{"id":5479,"date":"2026-08-09T12:39:05","date_gmt":"2026-08-09T12:39:05","guid":{"rendered":"https:\/\/ialert.com\/blog\/?p=5479"},"modified":"2026-08-09T12:39:05","modified_gmt":"2026-08-09T12:39:05","slug":"midwest-severe-thunderstorms-aug-9","status":"publish","type":"post","link":"https:\/\/ialert.com\/blog\/news-events\/midwest-severe-thunderstorms-aug-9\/","title":{"rendered":"Midwest Severe Thunderstorms: Slight Risk of Damaging Winds From Eastern Iowa to Toledo, August 9, 2026"},"content":{"rendered":"<p> <iframe src=\"https:\/\/ialert.com\/blog_outlook.php?event=midwest-severe-thunderstorms-aug-9\" title=\"Midwest Severe Thunderstorms: Slight Risk of Damaging \n  Winds From Minnesota to Michigan, August 9, 2026\" loading=\"lazy\" style=\"width:100%;border:0;\" height=\"660\"><\/iframe><\/p>\n<p>Midwest severe thunderstorms are today&#8217;s main weather story, August 9, 2026, with the NOAA Storm Prediction Center drawing a Slight Risk across a<br \/>\n  corridor that runs from southeast Minnesota and eastern Iowa east through northern Illinois and northern Indiana to the Lake Michigan area. A Slight Risk<br \/>\n  is the second of five severe categories (level 2 of 5). Chicago, Milwaukee, Madison, and Rockford are inside it. Damaging wind is the primary hazard, with<br \/>\n  a 15% damaging wind probability across the corridor.<\/p>\n<p><strong>Key points:<\/strong><\/p>\n<ul>\n<li>A Slight Risk (level 2 of 5) for midwest severe thunderstorms covers Chicago, Milwaukee, Madison, Rockford, Peoria, Champaign, Davenport, Dubuque,<br \/>\n  Iowa City, Waterloo, Cedar Rapids, Rochester MN, Gary, South Bend, Fort Wayne, Kalamazoo, and Toledo.<\/li>\n<li>Damaging wind is the main hazard for midwest severe thunderstorms, at a 15% probability.<\/li>\n<li>A 2% tornado probability covers a narrower zone than the midwest severe thunderstorms wind area: eastern Iowa, northern Illinois, and northern<br \/>\n  Indiana, including Chicago, Davenport, Gary, and Fort Wayne. Milwaukee, Madison, Toledo, and Kalamazoo are outside it.<\/li>\n<li>Hail in the Midwest is a 5% probability, not 15%. The 15% large hail area is in the Dakotas only.<\/li>\n<li>A second Slight Risk covers the Dakotas, where large hail is the lead hazard. Pierre, Mitchell, Dickinson, and Williston are inside it.<\/li>\n<li>Minneapolis, St. Paul, Detroit, Grand Rapids, Lansing, Des Moines, and Indianapolis are all outside the Slight Risk.<\/li>\n<li>SPC says higher probabilities may be needed in later outlooks, depending on how the morning convection evolves.<\/li>\n<\/ul>\n<h2>Where Midwest Severe Thunderstorms Are Most Likely Today<\/h2>\n<p>There are two separate Slight Risk areas for midwest severe thunderstorms today, and they carry different lead hazards. The Midwest corridor is the<br \/>\n  wind story. It begins over southeast Minnesota near Rochester and eastern Iowa at Waterloo, Cedar Rapids, Dubuque, Iowa City, and Davenport, runs east<br \/>\n  across southern Wisconsin through Madison, Milwaukee, and Kenosha, covers northern Illinois including Rockford, Joliet, Chicago, Peoria, and Champaign,<br \/>\n  then continues through northern Indiana at Gary, South Bend, Lafayette, and Fort Wayne, clipping southwest Lower Michigan at Kalamazoo and ending right at<br \/>\n  Toledo.<\/p>\n<p>The boundary matters more than usual with today&#8217;s midwest severe thunderstorms, because several large metros people assume are included are not.<br \/>\n  <strong>Minneapolis and St. Paul are not in the Slight Risk.<\/strong> Neither is Detroit, Grand Rapids, Lansing, Ann Arbor, Flint, Saginaw, Des Moines,<br \/>\n  Indianapolis, Springfield, or Cleveland. Those sit in the surrounding Marginal Risk (level 1 of 5), where isolated severe storms are still possible. St.<br \/>\n  Louis, Kansas City, Columbus, Cincinnati, Duluth, Green Bay, and Eau Claire are in the General Thunderstorm area only.<\/p>\n<p>SPC uses a five-tier system to communicate severe weather potential, and you can explore <a \n  href=\"https:\/\/ialert.com\/blog\/weather-articles\/severe-weather-outlook\/\">how the SPC outlook risk categories work<\/a> for full detail. A Slight Risk for<br \/>\n  midwest severe thunderstorms means scattered severe storms are possible, not that a widespread outbreak is expected.