Hurricane Darby in the East Pacific Ocean

July 11th, 2022 |

GOES-17 “Red” Visible (0.64 µm, top) and “Clean” Infrared Window (10.35 µm, bottom) images [click to play animated GIF | MP4]

1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed the evolution of the eye of Hurricane Darby as it moved westward across the East Pacific Ocean on 11 July 2022. Mesovortices were evident within the eye, along with a stadium effect eye structure — as Darby ended its period of rapid intensification and leveled off as a Category 4 storm (ADT | SATCON). Darby was moving through an environment of low wind shear and across relatively warm water (SST | OHC), factors which favored intensification.

A NOAA-20 VIIRS Infrared Window (11.45 µm) image from RealEarth (below) revealed an arc of slightly colder cloud tops (shades of white within dark black) in the northern portion of the eyewall.

NOAA-20 VIIRS Infrared Window (11.45 µm ) image at 2129 UTC [click to enlarge]

A NOAA-20 ATMS Microwave (183 GHz) image from the CIMSS Tropical Cyclones site (below) also showed the compact eye, along with a band of precipitation spiraling northward.

NOAA-20 ATMS Microwave (183 GHz) image at 2129 UTC [click to enlarge]

SAR Winds over the tropical Pacific Ocean

July 11th, 2022 |
GOES-17 ABI Band 13 (Clean Window Infrared, 10.3 µm), 0400-0510 UTC on 11 July 2022, along with SAR Wind observations at 0513 UTC (Click to enlarge)

This NOAA/NESDIS website shows small footprints where SAR observations of ice and wind (from the RADARSAT Constellation Mission — RCM — satellites and from Sentinel) are available. AWIPS-ready data are also available from an ftp site. Consider the animation of GOES-17 Band 13 imagery above, just south to the Equator, and to the west of 160oW longitude. The slightly cooler brightness temperatures at the eastern edge of the arc of clouds moving to the west is associated with two patches of strong surface winds. The toggle below zooms in on the region of winds. Surface wind speeds are close to 15 m s-1 with this weak line of tropical convection.

GOES_17 ABI Band 13 (Clean Window infrared, 10.3 µm) at 0510 UTC and RCM1 SAR Winds at 0513 UTC, 11 July 2022 (Click to enlarge)