CSPP Geosphere imagery above (direct link) shows an area of sun glint over the tropical Atlantic. Embedded within the brighter areas of sun glint is a dark path centered near 7^oN, 52^oW over the ocean to the northeast of French Guiana. Long-time readers of this blog will no doubt recognize this feature as an area with very light winds (link). Indeed, Advanced Scatterometer (ASCAT) winds from MetopC (source), below, from 0121 UTC on 28 June, show light winds in the vicinity.

---

Your eye might also be drawn to the circulation in the animation above that is the current invest 95L in the tropical Atlantic. In what kind of environment is that system developing? What satellite data can be used to describe this system? The Saharan Air Layer analysis, below (source), shows the storm south of an extensive SAL region. A water vapor image (sensing the mid-troposphere) at 1200 UTC (link) also shows extensive dry air surrounding the system.

MIMIC Total Precipitable Water analyses (source) for the 24 hours ending at 1400 UTC on 28 June 2024, below, shows the cyclonic circulation associated with the Invest as it moves across 40^oW longitude (another concentrated area of moisture is moving through the northwestern Caribbean Sea).

MetopC ASCAT winds, below, show a circulation near 9^oN/38^oW at 2334 UTC on 27 June 2024.

Wind shear and Sea Surface Temperature (SST) analyses surrounding 95L, below, show a favorable environment (that is, low values of wind shear, and warm SST values). Imagery below is from the SSEC Tropical Website.

GeoColor imagery overlain with GLM observations, below (source), show occasional GLM lightning strikes within the convective cluster surrounding the tropical invest.

---

For more information on this system, refer to the National Hurricane Center and CIMSS Tropical Weather websites.

View only this post Read Less

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 (above) 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.

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) — 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

___________________________

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).

View only this post Read Less

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).

View only this post Read Less

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.

View only this post Read Less