Severe convection « CIMSS Satellite Blog

Severe thunderstorms in northern Minnesota

July 26th, 2021 | Scott Bachmeier

GOES-16 “Red” Visible (0.64 µm) images (top) and “Clean” Infrared Window (10.35 µm) images (bottom), with plots of SPC Storm Reports [click to play animation | MP4]

1–minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images and “Clean” Infrared Window (10.35 µm) images (above) include time-matched plots of SPC Storm Reports produced by supercell thunderstorms that moved east-southeastward across northern Minnesota during the afternoon and early evening hours on 26 July 2021. Severe reports included a tornado at 2213 UTC and hail as large as to 3.0 inches in diameter at 2334 UTC. These storms developed near and north of a warm/stationary frontal boundary (surface analyses).

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25th Anniversary of the Oakfield, Wisconsin F5 tornado

July 18th, 2021 | Scott Bachmeier

An F5 tornado struck the village of Oakfield, Wisconsin late in the day on 18 July 1996 (NWS Milwaukee story). An animation of GOES-8 (GOES-East) Visible images (below) showed the development of supercell thunderstorms as they moved east-southeastward across the area. Oakfield is located just southwest of Fond du Lac (KFLD), and is denoted by the yellow ‘+’ symbol on the images. Overshooting tops were evident on these thunderstorms.

GOES-8 Visible images [click to play animation | MP4]

The corresponding GOES-8 Infrared Window images (below) revealed cloud-top infrared brightness temperatures as cold as -63.6ºC (darker shades of red) at 2345 UTC, which was approximately 30 minutes prior to the tornado moving through Oakfield (the GOES-8 imager instrument was actually scanning the Oakfield area at 2348 UTC).

GOES-8 Infrared images [click to play animation | MP4]

On a larger-scale view of GOES-8 Water Vapor images (below), a sharp gradient of warm-to-cool brightness temperature — orange/yellow to blue enhancement, portraying the gradient of dry air to moist air — highlighted the presence of a middle-tropospheric jet streak that was moving southeastward across the state.

GOES-8 Water Vapor images [click to play animation | MP4]

Examples of Derived Product Images from the GOES-8 Sounder can be seen here.

Posted in GOES sounder, GOES-8, Historical, Severe convection | No Comments »

Severe weather in the central Plains

June 19th, 2021 | Scott Bachmeier

GOES-16 “Red” Visible (0.64 µm) images, with SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched plots of SPC Storm Reports — and showed severe thunderstorms across eastern Colorado, western Kansas and far southwestern Nebraska late in the day on 19 June 2021. Numerous pulsing overshooting tops were evident with many of these storms. Wind gusts to 88 mph were reported in Kansas

The corresponding 1-minute GOES-16 “Clean” Infrared Window (10.35 µm) images (below) displayed cloud-top infrared brightness temperatures as cold as -75 to -79ºC (brighter white pixels within dark black clusters) with some of the more robust overshooting tops.

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play animation | MP4]

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Severe weather associated with the landfall of Tropical Storm Claudette

June 19th, 2021 | Scott Bachmeier

GOES-16 “Red” Visible (0.64 µm) images, with SPC Storm Reports plotted in red [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched plots of SPC Storm Reports — and showed severe thunderstorms associated with the landfall of Tropical Storm Claudette (surface analyses) early in the day on 19 June 2021. Numerous pulsing overshooting tops were evident with some of these storms.

The corresponding 1-minute GOES-16 “Clean” Infrared Window (10.35 µm) images (below) displayed cloud-top infrared brightness temperatures as cold as -80ºC (violet pixels) with some of the more robust overshooting tops. On both the Visible and Infrared images, Butler County, Alabama is outlined in blue — with Interstate Highways plotted in violet. A multi-vehicle accident with 10 fatalities occurred along Interstate 65 in far northeastern Butler County around 1830 UTC (2:30 PM local time); although no severe weather was reported in Butler County, the Infrared images showed cold cloud-top brightness temperatures moving northeastward over that area during much of the morning hours, so heavy rainfall and wet roads (with some residual areas of ponding water) may have been a contributing factor to this accident. Greenville in Butler County received 1.71 inches of rainfall — but not far to the southwest, Evergreen in Conecuh County received 3.16 inches of rainfall during the landfall of Claudette.