McIDAS images of 1-km resolution GOES-13 (GOES-East) 0.63 µm visible channel data (above; click image to play animation) showed the development of widespread plumes of blowing dust across parts of southwestern Nebraska, northwestern Kansas, and eastern Colorado on 16 January 2014. Strong northerly to northwesterly winds in the wake of a morning cold frontal passage were  gusting over 40 knots across the entire region, with a peak wind gust of 64 knots in Broken Bow, Nebraska. These strong winds easily lofted the dry soils (the area was experiencing extreme drought conditions), which reduced surface visibilities and caused multiple vehicle accidents in Colorado and Kansas.

A closer view of the blowing dust using a 250-meter resolution Aqua MODIS true-color Red/Green/Blue (RGB) image from the SSEC MODIS Today site (below) clearly showed the source region of many of the dust plumes in southwestern Nebraska. The blowing dust plumes in eastern Colorado are not easily seen, due to patchy middle and high level clouds drifting over the region at that time.

A larger-scale view of the MODIS true-color image can be seen below, visualized using Google Earth.

For additional information and imagery of this blowing dust event, see the RAMMB GOES-R Proving Ground blog.

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With ample illumination by moonlight (the Moon was in the Waxing Gibbous phase, at 98% of full), an AWIPS image of Suomi NPP VIIRS 0.7 µm Day/Night Band data was able to provide a “visible image at night” that showed the extensive ice coverage in Lake Erie at 06:42 UTC or 1:42 AM local time on 13 January 2014 (above). The mean ice concentration of Lake Erie was 76.8% at that time (up from less than 20% at the begining of January). Note that there was no signal of any potential fog/stratus over the lake on the corresponding 11.45-3.74 µm IR brightness temperature difference “fog/stratus product”, and very little thermal contrast seen in the 11.45 µm IR image.

Farther to the south over the Gulf of Mexico, the 08:21 UTC or 2:21 AM local time VIIRS 0.7 µm Day/Night Band image (below) showed large thunderstorms, with cloud-top shadowing from overshooting tops as well as a few bright “lightning streaks” due to cloud illumination by intense lightning activity at the time the instrument was scanning the region. Overlays of cumulative 1-hour cloud-to-ground lightning strikes indicated over 2400 strikes ending at 08 UTC, and over 1800 strikes ending at 09 UTC over the area of the satellite scene. A comparison with the corresponding 11.45 µm IR image showed that the coldest cloud-top IR brightness temperatures were -65º C over the northern convective complex, and -73º C over the southern convective complex.

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Looking at a global composite of IR imagery from the SSEC RealEarth web map server (above), Cyclone Ian (07 P) in the South Pacific Ocean was a rather compact storm — however, a time series plot of the Advanced Dvorak Technique (below) showed that Cyclone Ian experienced a period of rapid intensification to Category 4 strength on 10 January 2014 (21 UTC Joint Typhoon Warning Center advisory).

SSEC RealEarth IR imagery (above; click image to play animation) and visible imagery (below; click image to play animation) showed the well-defined eye that was exhibited by Cyclone Ian during this period of rapid intensification on 10 January, as the storm moved slowly south-southeastward across the island nation of Tonga.

On 11 January, water vapor channel imagery from the CIMSS Tropical Cyclones site (below) showed the continuation of the impressive channel of poleward outflow from Cyclone Ian, which was enhanced by the presence of a mid-latitude trough passing to the south of the tropical cyclone.

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GOES-13 has been placed into Super Rapid Scan Operations (SRSO) mode today to support the OWLeS program over the eastern Great Lakes, providing periods of 1-minute interval imagery each hour. The extraordinary cold air over the eastern United States is producing heavy lake-effect snows over downwind of Lakes Erie (above) and Ontario (below). Storm total snowfall amounts were as high as 60 inches;  for additional information on this event, see the Wasatch Weather Weenies and Jim LaDue view blogs.

In a faster animation of GOES-13 SRSO visible images covering Lake Erie (below; click image to play animation; also available as an MP4 file), the motion of ice in the western portion of the lake could be seen; the formation and intensification of organized lake-effect snow bands occured over the ice-free open waters in the central and eastern parts of Lake Erie.

To supplement the GOES-13 SRSO images, a comparison of AWIPS images of Terra MODIS 0.65 µm visible channel and 11.0 µm IR channel data (below) showed the well-defined lake-effect snow (LES) bands streaming off of Lake Erie and Lake Ontario at 15:28 UTC (10:28 AM local time). At this time, surface visibility was restricted to 1/16 mile with heavy snow at Buffalo, New York (KBUF); other notable peak wind gusts included 46 knots at Waterton, New York (KART), 49 knots at Point Petre, Ontario (CQWP), and 50 knots at Long Point (CWPS) and Port Colborne (CWPC) Ontario. Metop ASCAT surface scatterometer winds were as high as 62 knots over Lake Erie and 46 knots over Lake Ontario. The coldest cloud-top IR brightness temperatures were -39º C immediately downwind of Lake Ontario, and -35º C immediately downwind of Lake Erie.

About 3 hours later (at 18:17 UTC or 1:17 PM local time), a similar comparison of Suomi NPP VIIRS 0.64 µm visible channel and 11.45 µm IR channel images (below) showed the 2 LES bands as they continued to organize and intensify. Surface visibility had dropped to 0 miles with heavy snow and blowing snow (and a peak wind gust of 41 knots) at Buffalo (KBUF). Other notable peak wind gusts included 41 knots at Watertown (KART) and 42 knots at Fort Drum (KGTB) in New York, 51 knots at Point Petre (CQWP), and 55 knots at Long Point (CWPS) and Port Colborne (CWPC) in Ontario. The Lake Ontario LES band had extended farther inland, with Saranac Lake, New York (KSLK) reporting visibility reduced to 1 mile with snow. Cloud-top IR brightness temperatures remained about the same: -39º C downwind of Lake Ontario, and -34º C immediately downwind of Lake Erie.

It is interesting to point out that there were a few cloud-to-ground lightning strikes downwind of Lake Ontario during the preceeding night-time hours; 1-hour lightning strikes are overlaid on a comparison of Suomi NPP VIIRS 0.7 µm Day/Night Band and 11.45 µm IR images at 06:54 UTC or 1:54 AM local time (below). In addition, note the small packet of gravity waves seen propagating southward (away from the area of lightning strikes) on the IR image. Isolated cloud-to-ground lightning strikes continued in this area until the early morning hours, as seen in an animation of GOES-13 IR images.

While not related to the OWLeS field experiment, it was interesting to examine GOES-13 SRSO visible channel images farther to the west over Lake Superior (below; click image to play animation; also available as an MP4 file), which displayed the following: (1) widespead multiple LES bands over much of the lake, which produced as much as 12 inches of snowfall near Deer Park (snowfall reports | Google maps), (2) a curious “solitary standing wave” feature that was oriented roughly parallel to the coastline of the eastern Upper Peninsula of Michigan east of Munising (station identifier KP53), and (3) packets of terrain-induced gravity waves both upwind and downwind of Isle Royale in the northwestern part of the lake (in addition to patches of lake ice both northwest and northeast of the island).

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