{"id":2265,"date":"2026-09-25T13:11:00","date_gmt":"2026-09-25T04:11:00","guid":{"rendered":"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-en\/"},"modified":"2026-09-25T13:11:00","modified_gmt":"2026-09-25T04:11:00","slug":"2026-09-25-hurricane-polo-rapid-intensification-en","status":"publish","type":"briefing","link":"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-en\/","title":{"rendered":"Hurricane Polo intensified by 90 kt in 24 hours and reached Category 5"},"content":{"rendered":"<p><strong>2026-09-25 13:11 KST<\/strong><\/p>\n<p>The US National Hurricane Center called the 24-hour, 90-kt increase \u201ctruly remarkable\u201d; aircraft analysis later put Polo briefly at 180 mph with a 892-hPa centre.<\/p>\n<p>At the 24 September 8 p.m. MST checkpoint it was a 150-mph Category 4 moving west offshore, and both intensity and track could still change.<\/p>\n<h2>How large was 90 kt<\/h2>\n<p>One knot is 1.852 km\/h, so the daily increase was about 167 km\/h. That is three times the NHC rapid-intensification threshold of 30 kt in 24 hours. The operational estimate may be adjusted in post-season analysis.<\/p>\n<h2>Why did intensity fluctuate<\/h2>\n<p>Powerful hurricanes can form an outer eyewall that replaces the inner one. Peak winds may temporarily ease while the wind field expands. Dropping from Category 5 to 4 therefore reflected structural change, not instant disappearance.<\/p>\n<h2>Hazards for Mexico<\/h2>\n<p>The centre was expected to remain offshore, but outer rainbands affected Guerrero, Michoac\u00e1n, Colima and Jalisco. Authorities prepared for flooding, landslides, rising rivers and dangerous surf. Offshore centres can still cause damage.<\/p>\n<figure class=\"wp-block-image size-full\"><img decoding=\"async\" src=\"https:\/\/onepress.co.kr\/wp-content\/uploads\/2026\/09\/hurricane-polo-rapid-intensification-en.png\" alt=\"Hurricane Polo intensified by 90 kt in 24 hours and reached Category 5\" loading=\"lazy\" \/><figcaption class=\"op-briefing-image-caption\">AI-generated explanatory image of Hurricane Polo offshore; it is not an actual satellite observation or forecast map.<\/figcaption><\/figure>\n<h2>What the category omits<\/h2>\n<p>The Saffir\u2013Simpson scale uses one-minute maximum sustained wind. It does not combine rainfall, flooding, landslides or waves, so crossing the 157-mph Category 5 line does not switch those hazards on or off.<\/p>\n<h2>Forecasts move<\/h2>\n<p>The latest 24 September display showed Polo heading west away from the coast while allowing renewed strengthening. This article cannot replace local evacuation advice; NHC, Conagua and civil-protection alerts take priority.<\/p>\n<h2>Next checks<\/h2>\n<p>NHC issues regular advisories and intermediates. Track wind radii, rainfall, waves, landslide alerts and local orders together. Final peak intensity will be reanalysed in the post-season cyclone report.<\/p>\n<h2>Primary sources and independent checks<\/h2>\n<p>Official release: <a href=\"https:\/\/www.nhc.noaa.gov\/archive\/2026\/ep17\/ep172026.discus.007.shtml\" target=\"_blank\" rel=\"noopener noreferrer\">NHC rapid-intensification discussion<\/a><\/p>\n<p>Earlier official research plan: <a href=\"https:\/\/www.nhc.noaa.gov\/archive\/2026\/POLO.shtml\" target=\"_blank\" rel=\"noopener noreferrer\">NHC Polo advisory archive<\/a><\/p>\n<p>Independent report: <a href=\"https:\/\/www.gob.mx\/conagua\/prensa\/el-huracan-polo-mantiene-su-desplazamiento-lento-frente-a-las-costas-de-guerrero-y-colima-436135\" target=\"_blank\" rel=\"noopener noreferrer\">Mexico Conagua advisory<\/a><\/p>\n<p>Additional official source: <a href=\"https:\/\/apnews.com\/article\/a6c1c226c878a236442a8e1a7f37211b\" target=\"_blank\" rel=\"noopener noreferrer\">AP independent report<\/a><\/p>\n<h2>Read in other languages<\/h2>\n<p><a href=\"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-ko\/\">\ud55c\uad6d\uc5b4<\/a> \u00b7 <a href=\"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-en\/\">English<\/a> \u00b7 <a href=\"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-es\/\">Espa\u00f1ol<\/a> \u00b7 <a href=\"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-ja\/\">\u65e5\u672c\u8a9e<\/a> \u00b7 <a href=\"https:\/\/onepress.co.kr\/index.php\/briefing\/2026-09-25-hurricane-polo-rapid-intensification-vi\/\">Ti\u1ebfng Vi\u1ec7t<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Hurricane Polo off Mexico\u2019s Pacific coast gained about 90 kt in maximum winds over 24 hours and reached Category 5 on 22 September. It fell to Category 4 after an eyewall replacement on 24 September, but rain, surf and coastal hazards did not vanish with the category change.<\/p>\n","protected":false},"featured_media":0,"template":"","meta":[],"class_list":["post-2265","briefing","type-briefing","status-publish","hentry"],"_links":{"self":[{"href":"https:\/\/onepress.co.kr\/index.php\/wp-json\/wp\/v2\/briefing\/2265","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/onepress.co.kr\/index.php\/wp-json\/wp\/v2\/briefing"}],"about":[{"href":"https:\/\/onepress.co.kr\/index.php\/wp-json\/wp\/v2\/types\/briefing"}],"wp:attachment":[{"href":"https:\/\/onepress.co.kr\/index.php\/wp-json\/wp\/v2\/media?parent=2265"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}