{"id":66730,"date":"2025-09-10T23:59:00","date_gmt":"2025-09-10T23:59:00","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=66730"},"modified":"2025-09-12T21:24:59","modified_gmt":"2025-09-12T21:24:59","slug":"post-tropical-cyclone-kiko-north-of-hawaii","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/66730","title":{"rendered":"Post-Tropical Cyclone Kiko north of Hawai\u2019i"},"content":{"rendered":"<p><div style=\"width: 3002px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_goes18_infrared_glmFlashExtentDensity_PTC_Kiko.mp4\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_1741utc_goes18_infrared_glmFlashExtentDensity_PTC_Kiko.png\" width=\"2992\" height=\"1722\" \/><\/a><p class=\"wp-caption-text\">5-minute GOES-18 &#8220;Clean&#8221; Infrared Window (10.3 \u00b5m) images with an overlay of GLM Flash Extent Density, from 0901 UTC on 10 September to 0001 UTC on 11 September [click to play MP4 animation]<\/p><\/div>5-minute CONUS Sector GOES-18 <em>(GOES-West)<\/em> Infrared images <em><strong>(above)<\/strong><\/em> revealed the exposed low-level circulation center (LLCC) of Tropical Storm Kiko as the system continued to weaken north of the Hawaiian island of Oahu, and downgraded to a Post-Tropical Cyclone at <a href=\"https:\/\/www.nhc.noaa.gov\/archive\/2025\/ep11\/ep112025.discus.042.shtml\"><strong>1500 UTC<\/strong><\/a> on 10 September 2025. Clusters of deep convection developed north of the LLCC after 1400 UTC, which exhibited abundant satellite-detected lightning activity. Note that the LLCC passed just to the east of a semi-stationary yellow ship report around <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_1301utc_goes18_infrared_PTC_Kiko.png\"><strong>1301 UTC<\/strong><\/a> &#8212; that was the <a href=\"https:\/\/en.wikipedia.org\/wiki\/RV_Kilo_Moana\"><strong>RV Kilo Moana<\/strong><\/a> (Maritime call sign <a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_1301utc_goes18_infrared_WDA7827.png\"><strong>WDA7827<\/strong><\/a>), an oceanographic research vessel.<\/p>\n<p>A comparison of GOES-18 Infrared and Visible images (<em><strong>below)<\/strong><\/em> showed that the LLCC was more distinct in the higher spatial resolution Visible imagery &#8212; however, the LLCC eventually moved beneath the canopy of growing thunderstorms after 1900 UTC, making it impossible to further track.<\/p>\n<p><div style=\"width: 3002px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_goes18_infrared_visible_PTC_Kiko.mp4\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_1801utc_g18_vis_ir_PTC_Kiko.png\" width=\"2992\" height=\"1722\" \/><\/a><p class=\"wp-caption-text\">5-minute GOES-18 \u201cClean\u201d Infrared Window (10.3 \u00b5m, left) and \u201cRed&#8221; Visible (0.64 \u00b5m, right) images, from 1621 UTC on 10 September to 0001 UTC on 11 September [click to play MP4 animation]<\/p><\/div>The LLCC was also very apparent in GCOM-W1 AMSR2 Microwave imagery (<a href=\"http:\/\/soest-hcc1.hcc.hawaii.edu\/browser\/11E_KIKO\/:gcom-w1+amsr2+btemp_36.5h\/\"><strong>source<\/strong><\/a>) not far north-northeast of Oahu at 1150 UTC <em><strong>(below)<\/strong><\/em>.<\/p>\n<p><div style=\"width: 1034px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/gcom-w1_amsr2_btemp_36.5h_20250910_115000_11E_KIKO.png\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/gcom-w1_amsr2_btemp_36.5h_20250910_115000_11E_KIKO.png\" width=\"1024\" height=\"1024\" \/><\/a><p class=\"wp-caption-text\">GCOM-W1 AMSR2 Microwave (36.5 GHz) image at 1150 UTC on 10 September [click to enlarge]<\/p><\/div>ASCAT surface scatterometer winds (<a href=\"https:\/\/manati.star.nesdis.noaa.gov\/datasets\/ASCATBData.php\"><strong>source<\/strong><\/a>) from Metop-B (at 0735 UTC, when Kiko was still a Tropical Storm) and Metop-C (at 2051 UTC, about 6 hours after Kiko was downgraded to a Post-Tropical Cyclone) are shown below. The depiction of the LLCC wind field was seen to degrade during the ~13 hour period between the two ASCAT images.<\/p>\n<div style=\"width: 750px\" class=\"wp-caption aligncenter\"><img loading=\"lazy\" decoding=\"async\" class=\"size-medium\" src=\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/250910_metopB_metopC_ascat_Kiko_anim.gif\" width=\"740\" height=\"650\" \/><p class=\"wp-caption-text\">ASCAT winds from Metop-B (at 0735 UTC) and Metop-C (at 2051 UTC) on 10 September<\/p><\/div>\n","protected":false},"excerpt":{"rendered":"<p>5-minute CONUS Sector GOES-18 (GOES-West) Infrared images (above) revealed the exposed low-level circulation center (LLCC) of Tropical Storm Kiko as the system continued to weaken north of the Hawaiian island of Oahu, and downgraded to a Post-Tropical Cyclone at 1500 UTC on 10 September 2025. Clusters of deep convection developed north of the LLCC after [&hellip;]<\/p>\n","protected":false},"author":18,"featured_media":66736,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[81,76,114,30,58,79,25,2],"tags":[],"class_list":["post-66730","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-gcom-w1","category-glm","category-goes-18","category-lightning","category-metop","category-microwave","category-satellite-winds","category-tropical-cyclones"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/66730","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/users\/18"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=66730"}],"version-history":[{"count":25,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/66730\/revisions"}],"predecessor-version":[{"id":66766,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/66730\/revisions\/66766"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/66736"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=66730"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=66730"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=66730"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}