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).

VIIRS views volcanic activity at Nishinoshima in the western Pacific

April 27th, 2020 |

NOAA-20 VIIRS Day Night Band Visible (0.70 µm) imagery,  1603 UTC 19 April 2020, Click to enlarge)

Nishinoshima is a small volcanic island (at 27.2471° N, 140.8779° E) about 150 km west of Chichijima.)  Nishinoshima has grown in size over the past decades because of volcanic activity, including activity (apparently accompanied by occasional earthquakes) that started in March 2020.   Day Night Band imagery from NOAA-20, above, (toggled with an annotated image) shows the light from the ongoing volcanic activity on 19 April 2020 (Clean Window Infrared imagery also showed a heat source).  (Day Night Band imagery is also available here, from NASA Worldview)

Many thanks to Brandon Aydlett, WFO Guam, for the imagery.


The toggle below (imagery courtesy William Straka, CIMSS), shows more NOAA-20 VIIRS data from the same NOAA-20 pass:  Day Night Band Imagery, 3.75 µm Shortwave Infrared imagery (Band I04), 1.61 µm near-infrared imagery (Band M10) and 2.26 µm (Band M11)4.05 µm Shortwave Imagery (Band M13), and the VIIRS Active Fire Product.  All show evidence of the hot spot over the volcano.

NOAA-20 VIIRS Imagery at 1607 UTC on 19 April 2020: Day Night Band (0.7 µm) Visible Imagery, I04 Band (3.75 µm Shortwave Infrared), M10 Band (1.61 µm Near Infrared), M11 Band (2.25 µm Near-Infrared), M13 Band (4.05 µm Shortwave Infrared) and the VIIRS Active Fire Product (Click to enlarge)