GOES-18 (GOES-West) Nighttime Microphysics RGB and daytime True Color RGB images from the CSPP GeoSphere site (above) displayed the cyclonic circulation of an actinoform cloud feature as it moved westward toward Hawai`i on 03 July 2023.

A closer view using GOES-18 “Red” Visible (0.64 µm) and Day Cloud Phase Distinction RGB images (below) showed the actinoform cloud as it approached the island of Oahu. 15-minute METAR surface reports revealed that one of the actinoform’s “spiral bands” produced brief (20-30 minute) periods of light rain and/or drizzle — first at Kaneohe Bay (PHNG) beginning around 0201 UTC, and then at Wheeler Air Force Base (PHHI) beginning around 0331 UTC — as it passed over the island.

According to the Day Cloud Phase Distinction RGB Quick Guide, shades of green generally denote cloud tops that are beginning to glaciate — but in this case, a GOES-18 Day Cloud Phase Distinction RGB image at 2301 UTC (below) included cursor-sampled values of RGB components along with the corresponding Cloud Top Phase and Cloud Top Height derived products at that same location. Since cloud-top 10.3 µm infrared brightness temperatures at that cursor location were quite warm (15.27ºC), derived products indicated that the Cloud Top Phase was Water (as opposed to a Mixed water/ice phase, which is often associated with cloud features exhibiting similar shades of green in this particular RGB).

AWIPS Users: a variety of GOES RGB types combined with Derived Product Readouts is available under the Satellite -> Local Menu Items menu (below).

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GOES-16 (GOES-East) Near-Infrared “Vegetation” (0.86 µm), Vegetation Channel Difference (0.64 µm – 0.86 µm), Day Land Cloud RGB and CIMSS Natural Color RGB images (above) showed a west-to-east oriented damage swath across Furnas and Harlan counties in far southern Nebraska n 02 July 2023  — which resulted from wind-driven large hail (wind gusts to 70 mph, hail up to 3.00 inches in diameter: Local Storm Reports) 3 days earlier during the 28-29 June Derecho event.

GOES-16 Rayleigh-scattering-corrected True Color RGB images from the CSPP GeoSphere site (below) provided a higher-contrast view of the damage swath, which exhibited shades of tan (in contrast to the predominantly greener appearance of adjacent healthy vegetation and fields of crops).

The derecho damage swath also showed up well in a toggle between Suomi-NPP VIIRS True Color RGB and False Color RGB images valid at 1932 UTC (below). Data used to create the VIIRS images were downloaded and processed by the SSEC/CIMSS Direct Broadcast ground station.

1-minute Mesoscale Domain Sector GOES-16 “Clean” Infrared Window (10.3 µm) images just after local midnight on 29 June (below) inc\luded time-matched (+/- 3 minutes) SPC Storm Reports plotted in white — which showed the reports of wind/hail responsible for the Furnas/Harlan county damage swath seen on 02 July.

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1-minute Mesoscale Domain Sector GOES-18 (GOES-West) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.3 µm) images (above) showed Category 1 Hurricane Beatriz just off the west coast of Mexico (near Ixtapa, station identifier MMZH) as a cloud-filled eye was becoming more apparent.

A DMSP-17 Microwave (85 GHz) image at 1322 UTC (below) from the CIMSS Tropical Cyclones site indicated that the eyewall had not yet completely closed at that time.

However, Synthetic Aperture Radar (SAR) winds (below) from an earlier 1240 UTC overpass of RCM-2 (source) did suggest that a closed eye had formed — and the peak radial wind speed at that time was 79 knots.

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A long-lived mesoscale convective system (MCS) accompanied by strong winds at its leading edge, i.e., a Derecho, moved through the central US on 29 June 2023. The animation above shows GOES-16 Clean Window Infrared (10.3 µm) imagery at 15-minute intervals from 0100 UTC through 19 UTC on 29 June 2023. The imagery also includes 5-minute accumulations of Flash Extend Density from the Geostationary Lightning Mapper (GLM), and GOES-derived Lifted Indices. Of particular note is the corridor of instability over northern Kansas/southern Nebraska, and the large pool of instability of Illinois, that helped sustain the thunderstorms within the MCS as the feature propagated eastward. The system started as a supercell with a pronounced enhanced V as well (shown below) before evolving into an MCS overnight. Numerous reports of severe weather occurred on both 28 June and 29 June, as shown below.

The high winds caused blow-over in some cornfields in central Illinois (near Farmer City in DeWitt County) to the west of Champaign-Urbana, as shown in this tweet from Andrew Pritchard. He also showed damage in Farmer City.

1-minute Mesoscale Domain Sector GOES-16 “Clean” Infrared Window (10.3 µm) images around the beginning period (above) and the end period of the derecho event (below) include time-matched plots of Local Storm Reports. The earlier thunderstorms produced a few tornadoes in Nebraska/Colorado, hail as large as 4.00 inches in diameter in Wyoming/Colorado and wind gusts exceeding 80 mph in Colorado — while the later thunderstorms exhibited an impressive display of overshooting tops across Illinois (having cloud-top infrared brightness temperatures in the -80 to -86ºC range, shades of white embedded within darker black areas) as the MCS produced several wind gusts of 80 mph and higher. 

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The storm that grew into this MCS had both an Enchanced-V structure, the accompanying warm trench, and an obvious Above-Anvil Cirrus Plume, all hallmarks of severity, as shown in the toggle below.

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Note that a corridor of instability remains along the Kansas/Nebraska border at the end of the animation up top, and as shown below. Convection is forming over the high plains of Colorado. Will convection follow a similar path on the 29th into the 30th?

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