Strong Storm in the Mediterranean

November 19th, 2013 |
Meteosat-10 10.8 µm infrared channel images (click to play animation)

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)

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 10.8 µm infrared channel images (click to play animation)

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

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

Ice forming in Hudson Bay, Canada

November 19th, 2013 |
Suomi NPP VIIRS 0.64 µm visible channel images

Suomi NPP VIIRS 0.64 µm visible channel images

AWIPS II images of 375-meter resolution Suomi NPP VIIRS 0.64 µm visible channel data (above) showed the growth of new ice immediately offshore in the northwestern portion of Hudson Bay, Canada during the 17 November19 November 2013 time period. The northwesterly flow of cold arctic air in the Arviat, Nunavut (station identifier CYEK) region was also producing well-defined cloud streets over the open waters of Hudson Bay.

The corresponding false-color “Snow Cloud Discrimination” Red/Green/Blue (RGB) images (below) confirmed that the brighter white nearshore features seen on the visible images were ice — ice and snow cover appear as shades of red on the RGB images, in contrast to supercooled water droplet clouds which appear as varying shades of white.

Suomi NPP VIIRS "Snow Cloud DIscrimination" false-color RGB images

Suomi NPP VIIRS “Snow Cloud DIscrimination” false-color RGB images

On 18 November, a significant amount of young pack ice motion can be seen in the 104-minute period between the 17:16 UTC and 19:00 UTC VIIRS visible images (below).

Suomi NPP VIIRS 0.64 µm visible channel images

Suomi NPP VIIRS 0.64 µm visible channel images

Daily “stage of development” ice analyses from the Canadian Ice Service are shown below.

Canadian Ice Service daily ice analysis for northern Hudson Bay (17, 18, 19 November)

Canadian Ice Service daily ice analysis for northern Hudson Bay (17, 18, and 19 November)