{"id":5248,"date":"2026-06-27T13:33:04","date_gmt":"2026-06-27T13:33:04","guid":{"rendered":"https:\/\/ialert.com\/blog\/?p=5248"},"modified":"2026-06-27T13:33:04","modified_gmt":"2026-06-27T13:33:04","slug":"montana-severe-thunderstorms-june-27","status":"publish","type":"post","link":"https:\/\/ialert.com\/blog\/news-events\/montana-severe-thunderstorms-june-27\/","title":{"rendered":"Montana Severe Thunderstorms: Enhanced Risk of Giant Hail and 80+ mph Winds June 27"},"content":{"rendered":"<p> <iframe src=\"https:\/\/ialert.com\/blog_outlook.php?event=montana-severe-thunderstorms-enhanced-risk-june-27\" title=\"Montana Severe Thunderstorms: Enhanced \n  Risk of Giant Hail and 80+ mph Winds June 27\" loading=\"lazy\" style=\"width:100%;border:0;\" height=\"660\"><\/iframe><\/p>\n<p>Montana severe thunderstorms are threatening the northern High Plains on June 27, 2026, with the NOAA Storm Prediction Center issuing an Enhanced<br \/>\n  Risk, the third of five severe categories (level 3 of 5), centered on eastern Montana and western North Dakota. SPC uses a five-tier system to<br \/>\n  communicate severe weather potential; see the <a href=\"https:\/\/ialert.com\/blog\/weather-articles\/severe-weather-outlook\/\">SPC outlook risk categories<br \/>\n  explained<\/a> for a full breakdown. Storms are expected to fire late this afternoon and continue into early tonight, bringing very large hail up to 2 to<br \/>\n  3 inches in diameter, potentially destructive outflow winds exceeding 80 mph, and a limited tornado threat along the Montana and North Dakota border<br \/>\n  region.<\/p>\n<p><strong>Key points:<\/strong><\/p>\n<ul>\n<li>Enhanced Risk (level 3 of 5) covers eastern Montana and western North Dakota.<\/li>\n<li>Hail up to 2 to 3 inches in diameter possible near the MT\/ND border.<\/li>\n<li>MCS outflow winds of 80+ mph possible late evening into early tonight.<\/li>\n<li>Slight Risk (level 2 of 5) extends into western South Dakota, Nebraska, and North Carolina.<\/li>\n<li>SPC hazard probabilities: large hail 30%, damaging wind 30%, tornado 5%.<\/li>\n<\/ul>\n<h2>Where and When Montana Severe Thunderstorms Are Most Dangerous<\/h2>\n<p>Two main corridors will focus the Montana severe thunderstorms this afternoon: near the surface trough and lee cyclone close to the Montana and North<br \/>\n  Dakota border, and near the Big Horn Mountains in northern Wyoming. These initial storms carry the highest hail threat, with very large hail ranging from<br \/>\n  2 to 3 inches in diameter possible near the ND\/MT border. The SPC also notes a couple of tornadoes are possible with any supercells anchored along the<br \/>\n  surface boundary, though relatively large temperature-dewpoint spreads and uncertainty about storm mode could limit the tornado threat somewhat.<\/p>\n<p>By late evening and early tonight, storms are forecast to grow upscale and sweep northeastward across North Dakota as one or more mesoscale convective<br \/>\n  systems, or MCSs. Those MCS complexes could produce severe outflow winds topping 80 mph. Farther south, more isolated supercells into western South<br \/>\n  Dakota and Nebraska carry a Slight Risk, the second of five severe categories (level 2 of 5), with isolated very large hail and significant severe wind<br \/>\n  gusts also possible in that corridor. North Carolina is under a separate Slight Risk for isolated wind damage this afternoon.<\/p>\n<h2>What Is Driving These Storms Across the Northern High Plains<\/h2>\n<p>A closed mid-level low sitting over the northern Great Basin and northern Rockies is organizing the Montana severe thunderstorms. Embedded speed<br \/>\n  maxima, essentially pockets of faster-moving air within the upper-level flow, are rotating northeastward around the eastern edge of that low and<br \/>\n  providing the wind shear needed to sustain supercell thunderstorms. At the surface, a deep lee trough and cyclone along the central and northern High<br \/>\n  Plains is helping draw boundary-layer moisture northward from Kansas and Nebraska into the Dakotas, with dewpoints reaching into the 60s Fahrenheit.<\/p>\n<p>That moisture is streaming in beneath steep mid-level lapse rates, meaning the atmosphere cools very rapidly with height. Combined with daytime<br \/>\n  heating, this produces large Convective Available Potential Energy, or CAPE, which is the fuel that allows thunderstorms to grow tall, intense, and<br \/>\n  hail-producing. Early storms forming along the trough and near the Big Horn Mountains are likely to be discrete supercells, the storm mode most efficient<br \/>\n  at producing very large hail and tornadoes. As the evening progresses and the storm complex expands, storm mode is expected to shift toward MCS-type<br \/>\n  organization, which shifts the primary threat toward widespread, damaging straight-line winds.