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30-second imagery of severe thunderstorms across Nebraska and Kansas

Overlapping 1-minute Mesoscale Domain Sectors provided 30-second interval GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) of severe thunderstorms (SPC storm reports) that developed across central Nebraska and northern Kansas along and ahead of an advancing frontal boundary (surface analyses) on 08 June 2019. Robust overshooting tops were very apparent with many of the storms, and a few... Read More

GOES-16

GOES-16 “Red” Visible (0.64 µm) images, with SPC Storm Reports plotted in red [click to play MP4 animation | 407 MB animated GIF]

Overlapping 1-minute Mesoscale Domain Sectors provided 30-second interval GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) of severe thunderstorms (SPC storm reports) that developed across central Nebraska and northern Kansas along and ahead of an advancing frontal boundary (surface analyses) on 08 June 2019. Robust overshooting tops were very apparent with many of the storms, and a few Above-Anvil Cirrus Plumes were also seen.

The corresponding GOES-16 “Clean” Infrared Window (10.35 µm) images are shown below. Numerous overshooting tops exhibited infrared brightness temperatures in the -70 to -75ºC range; note the appearance of a wave feature which propagated radially outward from an overshooting top in south-central Nebraska after 0030 UTC.

GOES-16 "Clean" Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play MP4 animation | 159 MB animated GIF]

GOES-16 “Clean” Infrared Window (10.35 µm) images, with SPC Storm Reports plotted in cyan [click to play MP4 animation | 159 MB animated GIF]

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Inland intrusion of marine stratus in south-central Alaska

1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) images (above) showed a fast-moving jet of marine layer stratus moving westward from the Seward-Chenega area into the far southern Cook Inlet in south-central Alaska on 08 June 2019. A narrow finger of the marine stratus penetrated farther inland across the lower elevations of... Read More

GOES-17

GOES-17 “Red” Visible (0.64 µm) images [click to play animation | MP4]

1-minute Mesoscale Domain Sector GOES-17 (GOES-West) “Red” Visible (0.64 µm) images (above) showed a fast-moving jet of marine layer stratus moving westward from the Seward-Chenega area into the far southern Cook Inlet in south-central Alaska on 08 June 2019. A narrow finger of the marine stratus penetrated farther inland across the lower elevations of Iliamna Lake (which is located between Pedro Bay and Kokhanok). Note that at 2245 UTC the GOES-17 Mesoscale Sector was shifted southward, to better monitor a Gulf of Alaska storm.

This inland intrusion of marine stratus was driven by the presence of a warm thermal trough across Interior and Southwest Alaska (surface analyses) — animations of 10-minute GOES-17 Full Disk visible imagery (below) included hourly plots of surface wind barbs and air temperature. Note that some sites farther inland across southwestern Alaska had temperatures in the upper 60s to low 70s F.

GOES-17 "Red" Visible (0.64 µm) images [click to play animation | MP4]

GOES-17 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in cyan and temperatures plotted in yellow [click to play animation | MP4]

At Iliamna Airport — located along the northern edge of Lake Iliamna — southeasterly winds gusted to 22 knots at 01 and 03 UTC (below).

Time series plot of surface reports from Iliamna Airport [click to enlarge]

Time series plot of surface reports from Iliamna Airport [click to enlarge]

A similar type of thermally-driven phenomenon is sometimes observed in the San Francisco Bay area, as shown here and here.

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Lake Michigan lake breeze

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the formation of a lake breeze along the western shore of Wisconsin — in the wake of a cold frontal passage — on 05 June 2019. This lake breeze enhanced surface convergence, which played a role in the formation of a thunderstorm that produced hail as large... Read More

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in cyan, temperatures plotted in yellow and SPC Storm Reports plotted in red [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in cyan, temperatures plotted in yellow and SPC Storm Reports plotted in red [click to play animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) showed the formation of a lake breeze along the western shore of Wisconsin — in the wake of a cold frontal passage — on 05 June 2019. This lake breeze enhanced surface convergence, which played a role in the formation of a thunderstorm that produced hail as large as 2.50 inches in diameter when a prominent overshooting top was evident (NWS Green Bay).

The lake breeze also caused sharp drops in surface air temperature — from low 80s to middle 50s F — along with fog reducing visibility to 0.5 mile or less at Milwaukee and Racine in southeastern Wisconsin (below). The arrival of lake breeze fog also restricted the visibility to 0.5 mile or less at Waukegan in northeastern Illinois.

Time series plot of surface reports from Milwaukee Mitchell International Airport [click to enlarge]

Time series plot of surface report data from Milwaukee Mitchell International Airport [click to enlarge]

Time series plot of surface reports from Racine Batten International Airport [click to enlarge]

Time series plot of surface report data from Racine Batten International Airport [click to enlarge]

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Mesoscale vortex along the Texas coast

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) revealed a mesoscale vortex near the Texas coast (in the general vicinity of Houston) on 05 June 2019. This could have been a Mesoscale Convective Vortex (MCV), but there is evidence to suggest that it was a remnant circulation of what was Tropical Invest 91L a few... Read More

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in cyan [click to play animation | MP4]

GOES-16 “Red” Visible (0.64 µm) images, with hourly surface wind barbs plotted in cyan [click to play animation | MP4]

GOES-16 (GOES-East) “Red” Visible (0.64 µm) images (above) revealed a mesoscale vortex near the Texas coast (in the general vicinity of Houston) on 05 June 2019. This could have been a Mesoscale Convective Vortex (MCV), but there is evidence to suggest that it was a remnant circulation of what was Tropical Invest 91L a few days earlier.

Using a 3-hourly 850 hPa Relative Vorticity product from the CIMSS Tropical Cyclones site (below), the northward migration of vorticity associated with Invest 91L could be followed from the Bay of Campeche on 02 June to the Texas coast on 05 June.

850 hPa Relative Vorticity product, from 00 UTC on 02 June to 00 UTC on 06 June 2019 [click to play animation]

850 hPa Relative Vorticity product, from 00 UTC on 02 June to 00 UTC on 06 June 2019 [click to play animation]

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