Hurricane Teddy rapidly intensifies to a Category 4 storm

September 17th, 2020 |

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (with and without an overlay of GLM Flash Extent Density) [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images — with and without an overlay of GLM Flash Extent Density (above) showed Hurricane Teddy as it rapidly intensified (ADT | SATCON ) to a Category 4 storm on 17 September 2020. The coldest cloud-top infrared brightness temperatures were in the -80 to -85ºC range.

Metep-A ASCAT surface scatterometer wind speeds were as high as 74 knots in the northwestern portion  of the eyewall (below).

GOES-16 “Red” Visible (0.64 µm) image, with plots of Metop-A ASCAT winds [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) image, with plots of Metop-A ASCAT winds [click to enlarge]

Microwave (85 GHz) DMSP-17 (at 1023 UTC), GMI (at 1720 UTC) and DMSP-18 (at 2034 UTC) images from the CIMSS Tropical Cyclones site are shown below.

DMSP-17 SSMI Microwave (85 GHz) image at 1023 UTC [click to enlarge]

DMSP-17 SSMI Microwave (85 GHz) image at 1023 UTC [click to enlarge]

GMI Microwave (85 GHz) image at 1720 UTC [click to enlarge]

GMI Microwave (85 GHz) image at 1720 UTC [click to enlarge]

DMSP-18 SSMI Microwave (85 GHz) image at 2034 UTC [click to enlarge]

DMSP-18 SSMI Microwave (85 GHz) image at 2034 UTC [click to enlarge]

Hurricane Genevieve in the East Pacific Ocean

August 18th, 2020 |

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images [click to play animation | MP4]

 1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) displayed the well-defined eye of Category 4 Hurricane Genevieve in the East Pacific Ocean (off the west coast of Mexico) on 18 August 2020. Genevieve underwent a period of rapid intensification during the pre-dawn hours that day (ADT plot).

A GOES-16 Visible image at 1617 UTC (below) includes plots of Metop-A ASCAT scatterometer surface winds — the highest wind was 69 knots just northeast of the storm center.

GOES-16 “Red” Visible (0.64 µm) image, with plots of ASCAT scatterometer surface winds [click to enlarge]

GOES-16 “Red” Visible (0.64 µm) image, with plots of ASCAT scatterometer surface winds [click to enlarge]

Tropical Storm Arthur forms off the coast of Florida

May 16th, 2020 |

GOES-16

GOES-16 “Clean” Infrared Window (10.35 µm) images, with and without an overlay of GLM Flash Extent Density [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm) images, with and without an overlay of GLM Flash Extent Density (above) showed the period leading up to the formation of Tropical Storm Arthur during the evening of 16 May 2020 (at 03 UTC on 17 May) — making it the first tropical cyclone of the season in the Atlantic Basin. There were periods of lightning activity within the elongated cluster of deep convection east of the storm center.

==== 17 May Update =====

GOES-16 "Red" Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images [click to play animation | MP4]

During most of the day on 17 May, the low-level circulation center of Arthur was easily seen in 1-minute GOES-16 “Red” Visible (0.64 µm) images (above).

The corresponding GOES-16 Infrared images — with and without an overlay of GLM Flash Extent Density — are shown below.

GOES-16 "Clean" Infrared Window (10.35 µm) images, with and without an overlay of GLM Flash Extent Density [click to play animation | MP4]

GOES-16 “Clean” Infrared Window (10.35 µm) images, with and without an overlay of GLM Flash Extent Density [click to play animation | MP4]

===== 18 May Update =====

GOES-16 "Red" Visible (0.64 µm) images [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images [click to play animation | MP4]

1-minute GOES-16 Visible images (above) showed that the low-level circulation center of Arthur became exposed during the day on 18 May. The center of Arthur passed very close to the Diamond Shoals buoy just off the coast of North Carolina (wind/pressure plot).

GOES-16  Visible images with plots of Metop ASCAT winds (below) revealed surface winds as high as 37 knots just east of the center of Arthur.

GOES-16 "Red" Visible (0.64 µm) images, with plots of Metop ASCAT winds [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images, with plots of Metop ASCAT winds [click to play animation | MP4]

Lake Erie mesovortex, and an undular bore over the Dakotas

March 24th, 2020 |

GOES-16

GOES-16 “Red” Visible (0.64 µm) images [click to play animation | MP4]

Two interesting small-scale features were seen in GOES-16 (GOES-East) imagery on 24 March 2020. First of all, 1-minute Mesoscale Domain Sector “Red” Visible (0.64 µm) images (above) showed a mesovortex that was migrating west-northwestward across Lake Erie during the day. This feature had a diameter of around 10 miles — such a small-scale circulation was not captured by Metop-A ASCAT surface scatterometer data.

During the preceding overnight hours, an early signature of the mesovortex was evident in Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and “Fog product” Brightness Temperature Difference (BTD) images at 0806 UTC (below).

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and "Fog product" Brightness Temperature Difference (BTD) images [click to enlarge]

Suomi NPP VIIRS Shortwave Infrared (3.74 µm) and “Fog product” Brightness Temperature Difference (BTD) images [click to enlarge]

The second feature of interest was a pre-cold-frontal undular bore that was moving eastward across the Dakotas, as seen in Day Cloud Phase Distinction Red-Green-Blue (RGB) images (below).

GOES-16 Day Cloud Phase Distinction RGB images [click to play animation | MP4]

GOES-16 Day Cloud Phase Distinction RGB images [click to play animation | MP4]