<\/p>\n<p>Convection was already ongoing this morning across southern Minnesota into eastern Iowa. The SPC expects that activity to keep spreading east toward<br \/>\n  the Lake Michigan vicinity through the afternoon, riding the nose of a modest low-level jet along a surface front oriented across southern Wisconsin and<br \/>\n  Lower Michigan, and to intensify as it moves into a destabilizing air mass by midday. Additional development is possible in the moisture-rich warm sector<br \/>\n  across northern Illinois and Indiana, along the southern flank of that ongoing convection and its outflow. That is the second seeding mechanism for<br \/>\n  today&#8217;s midwest severe thunderstorms.<\/p>\n<div style=\"background:#000000; padding:22px 24px; margin:24px 0; border-radius:4px;\">\n<p style=\"color:#ffffff; font-size:18px; font-weight:bold; margin:0 0 6px 0;\">Get iAlert Notifications for Your Location<\/p>\n<p style=\"color:rgba(255,255,255,0.9); margin:0 0 16px 0;\">The moment a threat is issued for your area, iAlert sends an immediate alert by email, text message, or phone call, 24\/7. Choose the alerts you need:<\/p>\n<p><a href=\"https:\/\/ialert.com\/services\/severe-weather-alerts.php\" style=\"background:#C41226; color:#ffffff; padding:11px 22px; text-decoration:none; border-radius:3px; font-weight:bold; display:inline-block; margin:0 12px 8px 0;\">Severe Weather Alerts &rarr;<\/a><br \/>\n<a href=\"https:\/\/ialert.com\/services\/lightning_detection_alerts.php\" style=\"background:#C41226; color:#ffffff; padding:11px 22px; text-decoration:none; border-radius:3px; font-weight:bold; display:inline-block; margin:0 0 8px 0;\">&#9889; Lightning Detection Alerts &rarr;<\/a>\n<\/div>\n<h2>The Dakotas Slight Risk Is a Hail Story<\/h2>\n<p>The second Slight Risk covers the Dakotas, and it is where the highest hail probabilities are. Pierre and Mitchell in South Dakota and Dickinson and<br \/>\n  Williston in North Dakota are inside it. This is the only part of the country today carrying a <strong>15% large hail probability<\/strong>. Rapid City,<br \/>\n  Aberdeen, Watertown, Sioux Falls, and Bismarck are just outside in the Marginal Risk.<\/p>\n<p>One point the outlook makes that the map alone does not: western Nebraska is in the Marginal Risk, not the Slight. Chadron, Alliance, and Valentine<br \/>\n  carry a 5% hail probability with no wind probability drawn. Scottsbluff, North Platte, Grand Island, Lincoln, and Omaha are in the General Thunderstorm<br \/>\n  area.<\/p>\n<p>The SPC also outlines conditional intensity areas in the Dakotas, the hatched zones on the probability maps. A hail intensity area covers western South<br \/>\n  Dakota and southwest North Dakota near Dickinson, and a wind intensity area covers central South Dakota near Pierre and Mitchell. Those mark where any<br \/>\n  storm that does form could reach the higher end of the hazard rather than merely meeting severe criteria.<\/p>\n<p>A surface front is expected to develop southward across the central Plains and become oriented across northern Kansas by tonight. Low-level warm<br \/>\n  advection above that boundary, with surface winds turning south to southeasterly, will hold dewpoints in the 60s across the region.<\/p>\n<figure class=\"wp-block-image size-full\" style=\"max-width:880px;margin:28px auto;padding:10px;border:1px solid\n  #dde3ec;border-radius:6px;background:#ffffff;\"><br \/>\n    <img decoding=\"async\" src=\"https:\/\/ialert.com\/blog\/wp-content\/uploads\/2026\/08\/ialert-midwest-severe-thunderstorms-wind-risk-august-9-2026.jpg\" alt=\"Midwest severe\n  thunderstorms damaging wind risk map for August 9, 2026, showing the SPC 15 percent wind probability over the Chicago area and the Dakotas\" width=\"1600\" \n  height=\"830\" style=\"max-width:100%;height:auto;border-radius:4px;\" loading=\"lazy\" \/><figcaption style=\"font-size:0.86em;color:#1a3a5c;text-align:center;margin:12px 6px 2px;line-height:1.45;\">SPC damaging wind probabilities for August 9,<br \/>\n  2026. The 15% area (yellow) covers the Midwest corridor from eastern Iowa through Chicago into northern Indiana, plus a second area over the Dakotas. The<br \/>\n  hatched Intensity Level 1 zone over central South Dakota marks where the highest-end gusts are conditionally possible. The 5% area (brown) extends the<br \/>\n  threat across the upper Midwest, the southern Appalachians, Maine, and Arizona. Source: NOAA Storm Prediction Center.<\/figcaption><\/figure>\n<h2>Meteorologist&#8217;s Take on Today&#8217;s Midwest Severe Thunderstorms<\/h2>\n<p>The organizing feature for today&#8217;s midwest severe thunderstorms is a surface front draped across southern Wisconsin and Lower Michigan. Morning<br \/>\n  convection over southern Minnesota and eastern Iowa is the seed. What determines whether this becomes a significant wind event is whether that activity<br \/>\n  survives its trip east into the better air mass.