A toggle between NOAA-20 (mislabeled as NPP) VIIRS Day/Night Band (0.7 µm) and Infrared Window (11.45 µm) images valid at 0612 UTC on 28 August 2023 (above) showed Hurricane Franklin a few hours before it reached Category 3 intensity.

Franklin rapidly intensified to Category 4 intensity as of 1200 UTC — animations of GOES-16 (GOES-East) “Red” Visible (0.64 µm) images, with/without an overlay of GLM Flash Extent Density (above) and “Clean” Infrared Window (10.3 µm) images (below) showed the hurricane as it moved away from Buoy 41047 during the 1201-1701 UTC period. Abundant lightning activity was seen within the eyewall region — and mesovortices were evident within the eye.

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Tropical Storm Idalia has formed in the northwestern Caribbean Sea, in between Cuba and Mexico. The True-Color mp4 animation above, taken from CSPP Geosphere site (direct link to the animation), shows active convection over the Caribbean that is coalescing around the low-level circulation center (located near 20^oN, 85.5^oW at 2100 UTC on 27 August)

A still image from 2236 UTC on 27 August, below, shows GOES-16 Band 13 “Clean Window” infrared (10.3 µm) imagery overlain on top of the derived SSTs from 2200 UTC. Very warm water — upper 80s to low 90s degrees Fahrenheit — is diagnosed along Idalia’s forecast path in the eastern Gulf of Mexico. Band 13 Brightness Temperatures are very cold: near -80^oC.

Microwave imagery from the CIMSS Tropical Website, below, show that Idalia in the afternoon of 27 August 2023 was not a poorly-organized lopsided storm. Much of the deepest convection was south of the center (as might also be inferred from the asymmetric distribution of cold cloud tops around the center in the infrared imagery above).

The toggle below shows the forecast path of Idalia into the northwestern Gulf of Mexico along with plots of Oceanic Heat Content — a measure of how deep the warm waters are — and atmospheric shear. Idalia is forecast to traverse very warm waters as shown in the SST plot above. The narrow Loop Current in the Gulf of Mexico is where the warm surface waters are least likely to be cooled by storm-induced mixing. In addition, the shear fields show Idalia moving into a less favorable shear environment. Strengthening is expected.

Note that Idalia’s position allows imagery from the CIMSS Direct Broadcast site to show information, for example channel 18 (183 GHz from NOAA-21), or VIIRS True Color from Suomi NPP (an image that includes both Idalia and Hurricane Franklin over the Atlantic Ocean). Direct Broadcast imagery for Idalia is also available from AOML.

Interests along the northeastern Gulf Coast and in the southeastern United States should pay close attention to Idalia’s path. Refer to the National Hurricane Center for the latest information on Idalia.

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Overlapping 1-minute Mesoscale Domain Sectors provided GOES-16 (GOES-East) images at 30-second intervals from all 16 of the ABI spectral bands (above), which displayed the northeast-moving bright reflectance and/or the warm thermal signature of a SpaceX Falcon 9 rocket booster as the Crew-7 Mission was launched from Cape Canaveral Space Force Station in Florida at 0727 UTC (3:27 AM EST) on 26 August 2023. The low-altitude rocket launch condensation cloud was also evident in imagery from the Infrared bands (07-16), located just offshore from the launch site. One or both of these rocket launch signatures were unambiguously detected by 15 of 16 of the ABI spectral bands (02-16), as well as Rocket Plume RGB images. A notable feature was the signature of the Stage 1 “Boostback Burn” — where the expansion/cooling of the rocket engine’s gas plume was apparent in the Band 08 image at 0730 UTC.  Note: the default enhancements of the Visible bands (01 and 02) and Near-Infrared bands (03-06) were modified, to help better visualize the nighttime rocket signature.

A 16-panel display of GOES-16 ABI spectral bands at 0728 UTC (below) showed the rocket signature in bands 02-16 at that time.

In fact, a very subtle reflectance signature was also apparent in ABI spectral band 01 immediately after launch at 0727 UTC — it was partially masked by the map overlay, which was removed for the 0726-0727 UTC comparison seen below.

A zoomed-in view using a stepped sequence of GOES-16 images from 16 ABI spectral bands 03, 05, 06 and 07 (below) showed the brighter/warmer signature of the Falcon 9 rocket Stage 1 Landing Burn at 0734 UTC, as it successfully returned to the Cape Canaveral Space Force Station.

A GOES-18 (GOES-West) Mesoscale Domain Sector was also positioned over the region, providing 1-minute images from a more oblique perspective (below).

A 16-panel display of GOES-18 ABI spectral bands at 0728 UTC (below) showed that rocket signature was evident in bands 02-16 (as was the case with GOES-16).

Thanks to Todd Beltracci, The Aerospace Corporation, for his insightful discussion on several aspects of this imagery.

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Direct Broadcast antennae give timely full-resolution imagery from various Low-Earth-Orbit satellites as they move within the view of the satellite received. Community Satellite Processing Package (CSPP) software takes the downloaded signal and produces imagery (or AWIPS-ready files). The toggle above shows VIIRS (Visible-Infrared Imaging Scanning Radiometer) and ATMS (Advanced Technology Microwave Sounder) data from NOAA-20 from a Guam overpass near 0300 on 25 August 2023. A benefit of having visible/infrared and microwave instruments on the same orbiting platform is that it’s easier to compare (directly) features in the two images. In this case, note how the brightest (whitest) features in VIIRS channel M15 (10.8 µm) are very cold in the 88 GHz, and have large rain-rates.

Data from direct broadcast also allows a user to compare microwave data from two different satellites. NOAA-20 and GCOM-W1 both carry microwave sounders (the Advanced Microwave Scanning Radiometer — ASMR-2 — in GCOM-W1) that sense energy at similar frequencies. The toggle below compares ATMS data at 88 GHz and AMSR-2 data at 89.2 GHz from about the same time. Note the significantly better resolution from AMSR-2!

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Thanks to Doug Schumacher, SSEC/CIMSS, for supplying these images!

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