Hurricane Hector

August 6th, 2018 |
NOAA-20 and Suomi NPP VIIRS Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 and Suomi NPP VIIRS Infrared Window (11.45 µm) images [click to enlarge]

* GOES-17 images shown here are preliminary and non-operational *

A toggle between NOAA-20 and Suomi NPP VIIRS Infrared Window (11.45 µm) images (above; courtesy of William Straka, CIMSS) showed the well-defined eye of Hurricane Hector after it had reached Category 4 intensity on 06 August 2018 (advisories: EPAC | CPAC).

GOES-17 “Red” Visible (0.64 µm) images (below) revealed cloud-top gravity waves within the eyewall region of the storm, along with thin filaments of transverse banding in the northern semicircle farther from the eye.

GOES-17

GOES-17 “Red” Visible (0.64 µm) images [click to play animation | MP4]

GOES-15 (GOES-West) Visible (0.63 µm) and Infrared Window (10.7 µm) images (below) showed that eyewall cloud-top infrared brightness temperatures were in the -70 to -80ºC range (black to white enhancement).

GOES-15 Visible (0.63 µm, left) and Infrared Window (10.7 µm, right) images [click to play animation | MP4]

GOES-15 Visible (0.63 µm, left) and Infrared Window (10.7 µm, right) images [click to play animation | MP4]

A magnified view of GOES-15 Visible images (below) revealed mesovortices within the eye of Hector.

GOES-15 Visible (0.63 µm) images [click to play animation | MP4]

GOES-15 Visible (0.63 µm) images [click to play animation | MP4]

Metop ASCAT surface scatterometer winds (below) surrounding the eye were near 70 knots around 1930 UTC.

GOES-15 Infrared Window (10.7 µm) image and Metop ASCAT surface scatterometer winds [click to enlarge]

GOES-15 Infrared Window (10.7 µm) image and Metop ASCAT surface scatterometer winds [click to enlarge]

The MIMIC-TC morphed microwave product (below) showed that Hector underwent an eyewall replacement cycle early in the day on 05 August, and then maintained a well-defined eye as it subsequently strengthened to a high-end Category 4 intensity on 06 August (ADT | SATCON).

MIMIC-TC morphed microwave product [click to play animation]

MIMIC-TC morphed microwave product [click to play animation]

===== 07 August Update =====

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images [click to enlarge]

A nighttime NOAA-20 VIIRS Day/Night Band (0.7 µm) image (above) revealed the presence of mesospheric airglow waves (reference) propagating northwestward away from Category 4 Hurricane Hector on 07 August. Note that these high-altitude waves were not apparent on the corresponding Infrared Window (11.45 µm) image.