Suomi NPP VIIRS 11.45 µm IR channel and 0.7 µm Day/Night Band images (with overlays of surface reports and surface analysis)

AWIPS images of Suomi NPP VIIRS 11.45 µm IR channel and 0.7 µm Day/Night Band images (above) showed a night-time view of an intense mid-latitude cyclone that was centered just east of the Canadian Maritimes at 06:09 UTC or 2:09 AM local time on 22 March 2013. The strongest surface wind gust seen at that time was 59 knots, west of the storm center along the eastern coast of Nova Scotia.

A similar daytime view using Suomi NPP VIIRS 11.45 µm IR channel and 0.64 µm visible channel images at 17:31 UTC or 1:51 PM local time is shown below. The highest surface wind gust seen was 60 knots, north of the storm center at Blanc Sablon, Quebec.

Suomi NPP VIIRS 11.45 µm IR channel and 0.64 µm visible channel images (with overlays of surface reports and surface analysis)

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

The temporal evolution of the storm could be seen on 15-minute interval GOES-13 0.63 µm visible channel images (above) and 6.5 µm water vapor channel images (below). Note the formation of parallel cloud bands over the Gulf of Saint Lawrence, due to the interaction of the strong easterly to southeasterly winds with the higher terrain of the western portion of Newfoundland. A signature of these lee wave clouds immediately downwind of Newfoundland was also seen on the water vapor images — in addition to the formation of a standing wave over the far southwestern part of the island.

GOES-13 0.65 µm water vapor channel images (click image to play animation)

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GOES-13 0.63 µm visible channel image (with plot of surface air temperature)

The vernal equinox — commonly referred to as the “first day of Spring” in the Northern Hemisphere — occurred at 11:02 UTC on 20 March 2013. A GOES-13 full disk visible image at 11:45 UTC (above) showed the cloud features on the sun-lit portions of the Earth at that time, along with the large range of surface air temperatures: from -36 F or -38 C in northern Canada to 106 F or 41 C in western Africa (temperature contours). One of the more prominent features seen on the visible image was the large swirl of clouds associated with an occluded mid-latitude cyclone over the eastern North Atlantic Ocean (surface analysis).

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

Hat tip to Luis Rosa at the National Weather Service forecast office at San Juan, who alerted us to the presence of an undular bore that was moving southward toward Puerto Rico on 14 March 2013. The southward propagation of the wave clouds associated with the bore can be seen on McIDAS images of 1-km resolution GOES-13 0.63 µm visible channel data (above; click image to play animation). The passage of the bore also seemed to have an effect on the erosion of the marine boundary layer stratocumulus clouds.

An AWIPS image of 1-km resolution POES AVHRR 0.86 µm visible channel data with overlays of surface reports and the surface analysis (below) showed that a cold front was situated about 500 miles northwest of Puerto Rico — so the undular bore was located far in advance of this frontal boundary. As seen on the animation of GOES-13 visible images above, the wave clouds of the bore had dissipated by the time of the AVHRR image (17:38 UTC); at St. Thomas, Virgin Islands (station identifier TIST) the winds briefly shifted to northeasterly at 18-19 UTC, though it is unknown whether this wind shift was related to the arrival of the bore.

POES AVHRRR 0.86 µm visible channel image with surface reports and surface analysis

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Meteosat-3 11.5 µm IR channel images (click image to play animation)

The 12–14 March 1993 “Storm of the Century” (aka “the ’93 Superstorm” or “the Great Blizzard of 1993”) was one of the most significant storms to impact the eastern United States (NWS Wilmington NC summary). McIDAS images of EUMETSAT Meteosat-3 Infrared (11.5 µm) channel images (above) showed the storm as it initially began to experience rapid intensification in the Gulf of Mexico on 12 March. At the time, Meteosat-3 was on loan to the US and serving as the “GOES-East” satellite after the failure of GOES-6 in 1989.

On the following day (13 March), a larger-scale view of Meteosat-3 Infrared (11.5 µm) images (below) revealed the very large size of the storm as it moved along the Eastern Seaboard of the US. Some highlights of the storm included snowfall amounts as high as 56 inches at Mount LeConte in Tennessee, a wind gust to 144 mph at Mount Washington in New Hampshire, a minimum sea level pressure of 28.28 inches at White Plains in New York, and a post-storm record low temperature of -12º F in Burlington, Vermont.

Meteosat-3 11.5 µm IR channel images (click image to play animation)

The corresponding large-scale view of Meteosat-3 Water Vapor (6.4 µm) images (below) showed the well-defined dry slot and large comma head associated with the storm.

Meteosat-3 6.4 µm water vapor channel images (click image to play animation)

A GOES-7 Visible (0.65 µm) image at 18:01 UTC or 1:01 PM Eastern Time on 13 March (below) showed several interesting aspects of the storm, including widespread stratucumulus cloud streets over the Gulf of Mexico and the Atlantic Ocean (due to cold air advection over warmer waters), and also a large cloud arc in the Pacific Ocean south of Mexico, which was the leading edge of a Tehuano mountain gap wind event (see Schultz, et al, 1997). A rope cloud marked the leading edge of the strong cold front, which at the time of the image had plunged as far southward as Honduras in Central America.

GOES-7 0.65 µm visible channel image (click to enlarge)

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