Hurricane Humberto reaches Category 5 intensity in the western Atlantic
1-minute Mesoscale Domain Sector GOES-19 (GOES-East) Visible images (above) showed Hurricane Humberto as it intensified from a Category 4 to a Category 5 storm on 27 September 2025 (Humberto became the second Category 5 storm in the Atlantic Basin this season — with Erin being the first). Low-altitude mesovortices were evident within the eye, along with cloud-top gravity waves in the surrounding eyewall region.In an animation of 1-minute GOES-19 Infrared images (below), the eye began to exhibit a slight amount of trochoidal motion as Humberto intensified later in the day.
A DMSP-18 SSMIS Microwave image at 2013 UTC — shortly before Humberto was upgraded to Category 5 at 2100 UTC (below) displayed a fully-closed inner eyewall.
DMSP-18 SSMIS Microwave image at 2013 UTC on 27 September
Humberto’s intensification to Category 5 occurred as the hurricane was moving through an environment of weak deep-layer wind shear (below) and traversing warm water.

GOES-19 Infrared images with an overlay of contours and streamlines of deep-layer wind shear at 2300 UTC on 27 September
Microwave, wind shear and sea surface temperature imagery was sourced from the CIMSS Tropical Cyclones site.
A RCM-2 Synthetic Aperture Radar (SAR) image (source) at 2214 UTC (below) sensed wind speeds as high as 126.94 kt in the NW quadrant of Humberto.