30-second GOES-17 imagery of severe thunderstorms over Idaho

April 30th, 2020 |

GOES-17 “Red” Visible (0.64 µm) images, with time-matched SPC Storm Reports plotted in red [click to play animation | MP4]

GOES-17 “Red” Visible (0.64 µm) images, with time-matched SPC Storm Reports plotted in red [click to play animation | MP4]

Overlapping 1-minute Mesoscale Domain Sectors provided GOES-17 (GOES-West) “Red” Visible (0.64 µm) images at 30-second intervals (above) — which showed thunderstorms that produced large hail and damaging winds across parts of southern Idaho (SPC Storm Reports) on 30 April 2020.

To the south, strong winds at the surface were lofting plumes of blowing dust from Carson Sink in western Nevada and from the Martin Fire burn scar in northern Nevada — GOES-17 Dust Red-Green-Blue (RGB) images (below) displayed these dust plumes as brighter shades of pink. The Carson Sink plume eventually moved across Interstate 80 in north-central Nevada, while the fire burn scar plume eventually moved over Interstate 84 in southern Idaho.

GOES-17 Dust RGB images [click to play animation | MP4]

GOES-17 Dust RGB images [click to play animation | MP4]

Ice off the coast of Greenland

April 30th, 2020 |

GOES-16 True Color RGB images [click to play animation | MP4]

GOES-16 True Color RGB images [click to play animation | MP4]

GOES-16 (GOES-East) True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) showed sea ice features off the southeast coast of Greenland on 30 April 2020. The ice structures were deformed by northerly winds behind a weak disturbance that was moving southward farther offshore.

Thanks to Antonio Vecoli for alerting us to thee interesting ice formations.

30-second GOES-16 imagery of rapidly-developing severe thunderstorms over the Midwest

April 28th, 2020 |

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 time-matched SPC Storm Reports plotted in red [click to play animation | MP4]

Overlapping 1-minute Mesoscale Domain Sectors provided GOES-16 (GOES-East) “Red” Visible (0.64 µm) images at 30-second intervals (above) — which showed rapidly-developing thunderstorms over northeastern Oklahoma, southeastern Kansas and southwestern Missouri on 28 April 2020. These storms developed along and ahead of an approaching cold front, and produced large hail and damaging winds (SPC Storm Reports).

The corresponding 30-second GOES-16 “Clean” Infrared Window (10.35 µm) images are shown below.

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

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

NOAA-20 Gridded NUCAPS fields of Most-Unstable CAPE at 1927 UTC (below) indicated that an axis of high instability existed along the Kansas/Missouri border shortly preceding convective initiation.

VIIRS Visible image with available NUCAPS soundings + Gridded NUCAPS Most-Unstable CAPE [click to enlarge]

NOAA-20 VIIRS Visible (0.64 µm) image with available NUCAPS sounding points + Gridded NUCAPS Most-Unstable CAPE [click to enlarge]

NUCAPS profile for the green point located in far eastern Kansas [click to enlarge]

NUCAPS profile for the green sounding point located in far eastern Kansas [click to enlarge]

Within that axis of instability along the Kansas/Missouri border, the NUCAPS profile for the green (using both Infrared and Microwave retrievals) sounding point in far eastern Kansas (located northeast of Chanute, station identifier KCNU) is shown above —  for the Most Unstable air parcel, calculated CAPE was 3714 J/kg, with a Lifted Index of -12ºC.

Farther to the south, the NUCAPS profile for the yellow (using only Microwave retrievals) sounding point (located east-southeast of KCNU) is shown below — for the Most Unstable air parcel, calculated CAPE was 3714 J/kg, with a Lifted Index of -14ºC.

NUCAPS profile for the yellow sounding point located in far eastern Kansas [click to enlarge]

NUCAPS profile for the yellow sounding point located in far eastern Kansas [click to enlarge]

The closest rawinsonde report (in terms of time and distance) was from Springfield in southwestern Missouri at 18 UTC (below) — it indicated Most Unstable CAPE and Lifted Index values of 3060 J/kg and -6ºC, respectively. The later availability of NUCAPS soundings closer to the region of convective initiation revealed the rapid atmospheric destabilization that allowed for explosive development of the severe thunderstorms as seen on GOES-16 imagery.

Plot of 18 UTC rawinsonde data from Springfield, Missouri [click to enlarge]

Plot of 18 UTC rawinsonde data from Springfield, Missouri [click to enlarge]

Damaging winds from a severe thunderstorm in Texas

April 27th, 2020 |

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]

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 an isolated large thunderstorm moving east-southeastward across the Mexico/Texas border region during the early evening hours on 27 April 2020. Concentric storm-top gravity waves could be seen propagating radially outward from the storm center (for example, at 0211 UTC) — and pulsing overshooting tops were evident, with the coldest cloud-top infrared brightness temperature of -77.5ºC  occurring at 0128 UTC.

After about 0030 UTC, the GLM Flash Extent Density (FED) began to increase with this storm — in fact, the FED just northwest of Del Rio International Airport (KDRT) rapidly rose from 122 flashes per 5 minutes at 0119 UTC to 189 flashes per 5 minutes at 0139 UTC. During the period of this lightning jump, damaging winds — including a wind gust of 77 mph at KDRT at 0135 UTC — occurred in the Del Rio area (SPC Storm Reports).