A 50- to 60-vehicle crash over central Schuylkill County (in Pennsylvania), with fatalities, on north-bound Interstate 81 occurred at around 11 AM EDT (TV news report; radio report), which is 1500 UTC. Day Cloud Phase Distinction, above shows the characteristic yellow/green/chartreuse shading that is associated with snow in cold air moving over I-81 in central Schuylkill County just before the reported time of the crashes. A longer animation below (with sparse surface observations — note no observations in Schuylkill County) during the day shows ongoing snow squalls during the course of the day.

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1-minute Mesoscale Domain Sector GOES-16 (GOES-East) “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm), Fire Power and Fire Temperature (above) displayed the smoke plumes and thermal signature of the Crittenburg Complex of wildfires that developed south-southwest of Dallas-Fort Worth, Texas on 27 March 2022. Thermal signatures became evident around 1600 UTC or 11:00 am CDT; within 3 hours this fire was burning very hot, with 3.9 µm Shortwave Infrared brightness temperatures reaching 138.71ºC — the saturation temperature of ABI Band 7 detectors — as early as 1900 UTC. The Fire Temperature and Fire Power derived products are components of the GOES Fire Detection and Characterization Algorithm FDCA.

GOES-16 True Color RGB images created using Geo2Grid (below) showed that the smoke plume eventually drifted north-northeastward over parts of the Dallas-Fort Worth metro area.

A toggle between Suomi-NPP VIIRS True Color RGB and False Color RGB images at 2032 UTC is shown below. The images were downloaded and processed via the Direct Broadcast ground station at SSEC/CIMSS, and are available for AWIPS via LDM subscription.

About 12 hours later, nighttime signatures of the Crittenburg Complex were still apparent in Suomi-NPP VIIRS Day/Night Band (0.7 µm) and Shortwave Infrared (3.74 µm) images (below). The lights just north of the fire (seen in Day/Night Band imagery) were likely due to firefighting assets in that area, working to slow the northward spread of the fire.

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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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