<\/p>\n<h2>Meteorologist&#8217;s Take<\/h2>\n<p>The setup for Montana severe thunderstorms today is textbook northern High Plains early summer. A closed upper-level low anchored over the northern<br \/>\n  Rockies is the key driver, spinning energy eastward and creating the wind shear profile supercells need to rotate. The steep lapse rates are the real<br \/>\n  wild card here: they are what allows hail to grow to baseball size or larger, and they are also what supercharges MCS outflow winds well into damaging<br \/>\n  territory once storms merge later tonight.<\/p>\n<p>The tornado risk is real but tempered. Larger temperature-dewpoint spreads in the boundary layer limit low-level moisture quality, and the anticipated<br \/>\n  transition from discrete supercells to a more linear or clustered storm mode reduces the window for sustained tornado-producing circulations. That said,<br \/>\n  the 5 percent tornado probability from the SPC is not trivial near the ND\/MT border this afternoon, especially before the storm mode transition occurs.<br \/>\n  The bigger story after sunset is likely the MCS wind threat pushing into North Dakota.<\/p>\n<h2>How to Stay Safe from Montana Severe Thunderstorms Today<\/h2>\n<p>If you are in eastern Montana, western North Dakota, western South Dakota, or Nebraska this afternoon and evening, the primary threats are very large<br \/>\n  hail and damaging winds. Hail at 2 to 3 inches in diameter can destroy vehicle glass, damage roofs, and injure anyone caught outdoors. Move vehicles<br \/>\n  under solid cover before storms arrive, and stay inside away from windows during any warning.<\/p>\n<p>A tornado watch or warning is possible near the MT\/ND border this afternoon. If a tornado warning is issued for your area, move immediately to an<br \/>\n  interior room on the lowest floor of a sturdy building. Keep a battery-powered or hand-crank weather radio nearby as power outages are possible with 80+<br \/>\n  mph outflow winds. Stay informed by checking <a href=\"https:\/\/ialert.com\/analysis.php#alerts\">active weather alerts<\/a> throughout the afternoon and<br \/>\n  evening, and set up push notifications through <a href=\"https:\/\/ialert.com\/\">iAlert weather alerts and notifications<\/a> so you are reached the moment a<br \/>\n  watch or warning is issued for your county.<\/p>\n<p>Montana severe thunderstorms and their downstream impacts across the Dakotas and Nebraska will evolve quickly tonight. Keep a close eye on updated SPC<br \/>\n  outlooks and local National Weather Service statements as storm initiation timing becomes clearer through the afternoon hours.<\/p>\n<p><strong>Sources:<\/strong><\/p>\n<ul>\n<li><a href=\"https:\/\/www.spc.noaa.gov\/products\/outlook\/day1otlk.html\" target=\"_blank\" rel=\"noopener\">NOAA Storm Prediction Center, Day 1 Convective Outlook, June 27, 2026<\/a><\/li>\n<\/ul>\n<div style=\"background: #000000; padding: 20px 24px; margin: 20px 0; border-radius: 4px;\">\n<p style=\"color: #ffffff; font-size: 16px; font-weight: bold; margin: 0 0 6px 0;\">Get Severe Weather Alerts for Your Location<\/p>\n<p style=\"color: rgba(255,255,255,0.9); margin: 0 0 14px 0;\">When any NWS watch, warning, or advisory is issued for your area, iAlert sends you an immediate notification by email, text message, or phone call, 24 hours a day, 7 days a week.<\/p>\n<p><a href=\"https:\/\/ialert.com\/signup.php\" style=\"background: #C41226; color: #ffffff; padding: 10px 22px; text-decoration: none; border-radius: 3px; font-weight: bold; display: inline-block;\">Sign Up for Severe Weather Alerts &rarr;<\/a>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Montana severe thunderstorms carry an Enhanced Risk on June 27, 2026, with 2-3 inch hail, 80+ mph winds, and tornado potential across the northern High Plains.<span class=\"more\"> <a href=\"https:\/\/ialert.com\/blog\/news-events\/montana-severe-thunderstorms-june-27\/\">Read More&#8230;<\/a><\/span><\/p>\n","protected":false},"author":6,"featured_media":5250,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":"","rank_math_focus_keyword":"Montana severe thunderstorms","rank_math_title":"Montana Severe Thunderstorms: 2-3\" Hail & 80 mph Winds","rank_math_description":"Montana severe thunderstorms carry an Enhanced Risk on June 27, 2026, with 2-3 inch hail, 80+ mph winds, and tornado potential across the northern High Plains."},"categories":[719],"tags":[776,772],"class_list":["post-5248","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news-events","tag-montana","tag-spc-outlook"],"acf":[],"_links":{"self":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5248","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/users\/6"}],"replies":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/comments?post=5248"}],"version-history":[{"count":4,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5248\/revisions"}],"predecessor-version":[{"id":5253,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5248\/revisions\/5253"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media\/5250"}],"wp:attachment":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media?parent=5248"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/categories?post=5248"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/tags?post=5248"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}