A toggle between Suomi-NPP VIIRS Visible (0.64 µm) and Infrared Window (11.45 µm) images valid at 1335 UTC on 27 June 2024 (above) showed a severe-warned thunderstorm just west of Noatak, Alaska. This thunderstorm — located north of the Arctic Circle — exhibited a cloud-top infrared brightness temperature as cold as -52.69ºC.

1-minute Mesoscale Domain Sector GOES-18 (GOES-West) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (below) showed the thunderstorm activity as it moved northwest past the Noatak (PAWN) area and continued to approach the coast.

A cursor sample of GOES-18 Infrared (10.3 µm) cloud-top brightness temperature along with the corresponding Cloud Top Height and Cloud Top Temperature derived products at 1418 UTC on 27 June (below) depicted values of -42.13ºC, 25627.90 ft and -44.59ºC, respectively.

For a cloud top height of 30000 ft, the GOES-18 parallax correction near Noatak would be 58-60 km (36-37 mi) to the south-southeast (below).

Examining a plot of rawinsonde data from Kotzebue, Alaska (PAOT) at 1200 UTC on 27 June (below), the GOES-18 cloud-top infrared brightness temperature of -42.13ºC was near the altitude of the Most Unstable air parcel’s Equilibrium Level (EL) at 28984 ft or 8.8 km — while the -52.69ºC sensed by Suomi-NPP suggested an EL overshoot of about 1 km.

The Severe Thunderstorm Warnings this morning in northwest Alaska were the westernmost AND the northernmost that that the NWS has ever issued. Note: the Google Earth perspective makes the SW Alaska ones appear farther west, but they are not. [polygons from Iowa State Mesonet] pic.twitter.com/YmhZnb8hh1

— Brian Brettschneider (@Climatologist49) June 27, 2024

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Author’s note: given that I’m retiring at the end of the day, this likely represents my last blog post. When I started the CIMSS Satellite Blog back in August 2006, it was really meant to slowly build myself a library of cases from which I could easily borrow imagery to use in developing VISIT and SHyMet distance learning modules. As it grew in size and scope, I was quite surprised how popular the blog became, both on a national and an international level. Over time, more CIMSS authors joined in (which helped to diversify the blog content). The many comments that we received from our blog readers (which often included NWS forecasters and people from academia) always led to fruitful dialogue, and some great blog posts.

Fast-forward 18 years to 2024, and after growing to over 4000 posts, I feel quite satisfied with what the CIMSS Satellite Blog has become. Our readers learn from it, and we’ve received countless requests for permission to use blog post images/animations (which we happily grant). Hopefully this blog even helps to spark the imagination of future meteorologists-to-be (just like the glossy paper copy of a satellite image did for me, received while attending an open house at the NWS forecast office in Sioux Falls SD, at the impressionable age of 13).

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) images from all 16 of the ABI spectral bands along with a Rocket Plume RGB (above) displayed signatures of the SpaceX Falcon Heavy rocket booster that launched GOES-U from NASA Kennedy Space Center in Florida at 2126 UTC (5:26 PM EST) on 25 June 2024. A warm thermal signature of the rocket booster (moving rapidly to the east-northeast) and/or the relatively bright in bands 01-06 or cold in bands 07-16 rocket condensation cloud (which remained just off the coast, due to wind shear with height) were evident in all 16 of the ABI spectral band images, as well as the Rocket Plume RGB imagery. One of the more notable rocket signatures was seen in imagery at 2129 UTC: the very warm thermal anomaly of the boostback burn of the two Stage 1 side boosters, along with the warm thermal anomaly of the Stage 2 engine start (located farther downrange).

30-second images from GOES-18 (GOES-West) are shown below.

1-minute GOES-16 Visible/Infrared Sandwich RGB images with/without an overlay of GLM Flash Extent Density (below) showed the cold overshooting tops and lightning activity associated with a small cluster of thunderstorms that was moving eastward toward the coast — at the 2126 UTC launch time, the edge of a thunderstorm anvil (and its associated lightning) was about 20 miles southwest of Launch Complex 39A at Kennedy Space Center (where the Falcon Heavy condensation cloud originated).

Note that the Falcon Heavy condensation cloud became sheared, and eventually began drifting back toward the coast — a plot of rawinsonde data (source) from Cocoa Beach KXMR (below) depicted the shift to northeasterly winds at the 100 hPa pressure level (an altitude of about 17-18 km).

Re-entry

The GOES ABI was able to glimpse the booster rockets re-entry as well, from both GOES-East and -West meso-scale sectors.

The same loop as above, minus the red and white circles. These loops were created by T. Schmit, NOAA/NEDIS/STAR.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) showed thunderstorms that produced 7 tornadoes, hail as large as 2.00 inch in diameter and damaging wind gusts across southern Wisconsin (SPC Storm Reports) on 22 June 2024. The Infrared images revealed pulses of thunderstorm overshooting tops that exhibited 10.3 µm brightness temperatures as cold as -75ºC (brighter white pixels embedded within dark black regions) — and brief Enhanced-V cloud-top signatures were evident with some of the storms. A few short-lived Above-Anvil Cirrus Plumes (reference | VISIT training) could be seen in the Visible images (although there was no corresponding distinct AACP signature in the lower-resolution Infrared images).

1-minute GOES-16 Visible and Infrared images with an overlay of GLM Flash Extent Density (below) showed the lightning activity associated with these thunderstorms, which included a few brief lightning jumps.

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Geosphere true-color imagery over the Atlantic Ocean to the east of Florida and Georgia, above, shows a low-level cyclonic circulation with strong convection to its south. The appearance of the system suggests strong shear; an analysis of shear from the SSEC Tropical Weather website, below, shows the northerly shear over the storm that displaces the convection.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed a closer view of the exposed low level circulation center (LLCC) of Invest 92L. A slight amount of trochoidal motion (wobble) was seen as the LLCC moved toward the coast.

1-minute GOES-16 Visible images with plots of 5-minute Derived Motion Winds (below) depicted slightly higher wind speeds (30-35 knots, yellow wind barbs) within the northeast quadrant of 92L — but satellite-derived wind speeds with the circulation of 92L were generally in the 10-25 knot range. Invest 92L passed between Buoy 41008 to the north and Buoy SAUF1 to the south; on 21 June the highest wind speeds/gusts at those two buoys were in the 22-29 knot range. 92L eventually moved inland several hours after sunset, near the Georgia/Florida border — between Brunswick GA (KSSI) and Jacksonville FL (KCRG). Wind speeds/gusts remained below 30 knots at those two sites as well.

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GOES-16 Geocolor imagery, overlain with GLM Flash Extent Density fields, below, (from this source), show meager lightning within the convection to the south of the low-level cyclonic circulation.

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More information on this system is available at the National Hurricane Center, and from the NWS Forecast Offices in Jacksonville FL and in Charleston SC.

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