Subtropical Storm Alberto gradually intensifies

May 27th, 2018 |

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 toggle between NOAA-20 VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images at 0731 UTC or 3:31 am local time (above; courtesy of William Straka, CIMSS) showed Subtropical Storm Alberto when it was centered off the southwest coast of Florida on 27 May 2018. Note that NOAA-20 imagery is still considered preliminary and non-operational.

GOES-16 (GOES-East) Low-level (7.3 µm), Mid-level (6.9 µm) and Upper-level (6.2 µm) Water Vapor images (below) revealed that dry air was wrapping into the circulation of Alberto during the day.

GOES-16 Low-level (7.3 µm, left), Mid-level (6.9 µm, center) and Upper-level (6.2 µm, right) Water Vapor images [click to play MP4 animation]

1-minute Mesoscale Domain Sector GOES-16 “Red” Visible (0.64 µm) and “Clean” infrared Window (10.3 µm) images (below) showed that the low-level circulation center of Alberto became partially exposed, and the areal coverage and intensity of deep convection diminished somewhat during the day as the dry air was being entrained into the storm.

GOES-16 “Red” Visible (0.64 µm) images, with hourly plots of ship and buoy reports [click to play MP4 animation]

GOES-16 “Clean” Infrared Window (10.3 µm) images, with hourly plots of ship and buoy reports [click to play MP4 animation]

===== 29 May Update =====

Composite of GOES-16 1-minute Mesoscale Domain Sector “Clean” Infrared Window (10.3 µm) images for the period 1630 UTC on 26 May to 1000 UTC on 29 May 2018 [click to play YouTube video]

A composite of GOES-16 1-minute Mesoscale Domain Sector “Clean” Infrared Window (10.3 µm) images for the period 1630 UTC on 26 May to 1000 UTC on 29 May 2018 (above; courtesy of Pete Pokrandt, AOS) showed Subtropical Storm Alberto as it moved northward across the Gulf of Mexico and eventually inland over Alabama.