GOES-13 0.63 µm visible channel images (click to play animation)

McIDAS images of GOES-13 0.63 µm visible channel data (above; click image to play animation) revealed the well-defined circulation of a mesocale vortex over far western Lake Superior on 28 November 2013. During the day, this mesovortex was slowly migrating southward toward the Apostle Islands of Wisconsin. As much as 7.5 inches of snow was reported north of Bayfield in far northern Wisconsin, likely a result of enhanced snowfall rates associated with the passage of the mesovortex.

Suomi NPP VIIRS 0.64 µm visible channel images (17:27 and 19:07 UTC)

AWIPS images of VIIRS 0.64 µm visible channel data from consecutive overpasses of the Suomi NPP satellite at 17:27 and 19:07 UTC (above) showed better detail in the structure of the mesovortex; the corresponding VIIRS 11.45 µm IR images (below) indicated that cloud top IR brightness temperatures were generally in the -25 to -30º C range (darker blue color enhancement), suggesting that cloud glaciation was likely.

Suomi NPP VIIRS 11.45 µm IR channel images (17:17 and 19:07 UTC)

A comparison of the 17:27 UTC VIIRS visible image with the 17 UTC RTMA surface winds and the 18 UTC NAM12 surface, 925 hPa, and 850 hPa winds (below) showed that neither the RTMA nor the NAM12 wind fields did a good job of locating the actual center of primary mesovortex circulation — demonstrating the value of satellite imagery for a more accurate diagnosis of such small-scale features.

Suomi NPP VIIRS 0.64 µm visible image (with RTMA surface winds, NAM12 surface, 925, and 850 hPa winds)

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GOES-13 6.5 µm water vapor channel image, with surface pressure and surface front analysis

An AWIPS-1 image of GOES-13 6.5 µm water vapor channel data (above) showed a large storm that was affecting much of the eastern US during the 26 November – 27 November 2013 period. Arctic air surging southward behind this storm system crossed the Gulf of Mexico, was funnelled through the mountain passes of southern Mexico, and eventually emerged into the Pacific Ocean in the Gulf of Tehuantepec. This type of “Tehauno wind event” tends to occur a few times each year during the cold season — a few other cases have been documented on this blog.

A series of AWIPS-2 images of GOES-13 10.7 µm IR channel data with overlays of surface and buoy reports and tropical surface analyses (below; click image to play animation) showed that the Gulf of Tehuantepec region was highlighted on 26 November as a region susceptible to developing Storm Force (48-55 knot) winds as the cold front approached from the north. Once the strong gap winds emerged from the southern coast of Mexico, parts of that area likely began to experience storm force winds.

GOES-13 10.7 µm IR images, with surface and buoy reports and tropical surface analysis (click to play animation)

The plume of dry air associated with the Tehuano wind event could be seen on AWIPS-1 images of the MIMIC Total Precipitable Water product (below; click image to play animation).

MIMIC Total Precipitable Water product, with tropical surface analysis (click to play animation)

During the day on 27 November, the hazy signature of blowing dust and sand could be seen streaming southward across the Gulf of Tehuantepec on McIDAS images of GOES-13 0.63 µm visible channel data (below; click image to play animation).

GOES-13 0.63 µm visible channel images (click to play animation)

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Meteosat-10 0.75 µm visible channel images (click to play animation)

The Mount Etna volcano — the tallest on the European continent, and one of the most active in the world — experienced an eruption on 23 November 2013. EUMETSAT Meteosat-10 0.75 µm visible channel images (above; click image to play animation) showed the explosive development of the volcanic plume beginning around 09:30 UTC; the plume then moved rapidly northeastward across far southern Italy, eventually moving over Albania around 13:00 UTC. A number of lightning strikes within the billowing ash plume can be seen in an HD-quality YouTube video.

Satellite signatures of an earlier eruption were discussed here and here.

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Meteosat-10 10.8 µm infrared channel images (click to play animation)

Cyclone Cleopatra moved through the central Mediterranean Sea, causing flooding in Italy and Sardinia (BBC News Link) with northeastern Sardinia particularly hard hit. The infrared imagery from Meteosat-10, above, and the water vapor imagery, below, shows the slow movement of the entire system within the Mediterranean basin, as well as the strong thunderstorms over Sardinia later in the day on 18 November. Note in the Infrared animation that the minor eruption of Etna, on Sicily, is apparent (as documented here).

Meteosat-10 6.2 µm water vapor channel images (click to play animation)

A higher-resolution view centered on Sardinia, below, shows the redevelopment of strong thunderstorms (inferred by cold cloud tops on the IR imagery) over Sardinia ending after 1800 UTC on 18 November as dry air swept north. The visible imagery (bottom) is also testimony to the training aspect of this convection. (Hat tip to Byron Grisham at NOAA/OSPO for alerting us about this noteworthy storm)

Meteosat-10 10.8 µm infrared channel images (click to play animation)

Meteosat-10 0.7 µm visible channel images (click to play animation)

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