One the forecast offices selected on 14 June 2022 in the Hazardous Weather Testbed was Tallahassee (WFO TAE). The animation above shows the evolution of a seabreeze front that moves slowly northward (as a mesoscale complex, part of a system that produced widespread wind damage earlier in the day (storm reports from 13 June and 14 June), moves southward). Convection develops along the sea breeze front. The animation of Convective Available Potential Energy (CAPE), below, from the Polar Hyperspectral Modeling System, shows a local maximum of CAPE along the coast initially; it then propagates inland with time. The 1- and 2-h forecasts predict with accuracy where the CAPE associated with the sea breeze front will be. That’s perhaps easier to view in the animation at the bottom that has the model CAPE field semi-transparent on top of the visible (0.64 µm) imagery.

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Additional Hazardous Weather Testbed blog posts can be found here. The third and final week of HWT concludes on Friday the 17th.

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GOES-16 (GOES-East) Shortwave Infrared (3.9 µm) “Red” Visible (0.64 µm) and Day Land Cloud RGB images (above) showed the subtle signature of black smoke which resulted from a vehicle accident and fire (several miles west of Interstate 94) in far southeastern Wisconsin on 14 June 2022. The smoke plume quickly dispersed as it moved rapidly northeastward. Even though the fire was quite small, a single 3.9 µm pixel located over the crash site briefly peaked at a brightness temperature of 40.06ºC at 1546 UTC (single image | animation).

GOES-16 True Color RGB images created using Geo2Grid (below) provided another view of the brief black smoke plume.

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A sequence of Suomi-NPP VIIRS Visible (0.64 µm), Shortwave Infrared (3.74 µm) and Infrared Window (11.45 µm) images at 2149 UTC and 2332 UTC (above) showed “before” and “after” views of a  pyrocumulonimbus (pyroCb) cloud that developed south of McGrath, Alaska late in the day on 11 June 2022. The coldest cloud-top infrared brightness temperature of the pyroCb cloud on the 2332 image was -48C.

A couple of hours later, preliminary / non-operational GOES-18 “Red” Visible (0.64 µm), Shortwave Infrared (3.9 µm) and “Clean” Infrared Window (10.35 µm) images (below) showed that the Little Hog Butte Fire — located southwest of Lake Minchumina (PAMH) — produced a larger and more long-lived pyroCb cloud, which then drifted east-northeastward from the fire source region. The coldest cloud-top infrared brightness temperature of that pyroCb cloud was around -48C. Smoke from this fire was reducing the surface visibility to 2 miles at times at Lake Minchumina. Particularly noteworthy was the fact that this was the first documented pyroCb over Alaska in 2 years.

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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 the development severe thunderstorms across parts of eastern Nebraska, southern Iowa and northeastern Kansas during the afternoon and early evening hours on 11 June 2022. In Kansas, rows of boundary layer feeder bands could be seen flowing northeastward into the growing Mesoscale Convective System. These storms produced several tornadoes, hail as large as 5.00 inches in diameter and damaging winds as strong as 83 mph.

In the corresponding 1-minute GOES-16 “Clean” Infrared Window (10.35 µm) images (below), pulsing overshooting tops exhibited infrared brightness temperatures as cold as -80ºC (violet pixels embedded within areas of bright white).

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