{"id":51356,"date":"2023-03-30T20:59:28","date_gmt":"2023-03-30T20:59:28","guid":{"rendered":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/?p=51356"},"modified":"2023-03-31T19:15:05","modified_gmt":"2023-03-31T19:15:05","slug":"sar-winds-over-cyclone-hernan-in-the-south-indian-ocean","status":"publish","type":"post","link":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/archives\/51356","title":{"rendered":"SAR Winds over Cyclone Herman in the south Indian Ocean"},"content":{"rendered":"\n

Himawari-9 imagery for the hour surrounding an RCM-1<\/a> pass over the center of Severe Tropical Cyclone Herman, below, shows strong convection (with widespread brightness temperatures colder than -85o<\/sup>C — light purple in this enhancement — with isolated pixel values cooler than -90o<\/sup>C — in purple). Peak Synthetic Aperture Radar (SAR) winds from the Radarsat Constellation Mission-1 satellite exceeded 80 m\/s! Click here to view the storm track<\/a>, and text describing the storm<\/a>, both from this Australian Bureau of Meteorology website<\/a>. (Here’s the 1-hour animation without the SAR winds<\/a>).<\/p>\n\n\n\n

\"\"<\/a>
Himawari-9 Clean Window (Band 13, 10.4 ) from 1100-1200 UTC on 30 March 2023 (Click to enlarge). SAR WInds from RCM1 are overlain at 1120 UTC<\/figcaption><\/figure>\n\n\n\n

A zoomed-in picture of the SAR wind analysis is shown below. The data can also be viewed at this SAR Tropical Cyclone site specific to Herman<\/a> (Direct link to image<\/a>). Strong winds encircle the entire eye.<\/p>\n\n\n\n

\"\"
RCM-1 SAR Wind analysis, 1119 UTC on 30 March 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

The image below, from the Australian Bureau of Meteorology ‘MetEye<\/a>‘ website, shows Herman’s track relative to Australia.<\/p>\n\n\n\n

\"\"<\/a>
MetEye screencapture, 2035 UTC on 30 March 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

Herman is moving through an atmosphere of low shear, as shown below (image from this site<\/a>), and is over waters with sea-surface temperatures of 27-28o<\/sup>C (not shown).<\/p>\n\n\n\n

\"\"
200-850 mb wind analysis, 1800 UTC on 30 March 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

The MIMIC-TC animation below (from this site<\/a>) shows the closing off of the eyewall that accompanied Herman’s rapid intensification<\/p>\n\n\n\n

\"\"
MIMIC TC, 0000 30 March – 0000 UTC on 31 March 2023 (Click to enlarge)<\/figcaption><\/figure>\n\n\n\n

More information on Herman is available at the Joint Typhoon Warning Center<\/a>. Also, note that the Target Sector<\/a> from JMA<\/a> Is over Herman (link<\/a>).<\/p>\n\n\n

__________________________________________________________________<\/p>\n

\"\"<\/a>

JMA Himawari-9 Infrared Window (10.4 \u00b5m) images, from 0902 UTC on 30 March to 0132 UTC on 31 March (credit: Scott Bachmeier, CIMSS) [click to play animated GIF | MP4<\/strong><\/a>]<\/p><\/div>\n

2.5-minute Target Sector Himawari-9 Infrared Window (10.4 \u00b5m) images (above)<\/strong><\/em> showed Herman as it rapidly intensified to a Category 3 storm, eventually displaying a pinhole eye. Note that the eye exhibited some trochoidal motion (wobble) as the storm moved south-southeastward — a behavior often seen with intense tropical cyclones.<\/p>\n

===== 31 March Update =====<\/strong><\/p>\n

<\/a>

JMA Himawari-9 Infrared Window (10.4 \u00b5m) images, from 0602 UTC on 31 March to 1707 UTC on 31 March (credit: Scott Bachmeier, CIMSS) [click to play animated GIF | MP4<\/strong><\/a>]<\/p><\/div>\n

Herman continued its remarkable rapid intensification on 31 March, with 2.5-minute Target Sector Himawari-9 Infrared images showing an intermittent open eye persisting past 15 UTC (above)<\/strong><\/em>.<\/p>\n

A Himawari-9 Infrared – Water Vapor Difference product from the CIMSS Tropical Cyclones<\/strong><\/a> site (below)<\/strong><\/em> displayed large values (shades of red to violet) — indicating that cloud tops within the eyewall were overshooting the tropopause (reference<\/strong><\/a>).<\/p>\n

<\/a>

Himawari-9 Infrared – Water Vapor Difference product<\/p><\/div>","protected":false},"excerpt":{"rendered":"

Himawari-9 imagery for the hour surrounding an RCM-1 pass over the center of Severe Tropical Cyclone Herman, below, shows strong convection (with widespread brightness temperatures colder than -85oC — light purple in this enhancement — with isolated pixel values cooler than -90oC — in purple). Peak Synthetic Aperture Radar (SAR) winds from the Radarsat Constellation […]<\/p>\n","protected":false},"author":19,"featured_media":51363,"comment_status":"closed","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"_acf_changed":false,"footnotes":""},"categories":[73,79,104,25],"tags":[],"class_list":["post-51356","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-himawari-9","category-microwave","category-sar","category-satellite-winds"],"acf":[],"_links":{"self":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/51356","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\/19"}],"replies":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/comments?post=51356"}],"version-history":[{"count":19,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/51356\/revisions"}],"predecessor-version":[{"id":51426,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/posts\/51356\/revisions\/51426"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media\/51363"}],"wp:attachment":[{"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/media?parent=51356"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/categories?post=51356"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/wp-json\/wp\/v2\/tags?post=51356"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}