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).

8:08p 4/27/2020 – This storm in South Central Val Verde County is producing a ton of lightning. The NLDN reported a total of over 700 strikes out of the storm. A few of these lightning strikes have occurred well out ahead of the storm with one or two within 10 miles of Del Rio.

— NWS Austin/San Antonio (@NWSSanAntonio) April 28, 2020

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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.

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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.

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GOES-16 (GOES- East) “Clean” Infrared Window (10.35 µm) images, with and without plots of GLM Groups (above) showed a Mesoscale Convective System (MCS) that was propagating southward across eastern Mexico (in advance of an approaching cold front) from 2001 UTC on 25 April to 1501 UTC on 26 April 2020. The coldest cloud-top infrared brightness temperatures were -90ºC (yellow pixels embedded within dark purple regions). This MCS was prolific lightning-producer — which included numerous anvil streamers that extended well east and northeast of the main convective core (below).

A toggle between NOAA-20 VIIRS Infrared Window (11.45 µm) and Day/Night Band (0.7 µm) images at 0841 UTC (below) also revealed isolated pixels in the overshooting top region with brightness temperatures of -90ºC (yellow enhancement) — along with numerous bright lightning streaks in the Day/Night Band image, located well east of the convective core (consistent with the GOES–16 GLM imagery). At that time, the core of the MCS was located just off the coast of Mexico, between Poza Rica (MMPA) and Veracruz (MMVR).

Plots of rawinsonde data from Veracruz, Mexico (below) showed that the coldest tropopause temperatures were -78.1ºC at a pressure level of 103 hPa — so the coldest GOES-16 and NOAA-20 infrared brightness temperatures of -90ºC indicated overshooting tops extending well about the tropopause.

On 25 April, GOES-16 True Color Red-Green-Blue (RGB) images created using Geo2Grid (below) portrayed a well-defined rope cloud with an undular bore along the cold frontal boundary. Also evident was widespread dense smoke across much of the Gulf of Mexico, a result of prolonged fire activity in the Yucatan Peninsula of Mexico and parts of Central America.

So after breaking the #lightning archive tool a few times (because of searching a time period with too much lightning)…I’ve counted up the dots between 2000 UTC 25 April and 1500 UTC 26 April. 1.1 million! https://t.co/yQrmbONPQ0 pic.twitter.com/K0eedrOAdC

— Ch?is Vagas|?y (@COweatherman) April 26, 2020

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GOES-16 (GOES-East) True Color Red-Green-Blue (RGB) images created using Geo2Grid (above) revealed the large, dark smoke plume resulting from a fire — likely at the Muelle Bachaquero Oil & Natural Gas Company (Google maps) — along the eastern shore of Lake Maracaibo in far northwestern Venezuela on 25 April 2020. Other features apparent in the imagery were persistent pyrocumulus clouds over the fire source, and the bright appearance of solar reflection off surface oil slicks caught within a counterclockwise gyre in the middle of the lake (similar solar reflection was seen off the Deepwater Horizon oil slick, as documented here and here).

VIIRS True Color RGB images from Suomi NPP and NOAA-20 as viewed using RealEarth (below) indicated that the leading edge of the dark smoke plume had drifted westward across the Venezuela/Colombia border after 18 UTC.

GOES-16 Shortwave Infrared (3.9 µm) images (below) showed the thermal anomaly or fire “hot spot” (small cluster of dark black pixels), which first appeared at 1100 UTC.

Black smoke from a refinery fire on Lake Maracaibo.

Seen by GOES-East on Saturday (4-25): https://t.co/QMXKD3VVar. pic.twitter.com/nVcIIHaqCr

— CIRA (@CIRA_CSU) April 29, 2020

Dense and large #smoke cloud from (probably) oil industry related fire, pretty images but none of the operational aerosol retrievals (MODIS,VIIRS, GOES) picked up this event. UV sensors (#OMPS, OMI, #Tropomi) fared better but no aerosol OD retrievals.(h/t @GOESguy) pic.twitter.com/mtqfGVWLM9

— Santiago Gassó (@SanGasso) April 29, 2020

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