The Storm Prediction Center issued a Mesoscale Discussion (#337 for 2022) at 1918 UTC on 25 March 2022 for southern Wisconsin/northern Illinois discussing the possibility of convective snow showers late in the day on 25 March 2022. The toggle above shows gridded NUCAPS values of 500-mb Temperature over the upper midwest in a toggle with the GOES-16 Day Cloud Phase Distinction RGB (here are the gridded NUCAPS toggled with sounding availability points). A ribbon of cold air — colder than -30^o C — is present over central MN, moving southward, and the coldest air overlaps the region in the Day Cloud Phase Distinction where, based on the color, one might infer the greatest vertical development to the clouds.

The animation below shows the Day Cloud Phase Distinction plotted over the (clear sky only) Lifted Index. Extensive clouds are preventing the Level 2 Lifted Index from supplying useful imagery where clouds exist (unlike the NUCAPS-derived information above)

By 2100 UTC, evidence of convection in the Day Cloud Phase Distinction continues to increase over southeast Minnesota/northeast Iowa and southwestern WIsconsin (the yellow/greenish tinge to the RGB). Lifted Index from GOES-16 continues to show coverage suppressed by cloud cover. However, Lifted Index from the Polar Hyperspectral Sounding/Microwave and ABI modeling system (discussed here; imagery available here; these data will be demonstrated at the Hazardous Weather Testbed) shows more coverage, indicating two corridors of weaker stability into Illinois and Wisconsin.

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Some of the imagery in this blog post was produced using the NOAA/NESDIS TOWR-S Cloud Instance of AWIPS. Thank you!

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GOES-16 (GOES-East) Mid-level Water Vapor (6.9 µm) images (above) displayed an isolated vortex of very dry air moving over Texas and Louisiana on 24 March 2022. Contours of RAP40 model PV1.5 Pressure — a representation of the “dynamic tropopause” — indicated that this dry feature was a Potential Vorticity (PV) anomaly, which forced the local tropopause to briefly descend as low as the 650 hPa pressure level as the feature passed over that region.

Aircraft flying in the vicinity of such PV anomaly vortices sometimes encounter turbulence within the middle to upper troposphere, near altitudes where the tropopause is being perturbed — and in this case there were 3 pilot reports of moderate turbulence near or within the dry water vapor vortex signature (below).

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Hyperspectral soundings — for example the Cross-track Infrared Sounder (CrIS) on NOAA-20/Suomi-NPP and the Infrared Atmospheric Sounding Interferometer (IASI) on MetOp — observe the atmosphere at thousands of wavelengths in the near-infrared and infrared part of the electromagnetic spectrum. The excellent spectral resolution allows for good vertical resolution of temperature and (especially) moisture in the atmosphere; Polar Hyperspectral Soundings (PHS) are created from these data to give profiles of temperature and moisture. Data fusion, described in this Smith et al. paper from 2020, relates ABI information to PHS when the polar observations are made (the technique used is a bit different from the GEO+LEO technique described in this Weisz and Menzel paper from 2019). Those relationships are subsequently carried forward in time, thereby exploiting both the excellent spectral resolution available from polar satellites and the excellent spatial and temporal resolution from ABI. Qi Zhang and Bill Smith, Sr. at Hampton University are running a model that takes advantage of this data fusion. Output from this modeling effort have been previously discussed here and here on this blog, and is available here. In the past year, the modeling effort has expanded to include microwave information (from the Advanced Technology Microwave Sounder (ATMS) on NOAA-20/Suomi-NPP) to give more accurate satellite-derived moisture information below the cloud-tops.

The imagery below shows forecasts of Significant Tornado Parameter from two different 3-km runs, one with a domain centered on the risk as defined by the Storm Prediction Center, one with a static domain. Note the close correlation between the region of larger values and the observed tornadoes. Results between the two forecasts are similar, but the false alarm rate is somewhat smaller in the small domain.

New Orleans LA was hit by a tornado (discussed here) after sunset on 22 March 2022. Tornado locations are shown by the inverted red triangles in the figures below. The Significant Tornado Parameters from the 3-km model that includes PHS data, microwave data, and ABI data has a maximum in the region of the tornado. This is useful information to have when anticipating the tornado development.

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The combination of polar hyperspectral soundings with ABI data has been explored since before the launch of GOES-R, and in fact back to about 2008! Funding for this effort has been supplied in the past by both GOES-R and JPSS Risk Reduction initiatives.

In the (distant) future, when NOAA’s Geostationary Extended Observations (GeoXO) satellite system is in orbit (click here for more information on GeoXO), routine soundings of the atmosphere will allow this type of modeling effort with better initial conditions because there will be a much smaller time between the observations (from Geostationary in the future vs. from Polar Orbiters now) and the model initialization.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) include time-matched SPC Storm Reports — and showed some of the widespread severe weather produced by thunderstorms that developed ahead of a cold front which was moving eastward across the Deep South on 22 March 2022. 

The severe weather persisted for several hours past sunset, as displayed below by GOES-16 “Clean” Infrared Window (10.35 µm) images ending at 0416 UTC on 23 March (11:16 pm CDT on 22 March).

A closer look at the development of a supercell thunderstorm that produced an EF-3 tornado in Arabi (within the eastern portion of the Greater New Orleans metropolitan area) is shown below.

Tuesday's EF-3 tornado had an est. peak wind of 160 mph, making it the strongest tornado to impact Orleans/Jefferson/St. Bernard Parishes on record. It's also only the second F-/EF-3 or higher tornado. A small section of New Orleans East were impacted by both EF-3 tornadoes. pic.twitter.com/IlEFLjLHGq

— NWS New Orleans (@NWSNewOrleans) March 25, 2022

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