Wednesday, 05-11-2022, brought storm damage and copious amounts of lightning over Minnesota and parts of South Dakota, Iowa, and Wisconsin. The GOES-16 Geostationary Lightning Mapper (GLM) detected the flash extent density over these areas. A NEXRAD radar composite shows a large bow echo signature around 05-12-2022 01:25Z that spanned the entire lower half of Minnesota. Storms are still currently pushing through eastern Minnesota and northern Wisconsin and forecast to bring severe thunderstorms throughout the afternoon. There are also continuing threats of flooding in the Twin Cities and surrounding areas.
GOES-16 GLM Flash Extent Density and Band 13 reflectance on 05-12-2022 from 00:03 UTC to 16:43 UTC.GOES-16 Band 13 reflectance with NEXRAD Reflectivity on 05-12-2022 from 00:05 UTC to 16:45 UTC.
The GOES-16 GLM Flash Extent Density product is available on RealEarth here. Near-real-time GLM visualizations are available as well as archived visualizations of GLM going back 3-4 days.
RCM3 NRCS footprints from south to north, 00:13:28 through 00:13:55 on 5 May 2022 (click to enlarge)
Data on this website (if you click through to 5 May 2022) shows regions where the RCM constellation has produced data. There are very small footprint scenes (shown below) over the Red River of the North, where flooding is ongoing (blog post 1; blog post 2). The Normalized Radar Cross Section (NRCS) imagery within those small footprints is shown sequentially, from south to north, above. The NRCS imagery gives very high-resolution snapshots of flooded regions. This NRCS image from 00:13:39 has the largest extent of flooding within it.
A single image that shows the 6 scenes, aligned from south to north, is available here. (Warning: It’s large)
SAR Wind Imagery site, zoomed in over the North Dakota/Minnesota border (Click to enlarge)
Inundation detected by ABI and VIIRS imagery, 0000 UTC on 3 May 2022 (Click to enlarge)
Flooding has been detected by satellite along the Red River of the North for more than a week (see this blog post from late April). The image above shows the Flood Estimates (from this website). The image below (courtesy William Straka, CIMSS) shows a high-resolution downscaled Flood-water depth map derived from VIIRS imagery only.
Derived Flood Depth, 3 May 2022, from Suomi-NPP and NOAA-20 VIIRS imagery (Click to enlarge)
An interesting aspect of this flooded land is that it affecting the boundary layer of the atmosphere, as shown below. Band 2 imagery (0.64 µm) shows lake breeze clouds developing around the lake; the Band 3 imagery (0.87 µm), farther below, better articulates the location of the land/water boundary. Dryer air moving in later in the day leads to dissipation of the clouds.
GOES-16 Band 2 Visible (0.64 µm) imagery, 1501 – 2201 UTC on 3 May 2022 (Click to enlarge)GOES-16 Band 3 Near-Infrared (0.87 µm) imagery, 1501 – 2201 UTC on 3 May 2022 (Click to enlarge)
NOAA-20 overflew this region at around 1800 UTC on 3 May 2022. The toggle below (using imagery taken from the CIMSS Direct Broadcast site for NOAA-20 located here), shows VIIRS Bands I01 through I04 (0.64 µm, 0.86 µm, 1.61 µm and 3.74 µm) at that time. The lake-breeze clouds are very apparent, and the cold waters of the lake are also obvious in the I04 imagery.
NOAA-20 VIIRS imagery, I01 (0.64 µm), I02 (0.86 µm), I03 (1.61 µm) and I04 (3.74 µm), at 1800 UTC on 3 May 2022 (Click to enlarge)
Thanks to Carl Jones, WFO FGF, for drawing attention to the lake breezes!
ABI/VIIRS Flood/Inundation Product valid 0000 UTC 26 April 2022 (Click to enlarge)
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.
7-day precipitation ending 1200 UTC on 27 April 2022 (Click to enlarge)
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).
GOES-16 Band 2 (0.64 µm), Band 5 (1.61 µm) and Day Land Cloud RGB, all at 1646 UTC on 27 April 2022 (Click to enlarge)
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.
Webcam imagery showing the Red River of the North under Sorlie Bridge in East Grand Forks, Minnesota, 21-27 April 2022 (Click to enlarge)