<\/p>\n<p>The ingredients downstream of today&#8217;s midwest severe thunderstorms are strong. The SPC forecasts strong to extreme instability along the corridor, and<br \/>\n  vertically veering wind profiles supporting effective shear over 30 knots. That combination sustains organized, long-lived storms rather than pulse cells,<br \/>\n  which is what turns scattered convection into a damaging wind swath.<\/p>\n<p>The tornado mention deserves precision. Low-level storm-relative helicity is enhanced right along the surface boundary, which is why a tornado or two<br \/>\n  cannot be excluded. But the 2% tornado probability is drawn over a much smaller area than the midwest severe thunderstorms wind risk: eastern Iowa,<br \/>\n  northern Illinois, and northern Indiana. Milwaukee, Madison, Rochester, Kalamazoo, and Toledo are all in the Slight Risk for wind while sitting outside<br \/>\n  the tornado area entirely. Wind is the headline everywhere; the tornado caveat applies to a specific slice.<\/p>\n<p>In the Dakotas the driver is different in kind. A post-frontal upslope regime with dewpoints in the 60s, moderate northwesterly flow aloft, and a<br \/>\n  developing south to southwesterly low-level jet produce supercell wind profiles. Add steep low-level lapse rates and initial storms are hail producers,<br \/>\n  which is why that area and not the Midwest carries the 15% hail probability.<\/p>\n<p>The escalation risk is in the Dakotas overnight. The SPC notes that if clusters and outflow can consolidate, upscale growth during the late evening<br \/>\n  into the overnight is possible, raising the threat for swaths of damaging gusts across the northern Plains. That is the path from a scattered hail event<br \/>\n  to an organized wind event, and it is worth watching after dark.<\/p>\n<p>Two smaller areas round out the day. Over the southern Appalachians, scattered storms over higher terrain in a seasonally moist, unstable air mass may<br \/>\n  produce locally strong gusts from wet microbursts through early evening, with Asheville and Greenville inside the Marginal Risk. In Arizona, another hot<br \/>\n  day builds steep lapse rates, and storms developing over higher terrain and spreading west may produce strong outflow gusts near Phoenix and Tucson.<\/p>\n<h2>How to Stay Safe During Midwest Severe Thunderstorms<\/h2>\n<p>Damaging straight-line wind is the primary hazard with today&#8217;s midwest severe thunderstorms, and it is the one that catches people out because it<br \/>\n  arrives without the visual warning a tornado gives. Winds capable of downing trees and power lines can hit fast with a forward-moving line. If a Severe<br \/>\n  Thunderstorm Warning is issued for your county, move indoors and away from windows immediately.<\/p>\n<p>Bring in or secure lightweight outdoor furniture, umbrellas, and anything a gust can throw, and do it before storms arrive rather than during. If you<br \/>\n  are in the Chicago, Milwaukee, Madison, or northern Indiana area, the window for midwest severe thunderstorms is this afternoon into the evening as the<br \/>\n  activity works east.<\/p>\n<p>In the Dakotas, hail is the hazard to plan around. Move vehicles into a garage or under solid cover before storms develop this evening, particularly<br \/>\n  near Pierre, Mitchell, Dickinson, and Williston, where the SPC carries its 15% hail probability and a conditional intensity area. If you are caught<br \/>\n  outdoors without shelter, protect your head.<\/p>\n<p>An isolated tornado cannot be ruled out through this evening across eastern Iowa, northern Illinois, and northern Indiana. Know where your shelter is<br \/>\n  before a warning is issued. Monitor <a href=\"https:\/\/ialert.com\/analysis.php#alerts\">active weather alerts<\/a> for your county through the afternoon and<br \/>\n  before a warning is issued. Monitor <a href=\"https:\/\/ialert.com\/analysis.php#alerts\">active weather alerts<\/a> for your county through the afternoon and<br \/>\n  evening, keep wireless emergency alerts enabled on your phone, and check your <a href=\"https:\/\/ialert.com\/forecast.php\">local weather forecast<\/a> for<br \/>\n  evening, keep wireless emergency alerts enabled on your phone, and check your <a href=\"https:\/\/ialert.com\/forecast.php\">local weather forecast<\/a> for<br \/>\n  timing specific to your area.<\/p>\n<h2>Midwest Severe Thunderstorms FAQ<\/h2>\n<h3>Which cities are in the Slight Risk for midwest severe thunderstorms today?