1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched SPC Storm Reports — and showed the development of 2 supercell thunderstorms near the New Mexico / Texas Panhandle border late in the day on 23 May 2022. The northern storm produced hail as large as 2.50 inches in diameter, while the southern storm produced a very large tornado and damaging winds as strong as 80 mph. Signatures of Above-Anvil Cirrus Plumes (reference | VISIT training) were also seen.

In the corresponding 1-minute GOES-16 “Clean” Infrared Window (10.35 µm) images (below), warmer AACP signatures (shades of yellow) were evident, downwind of cold overshooting tops — these pulsing overshooting tops exhibited infrared brightness temperatures as cold as -77ºC.

https://twitter.com/southernon_wx/status/1528960198815227904

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GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed that a decaying Mesoscale Convective System (MCS) produced a low-level Mesoscale Convective Vortex (MCV) over the Gulf of Mexico on 22 May 2022. The coldest MCS overshooting tops exhibited  infrared brightness temperature of -77C around 1401 UTC. GOES-16 Visible (ABI spectral Band 2) Derived Motion Winds tracked MCV cloud motions with velocities as high as 38 knots. As the MCV approached the Gulf Coast, its vorticity to helped to initiate the development of new convection just to the north.

GOES-16 Visible images from the CIMSS Tropical Cyclones site (below) include contours of deep-layer wind shear at 20 UTC — and showed that Invest 90L was moving northward in an environment characterized by low values of shear.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) and “Clean” Infrared Window (10.35 µm) images (above) showed thunderstorms that moved across the northern portion of Lower Michigan on 20 May 2022. These storms produced hail (up to 3.0 inches in diameter), damaging winds (as high as 76 mph) and an EF-3 tornado that struck Gaylord (SPC Storm Reports | NWS Gaylord summary). Note that METAR reports were not available at Gaylord (and also about 30 miles to the west-southwest, at Bellaire) after the time of the tornado and damaging wind reports, due to widespread power outages (which affected about 1/3 of customers in Ostego County). 

A 2-panel comparison of GOES-16 Visible and Infrared images — which includes time-matched plots of SPC Storm Reports — is shown below.

Pulsing overshooting tops exhibited cloud-top infrared brightness temperatures as cold as -79^oC — which represented an Equilibrium Level (EL) overshoot of 1 to 1.5 km, according to a special Gaylord rawinsonde launched at 19 UTC (below).

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A toggle between GOES-16 Visible and Infrared images at 1948 UTC (above) includes the initial tornado report location plotted in blue. Note the offset between the overshooting top and the tornado report — this is due to parallax (below).

As the thunderstorms initially began moving inland from Lake Michigan and producing damaging winds near the northwest coast of Lower Michigan, a toggle between Suomi-NPP VIIRS True Color RGB and Infrared Window (11.45 µm) images (below) revealed overshooting tops with infrared brightness temperatures as cold as -87.7^oC (darker purple enhancement).

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ProbSevere (version 3) is an online tool that is available at this link. It gives the probability that the designated radar object will product severe weather in the next 60 minutes, and it was designed to be used in conjunction with other radar, satellite and model data to increase confidence in warning issuance. It is available online here; ProbSevere (version 2) is also online — and available within AWIPS. The RealEarth-based readout, above, shows the radar object that produced the EF-3 Tornado in Gaylord. (Click here for the NWS Gaylord writeup). ProbSevere values were consistently high with the radar object thoughout the trek across the northern Lower Peninsula of Michigan. Here is an image showing the accumulated ProbSevere values across northern Michigan (from this RealEarth link)

Read-outs of PSv3 and PSv2 values are available at this link, and the plot for the radar object in the animation above (#170831) is shown below (Here is a permanent link that allows you to view values!). Of note here is that PSv2 values are larger than PSv3 values. This is because PSv3 is better calibrated. For example, the Gaylord Tornado has a ProbTor value (plotted in red) of 90%! However, it is not the case that ProbTor (version 2) predictions with values of 90% lead to tornadoes 90% of the time: ProbTor v2 is overpredicting values in that case. ProbTor (version 3) is better calibrated, and the lower values are more in line with observations. Users familiar with ProbTor version 2 will need to adjust their expectations when transitioning to ProbTor version 3 (or indeed from any of the ProbSevere version 2 products to ProbSevere version 3 products).

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NOAA-20 overflew the region of severe weather just before 1800 UTC (link). Gridded NUCAPS fields from this site, below, show marked instability over the northwestern Lower Peninsula of Michigan, especially in the 700-500 mb layer, where gridded values exceed 7 C/km. The gridded values also show a decrease in stability for any storms moving into the Lower Peninsula from the west; however, Quality Control flags (shown below in a toggle with 850-mb Temperature), show profiles that did not converge over Lake Michigan.

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