Post-Tropical Cyclone Hermine

September 5th, 2016 |

GOES-13 Visible (0.63 µm) images, with buoy/ship reports plotted in yellow [click to play animation]

GOES-13 Visible (0.63 µm) images, with buoy/ship reports plotted in yellow [click to play animation]

GOES-13 (GOES-East) Visible (0.63 µm) images showed that the circulation of Post-Tropical Cyclone Hermine (NHC discussions) persisted off the US East Coast on 04 September (above; also available as an MP4 animation) and on 05 September 2016 (below; also available as an MP4 animation). On 04 September, the Royal Caribbean cruise ship Anthem of the Seas sustained some minor damage as it encountered strong winds and high waves in the northeastern quadrant of the storm (ship location | satellite images) while sailing from New Jersey to Bermuda.  Also of particular interest were the pair of mesovortices seen rotating around the main circulation center of the storm on 05 September. The GOES-13 satellite had remained in Rapid Scan Operations (RSO) mode during this period, providing images as frequently as every 5-7 minutes.

GOES-13 Visible (0.63 µm) images, with buoy/ship reports plotted in yellow [click to play animation]

GOES-13 Visible (0.63 µm) images, with buoy/ship reports plotted in yellow [click to play animation]

===== 06 September Update =====

GOES-13 Visible (0.63 µm) images, with surface/buoy/ship data plotted in yellow [click to play animation]

GOES-13 Visible (0.63 µm) images, with surface/buoy/ship data plotted in yellow [click to play animation]

On 06 September, the circulation of Post-Tropical Cyclone Hermine continued to move very slowly westward toward the Northeast US coast as it gradually weakened (above; also available as an MP4 animation). A 1600 UTC GOES-13 Visible image with plots of Metop ASCAT winds along with surface/buoy/ship reports is shown below — the maximum ASCAT surface scatterometer wind speeds were 33 knots in the western semicircle of the storm.

GOES-13 Visible (0.63 µm) image at 1600 UTC, with ASCAT winds and surface/buoy/ship reports [click to enlarge]

GOES-13 Visible (0.63 µm) image at 1600 UTC, with ASCAT winds and surface/buoy/ship reports [click to enlarge]

As of 18 UTC, all coastal Tropical Storm Warnings were discontinued by the National Hurricane Center (final advisory).

===== 07 September Update =====

MIMIC Total Precipitable Water product [click to play animation]

MIMIC Total Precipitable Water product [click to play animation]

An animation of hourly MIMIC Total Precipitable Water (TPW) product images covering the 04-07 September period {above) showed that the remnant circulation of what was formerly Post-Tropical Cyclone Hermine still contained relatively high values of TPW (in the 50-60 mm or 2.0-2.4 inch range) as it edged closer to the coast on 07 September.