Severe weather in the central Plains

June 19th, 2021 |

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

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]

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

Tropical Storm Claudette makes landfall along the central Gulf Coast

June 19th, 2021 |

MIMIC Total Precipitable Water (TPW) estimates, 1900 UTC 18 June 2021 – 1800 UTC 19 June 2021 (Click to enlarge)

The Potential Tropical Cyclone that has been moving northward through the Gulf of Mexico made landfall southwest of New Orleans, LA on Saturday 19 June as a minimal Tropical Cyclone. The animation of total precipitable water, above, from the MIMIC TPW website, shows that most of the storm’s moisture is east of the center. (The circulation of Pacific Tropical Storm Dolores is also apparent, making landfall near Punta San Telmo in Mexico) A percent-of-Normal plots from NOAA/NESDIS/OSPO, below, shows values about 150% of normal over much of the southeast USA. Consequently, Flash Flood Watches are in effect over much of southern Alabama northeastward into western North Carolina, as shown below.

Percent-of-normal Blended Total Precipitable Water, 1800 UTC on 19 June 2021 (Click to enlarge)

Weather hazards at 1911 UTC on 19 June 2021 (Click to enlarge)

A True-Color image from CSPP Geosphere, below, taken from this link, shows the storm inland over southwestern Alabama; much of the rain and deep moisture with the storm remains to the east of the center.

True-Color imagery, 1921 UTC on 19 June 2021, from CSPP Geosphere (Click to enlarge)


24-hour precipitation ending 1200 UTC on 20 June 2021 (Click to enlarge)

24-hour precipitation totals (from this site) are shown above. The analysis shows a few spots in northern Alabama received 6-8″ of rain.

CMORPH2 estimates for the 24-hours of precipitation ending at 0000 UTC on 20 June (that is, 12 hours before the estimate above), from RealEarth, are shown below.

24-hour CMORPH2 precipitation total estimates for the time ending 0000 UTC on 20 June 2021 (Click to enlarge)

GSMaP (link) also shows satellite-derived precipitation estimates. The 24-hour estimate ending at 0000 UTC on 20 June is shown below.

GSMaP precipitation estimate for the 24 hours ending 0000 UTC on 20 June 2021 (Click to enlarge)

Severe weather associated with the landfall of Tropical Storm Claudette

June 19th, 2021 |

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

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.

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

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

Additional details regarding Claudette’s abundant tropical moisture and resulting heavy rainfall can be found on this blog post.