Suomi NPP VIIRS 11.45 µm IR images (click image to play animation)

A sequence of AWIPS images of Suomi NPP VIIRS 11.45 µm IR data from 13 January to 15 January 2013 (above; click image to play animation) revealed a great deal of motion of the sea ice in the Arctic Ocean off the north coast of Alaska. Surface stations along the Alaskan coast were reporting strong easterly winds during this time period, with gusts in excess of 40-50 knots — these strong winds were helping to push the sea ice westward. Also evident in the images was the relatively warm signature (cyan to yellow color enhancement) exibited by numerous “cracks” in the sea ice — it is unclear whether these features are simply weaknesses in the thick ice pack, or actual leads of open water.

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

A Mesolow developed over Lake Superior today and moved rapidly northeast towards Ontario. As the system moved near Pukaskwa, ON (48.6 N, 86.3 W), winds there shifted from northwest at 3 knots at 1800 UTC to northeast at 5 knots at 1900 UTC to west at 7 knots, gusting to 16 knots at 2000 UTC. (An animation of surface plots overlain on the satellite imagery is here). The mesolow seems to have developed as an interaction with the topography on Isle Royale. Lake Surface temperatures are in the mid-30s, as is typical this time of year, and 850-mb temperatures (as measured at International Falls at 1200 UTC) were around -18 C.

GOES-15 0.62 µm visible channel images (click image to play animation)

GOES-West provided an oblique view of the system development, shown above.

Hat tip to the National Weather Service in Marquette Michigan for first alerting us to this system’s presence!

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GOES-15 (left) and GOES-13 (right) 0.63 µm visible channel images (click image to play animation)

McIDAS images of GOES-15 (GOES-West) and GOES-13 (GOES-East) 0.63 µm visible channel data (above; click image to play animation) showed the development of a large area of blowing dust that formed in response to high winds along and in the wake of a strong cold frontal boundary (18 UTC surface analysis) that was moving from eastern Colorado into western Kansas on 11 January 2013. Winds gusted to 56 mph in Burlington, Colorado and gusted to 49 mph in Goodland, Kansas (where the surface visibility was reduced to 1.75 miles by the blowing dust).

A closer view using 375-meter resolution (projected onto a 1-km AWIPS grid) Suomi NPP VIIRS 0.64 µm visible channel and the corresponding false-color Red/Green/Blue (RGB) image at 19:23 UTC or 12:23 PM local time (below) revealed the banded structure of the blowing dust cloud,  which was verified by a photo taken around 19:17 UTC from an aircraft over eastern Colorado by William Straka (CIMSS). Also evident on the VIIRS images was  the presence of a number of aircraft dissipation trails (or “distrails”) and “hole punch clouds” across parts of central and eastern Kansas. The brighter pink color enhancement within the distrails and hole punch clouds indicated the glaciation of supercooled water droplets in those portions of the cloud deck that were penetrated by aircraft.

Suomi NPP VIIRS 0.64 µm visible channel and false-color Red/Green/Blue (RGB) image

In a comparison of a 20:33 UTC (or 1:33 PM local time) MODIS 0.65 µm visible image with the corresponding MODIS 11-12 µm IR brightness temperature difference (below), the most dense areas of blowing dust were highlighted by the lighter cyan colors.

MODIS 0.65 µm visible channel and 11-12 µm IR brightness temperature difference product

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Suomi NPP VIIRS 0.64 µm visible channel, 3.74 µm shortwave IR channel, and 11.45 µm IR channel images

A comparison of AWIPS images of Suomi NPP VIIRS 0.64 µm visible channel, 3.74 µm shortwave IR channel, and 11.45 µm IR channel data (above) showed a broad “vog” plume streaming westward off the Big Island of Hawaii on 10 January 2013. The primary source of this vog plume was likely the active Kilauea volcano — and the 3.64 µm shortwave IR image revealed a small “hot spot” at the summit of the volcano, which exhibited a brightness temperature value of 49.5º C (orange color enhancement).

The VIIRS 0.64 µm visible channel image with an overlay of 1-hour interval MADIS atmospheric motion vectors (or “satellite cloud-tracked winds”) showed the typical easterly trade wind flow regime that usually transports the vog plume westward away from the Hawaiian Islands (below). However, synoptic-scale disturbances that disrupt this trade wind flow can cause the vog plume to move over inhabitied portions of the islands, causing air quality problems.

Suomi NPP VIIRS 0.64 µm visible channel image + MADIS 1-hour interval atmospheric motion vectors

Other examples of Hawaiian vog plumes can be found here on the CIMSS Satellite Blog.

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