<\/h3>\n<p>The Midwest corridor Slight Risk includes Chicago, Milwaukee, Madison, Kenosha, Rockford, Joliet, Peoria, Champaign, Davenport, Dubuque, Iowa City,<br \/>\n  Cedar Rapids, Waterloo, Rochester MN, Gary, South Bend, Lafayette, Fort Wayne, Kalamazoo, and Toledo. The separate Dakotas Slight Risk includes Pierre,<br \/>\n  Mitchell, Dickinson, and Williston. Boundaries shift with each SPC update, so treat the edge as approximate.<\/p>\n<h3>Are Minneapolis and Detroit in the midwest severe thunderstorms risk area?<\/h3>\n<p>Neither is in the Slight Risk. Minneapolis and St. Paul are in the General Thunderstorm area, outside even the Marginal Risk. Detroit, Ann Arbor,<br \/>\n  Lansing, Grand Rapids, Flint, and Saginaw are in the Marginal Risk (level 1 of 5), where isolated severe storms remain possible. The Slight Risk clips<br \/>\n  only southwest Lower Michigan near Kalamazoo before ending at Toledo.<\/p>\n<h3>How large could hail get in today&#8217;s storms?<\/h3>\n<p>The SPC does not give a maximum hail size for today&#8217;s midwest severe thunderstorms. It sets a 15% large hail probability in the Dakotas, where<br \/>\n  supercell wind profiles and steep low-level lapse rates support that threat, and adds a conditional intensity area near Dickinson where the higher end is<br \/>\n  possible. Across the Midwest corridor the hail probability is 5%, and Milwaukee, Madison, Rochester, and Toledo have no hail probability drawn at all.<\/p>\n<h3>Are tornadoes expected with today&#8217;s midwest severe thunderstorms?<\/h3>\n<p>An isolated tornado or two is possible. The SPC draws a 2% tornado probability over eastern Iowa, northern Illinois, and northern Indiana, including<br \/>\n  Chicago, Davenport, Dubuque, Gary, South Bend, and Fort Wayne. That is a real but limited threat, tied to enhanced low-level helicity along the surface<br \/>\n  boundary. No tornado probability is drawn over Wisconsin, Michigan, or the Dakotas.<\/p>\n<h3>When will storms arrive in the Chicago and Milwaukee area?<\/h3>\n<p>Morning convection from southern Minnesota and eastern Iowa is expected to spread east toward the Lake Michigan vicinity through the afternoon,<br \/>\n  reaching the Chicago and Milwaukee area during the afternoon hours, with midwest severe thunderstorms continuing into the evening. Storms may intensify as<br \/>\n  they move into the destabilizing air mass by midday.<\/p>\n<h3>Could the risk level be raised later today?<\/h3>\n<p>Yes. The SPC states that depending on how the morning convection evolves, higher probabilities may be needed for midwest severe thunderstorms in<br \/>\n  subsequent outlooks. Check the latest outlook rather than relying on the morning issuance if you are making plans for this evening.<\/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, issued 1215 AM CDT August<br \/>\n  9, 2026 (forecasters Leitman\/Moore)<\/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<br \/>\n  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\/services\/severe-weather-alerts.php\" style=\"background: #C41226; color: #ffffff; padding: 10px 22px; text-decoration: none;\n  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>Midwest severe thunderstorms threaten damaging winds and large hail from southern Minnesota and Iowa east to Michigan and Ohio on August 9.<span class=\"more\"> <a href=\"https:\/\/ialert.com\/blog\/news-events\/midwest-severe-thunderstorms-aug-9\/\">Read More&#8230;<\/a><\/span><\/p>\n","protected":false},"author":6,"featured_media":5481,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":"","rank_math_focus_keyword":"Midwest severe thunderstorms","rank_math_title":"Midwest Severe Thunderstorms: Chicago Wind Risk Aug 9","rank_math_description":"Midwest severe thunderstorms carry a 15% wind risk August 9, 2026. The SPC Slight Risk covers Chicago, Milwaukee, Madison, and Rockford."},"categories":[719],"tags":[772],"class_list":["post-5479","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-news-events","tag-spc-outlook"],"acf":[],"_links":{"self":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5479","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=5479"}],"version-history":[{"count":3,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5479\/revisions"}],"predecessor-version":[{"id":5484,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/posts\/5479\/revisions\/5484"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media\/5481"}],"wp:attachment":[{"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/media?parent=5479"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/categories?post=5479"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/ialert.com\/blog\/wp-json\/wp\/v2\/tags?post=5479"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}