Hurricane Henriette

August 8th, 2013 |
Suomi NPP VIIRS 11.45 µm IR images

Suomi NPP VIIRS 11.45 µm IR images

A sequence of three AWIPS images of 1-km resolution Suomi NPP VIIRS 11.45 µm IR data (above) showed the relatively compact cloud structure associated with Hurricane Henriette over the Eastern Pacific Ocean during the 07 August – 08 August 2013 period. Cloud-top IR brightness temperatures were as cold as -83 C (violet color enhancement) on the 08 August/11:12 UTC image. Henriette also exhibited a small eye on the 11:12 UTC and 22:26 UTC images on 08 August.

On a night-time comparison of Suomi NPP VIIRS 0.7 µm Day/Night Band  and 11.45 µm IR images at 11:15 UTC (below), it is interesting to point out that the eye could still be faintly identified on the Day/Night Band image, even though there was only a minimal amount of illumination from airglow alone (the Moon was in its early Waxing Crescent phase, at only 1-3% of full, but was actually below the horizon for this particular image).

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR channel images

The compact eye of Henriette was well-defined on a comparison of VIIRS 0.64 µm visible channel and 11.45 µm IR channel images at 22:26 UTC (below). Henriette was near its maximum intensity of 90 knots around this time.

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images

A 1-km resolution GOES-15 0.63 µm visible channel image with an overlay of ASCAT surface scatterometer winds from the CIMSS Tropical Cyclones site (below) also showed a good presentation of the eye and the surface wind flow associated with the Henriette.

GOES-15 0.63 µm visible channel image with ASCAT surface scatterometer winds

GOES-15 0.63 µm visible channel image with ASCAT surface scatterometer winds

An animation of GOES-15 10.7 µm IR channel images (below) revealed that the eye was becoming less obvious after about 00 UTC on 09 August.

GOES-15 10.7 µm IR channel images

GOES-15 10.7 µm IR channel images

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