![](\"https:\/\/cimss.ssec.wisc.edu\/satellite-blog\/images\/2025\/09\/G19_VIS_HUMBERTO_27SEP2025_loop_GOES-19_2025270_141053_2025270_212153.gif\")
<\/a>1-minute GOES-19 Visible images, from 1410-2121 UTC on 27 September [click to play animated GIF]<\/p><\/div>1-minute Mesoscale Domain Sector GOES-19 (GOES-East)<\/em> Visible images (above)<\/em><\/strong> showed Hurricane Humberto<\/strong><\/a> as it intensified from a Category 4 to a Category 5<\/strong><\/a> storm on 27 September 2025 (Humberto became the second Category 5 storm in the Atlantic Basin this season — with Erin<\/strong><\/a> being the first). Low-altitude mesovortices were evident within the eye, along with cloud-top gravity waves in the surrounding eyewall region.<\/p>\n In an animation of 1-minute GOES-19 Infrared images (below)<\/strong><\/em>, the eye began to exhibit a slight amount of trochoidal motion as Humberto intensified later in the day.<\/p>\n 1-minute GOES-19 Infrared images, from 1410-2300 UTC on 27 September [click to play animated GIF]<\/p><\/div>A DMSP-18 SSMIS Microwave image at 2013 UTC — shortly before Humberto was upgraded to Category 5 at 2100 UTC (below)<\/strong><\/em> displayed a fully-closed inner eyewall.<\/p>\n DMSP-18 SSMIS Microwave image at 2013 UTC on 27 September<\/p><\/div>\n Humberto’s intensification to Category 5 occurred as the hurricane was moving through an environment of weak deep-layer wind shear<\/strong><\/a> (below)<\/strong><\/em> and traversing warm water<\/strong><\/a>.<\/p>\n GOES-19 Infrared images with an overlay of contours and streamlines of deep-layer wind shear at 2300 UTC on 27 September<\/p><\/div>\n Microwave, wind shear and sea surface temperature imagery was sourced from the CIMSS Tropical Cyclones<\/strong><\/a> site.<\/p>\n A RCM-2 Synthetic Aperture Radar (SAR) image (source<\/strong><\/a>) at 2214 UTC (below)<\/strong><\/em> sensed wind speeds as high as 126.94 kt in the NW quadrant of Humberto.<\/p>\n<\/a>