A 30-meter resolution Landsat-8 False Color image viewed using RealEarth (above) displayed thin filaments of ice (brighter shades of cyan) in far western Lake Superior, just off the northern coast of Wisconsin, on 27 April 2022. Chequamegon Bay in northern Wisconsin also had significant amounts of ice remaining from the winter months. Remnant snow cover (muted shades of cyan) was also apparent across much of northeastern Minnesota and parts of northern Wisconsin.

During the preceding overnight hours, a NOAA-20 VIIRS Advanced Clear-Sky Processing for Ocean (ACSPO) Sea Surface Temperature image around 0831 UTC (below) indicated that SST values were generally around 34^oF (darker blue enhancement) in the portion of the lake north of the ice filaments. Farther to the east, the West Superior Buoy 45006 was reporting a SST value of 33^oF at that time.

GOES-16 (GOES-East) True Color RGB images displayed using CSPP GeoSphere (below) showed that (1) the thin ice filaments just off the coast of Wisconsin were moving southwestward during the day, and (2) within Chequamegon Bay, significant ice fracturing began during the afternoon hours.

This ice filament motion and ice fracturing was the result of persistent northeasterly surface winds during the day, which gusted to 29 knots at Duluth Sky Harbor Airport (below).

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The above image (from here; other flood product are available here) shows inundation occurring around the Red River of the North on the North Dakota/Minnesota border. The image combines the excellent spatial resolution of VIIRS on NOAA-20/Suomi-NPP with the excellent temporal resolution of the GOES-16 ABI) Precipitation over the past 7 days ending at 1200 UTC, below, from this site, shows an axis of heavy (>4″!) precipitation just south of Grand Forks. Flood gauges on 27 April (here, from “River Observations” at this site), show major flooding occurring over eastern North Dakota.

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The toggle below compares Band 2 and Band 5 (and the Day Land Cloud RGB) on 27 April 2022 at 1646 UTC. The 1.61 µm imagery has a very dark signal over the flooded region between Oslo and Drayton — because water absorbs energy at that wavelength (that is, it doesn’t reflect much back to the satellite) — so there is excellent contrast between land and water. Snow (and cirrus clouds) also absorb energy with a wavelength of 1.61 µm, so the reflectance differences between visible/0.64 µm (very bright) and the 1.61 µm (darker) can be used to identify regions of snow on the ground (for example between McClusky and Karlsruhe at the western edge of the image; between Langdon and Petersburg over the central part of the image); features that are bright in both the 0.64 µm and 1.61 µm imagery (for example, the feature stretching east-southeastward from between McClusky and Harvey to near Pingree) are clouds. Any RGB that includes both the 1.61 µm and the 0.64 µm (or 0.87 µm) imagery will highlight snow on the ground. The Day Land Cloud, shown in the toggle below, shows cyan in regions of snow (or cirrus).

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The series of webcam images below, spanning 21-27 April (with no 23 April image), from this website, shows the changes in the river at the Sorlie Bridge in East Grand Forks.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) images from all 16 ABI spectral bands (above) displayed thermal signatures of the SpaceX Falcon-9 rocket booster as the Crew-4 Mission was launched from Cape Canaveral Space Force Station in Florida on 27 April 2022. The low-altitude rocket condensation cloud was also evident, moving slowly eastward away from the launch site.

GOES-16 Plume RGB images created using Geo2Grid (below) provided an integrated view that highlighted both the northeast-moving hot thermal signature of the rocket booster, and the low-altitude rocket condensation cloud that drifted eastward.

A toggle between Upper-level Water Vapor (6.2 µm) images from GOES-16 (GOES-East) and GOES-17 (GOES-West) at 0755 UTC (below) showed a large eastward displacement of the booster rocket’s thermal signature in the GOES-17 image — due to parallax associated with the very large viewing angle from GOES-17.

A 16-panel display of all GOES-16 ABI spectral bands at 0753 UTC which includes AWIPS cursor sampling values (above) indicated that a slight reflectance value (1.75%) was detected for Band 2 (“Red” Visible, 0.64 µm) — but not for Band 1 (“Blue” Visible, 0.47 µm). However, with GOES-17 viewing the rear portion of the northeastward-ascending Falcon 9 rocket booster, a slight reflectance signal (0.13%) was also seen with the 0.47 µm spectral band (below).

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) images (above) showed the thermal signatures of numerous prescribed burns across the Flint Hills of eastern Kansas on 26 April 2022. Although the majority of the fires burned only briefly, some exhibited very rapid increases in their 3.9 µm infrared brightness temperature — for example, the hottest fire went from 30^oC to 98^oC in 20 minutes, and another fire went from 12^oC to 89^oC in just 5 minutes.

Such prescribed burns occur every Spring in this region — other examples include April 2019 and April 2010 .

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