1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images — with and without an overlay of GLM Flash Extent Density (above) — showed the development of a large Mesoscale Convective System (MCS) that developed over North Dakota and began moving eastward into Minnesota on 17 July 2020 (surface analyses). These thunderstorms produced a variety of severe weather, and heavy rainfall with up to 6 inches in North Dakota and 4 inches in Minnesota.

1-minute GOES-16 Visible images (above) and Infrared images (below) include time-matched plots of SPC Storm Reports — of particular note was the wind gust of 101 mph (GOES-16 Visible / Infrared images) that occurred at a RAWS site in northeastern North Dakota around 2045 UTC, in the vicinity of a brief tornado. As the MCS continued to expand southward and eastward during the subsequent nighttime hours, it eventually produced damaging winds across northeastern South Dakota, much of Minnesota and northwestern Wisconsin.

Animations of CIMSS Clear Sky Convective Available Potential Energy (CAPE), Lifted Index (LI) and Total Precipitable Water (TPW) products (below), from this site, showed the rapid destabilization and moisture increase of the air mass south and southeast of the developing MCS; this corridor of moist and unstable air was feeding northward, helping to sustain MCS growth and propagation.

These severe thunderstorms with tall cloud tops provided a good demonstration of the parallax shift inherent in GOES imagery at higher latitudes. Time-matched comparisons of Infrared images from NOAA-20 at 1933 UTC and Suomi NPP at 2023 UTC with the corresponding images from GOES-16 (below) showed that the GOES images were shifted northwest of the more accurate NOAA-20/Suomi NPP images.  The superior 375-meter spatial resolution of the VIIRS instrument allowed subtle cloud-top gravity waves to be seen — and the VIIRS cloud-top infrared brightness temperatures were about 10ºC colder than those sensed by the ABI instrument. The 1933 UTC images were about 15 minutes prior to the tornado and 101-mph wind gust at Churches Ferry (located about 20 miles northwest of Devils Lake KDVL).

An image showing parallax correction vectors and distance for a 50,00 ft (15.2 km) cloud top feature at various points within the GOES-16 CONUS domain (below) is from this site — and indicated a southeastward correction of about 28-30 km (or 17-19 miles) over northern North Dakota. This is in good agreement with what was seen in the 2 VIIRS/ABI infrared image comparisons shown above.

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As a Mesoscale Convective System (MCS) over Kansas and Oklahoma decayed during the morning hours of 16 July 2020, GOES-16 (GOES-East) “Clean” Infrared Window (10.35 µm) and Near-Infrared “Cirrus” (1.38 µm) images (above) depicted widespread transverse banding — tendrils of cirrus clouds oriented perpendicular to the upper-tropospheric wind flow — along the northern periphery of the MCS. An AIRMET was issued for that region (advising of moderate turbulence between 30,000 and 43,000 feet), and there were numerous Pilot Reports (PIREPs) of light to moderate turbulence in the general vicinity of these transverse banding features.

A GOES-16 Turbulence Probability product (below) did show scattered pockets of 25-35% probability in the transverse banding region. However, this product is designed to diagnose turbulence potential in the vicinity of features such as fronts and fields of convection.

Such transverse banding cloud features are frequently observed around the periphery of decaying MCSs (for example, June 2018 and July 2016) and in the vicinity of strong upper-tropospheric jet streaks (for example, February 2020 and March 2016).

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The animation above steps between NUCAPS Sounding Availability points and MIRS estimates of Rain Rate derived from NOAA-20’s Advanced Technology Microwave Sounder (ATMS) instrument (and available via LDM download from CIMSS).  ‘Red’ points in NUCAPS sounding availability are usually associated with precipitation, and that relationship is apparent in the toggle.  With the exception of four red points in southwestern Colorado, falling precipitation is diagnosed by the ATMS where red points are shown.

A zoomed-in view of those 4 points in SW Colorado, superimposed on GOES-16 ABI Band 13 (10.3 µm) infrared imagery is shown below.  The profile at the green point in the middle of the red points is here;  you can also view the northernmost red point, the westernmost red point, the southeasternmost red point, and the other red point.  Note that all soundings are very similar;  a conclusion might be that for those points, conversion in the retrieval is not the cause of the red (the alternative reason for ‘red’ is failure in cloud clearing).

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Rain Rate is a GOES-16 level 2 Derived Product that uses the infrared bands on the Advanced Baseline Imager (ABI).  Satellite-derived rain products are especially important in regions where radar observations are unavailable (because of radar maintenance, or because no radar exists), or where observations are blocked by terrain (i.e., beam-blocking).  The toggle is zoomed in over the mesoscale systems over Kansas and Iowa/Missouri and includes the GOES-16 Clean Window, the GOES-16 Rain Rate and the MIRS Rain Rate (derived from direct broadcast data at UW-Madison CIMSS; information on MIRS Processing is here and here.) and a 1-hour radar-derived product. Each of these rainfall estimates have different spatial and temporal resolutions, and that makes intercomparison challenging.

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CIMSS (Cooperative Institute for Meteorological Satellite Studies) is now 40 years old, as it was established in 1980. From “about CIMSS: “… is a Cooperative Institute formed through a Memorandum of Understanding between the University of Wisconsin-Madison (UW-Madison), the National Oceanic and Atmospheric Administration (NOAA), and the National Aeronautics and Space Administration (NASA) in 1980. CIMSS operates as an institute within the Space Science and Engineering Center (SSEC)”.

The CIMSS mission includes three goals:

• Foster collaborative research among NOAA, NASA, and the University in those aspects of atmospheric and earth system sciences that exploit the use of satellite technology;
• Serve as a center at which scientists and engineers working on problems of mutual interest can focus on satellite-related research in atmospheric and earth system science;
• Stimulate the training of scientists and engineers in the disciplines involved in atmospheric and earth science.

The same image, but full resolution (11 MB).

Then and Now

The above image pair compare a NASA SMS from 1980 to an GOES-16 ABI true color composite from 2020. Both images are from July 14th. The GOES-16 data was generated using Geo2Grid software.

The data are via SSEC Data Services.

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