thunderstorm warnings (orange polygons), SPC local storm reports in the 45 minutes <em>after<\/em> the image timestamp (circles), and MRMS MergedReflectivity (background).<\/figcaption><\/figure>\n","protected":false},"excerpt":{"rendered":"<p>A mesoscale convective system (MCS) traversed the state of Alabama producing at least 200 damaging wind reports. Here is the SPC outlook discussion for this region. Interestingly, the western threat (in MO\/AR) didn&#8217;t materialize nearly to the extent of the MCS in Alabama. The MCS was characterized by lots of CAPE (2500-3500 J\/kg), adequate effective [&hellip;]<\/p>\n","protected":false},"author":14,"featured_media":402,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[5],"tags":[6],"class_list":["post-396","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\/396","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=396"}],"version-history":[{"count":5,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts\/396\/revisions"}],"predecessor-version":[{"id":405,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/posts\/396\/revisions\/405"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/media\/402"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/media?parent=396"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/categories?post=396"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/probsevere\/wp-json\/wp\/v2\/tags?post=396"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}