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Vaisala Datasets in Northeast U.S. Snowstorm of February 2013 Ron Holle 11 February 2013
Vaisala Datasets in Northeast U.S. Snowstorm of February 2013Ron Holle11 February 2013
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The large snowstorm in the northeastern United States this past weekend had several interesting features shown by Vaisala datasets. Figure 1 shows the National Weather Service (NWS) radar imagery at 2015 EST on the evening of Friday, 08 February. It is apparent that a large circulation is present, but the eastern side of the storm is out of range of the land-based NWS radar network.
Figure 1
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National Lightning Detection Network (NLDN) data in Figure 2 show strokes from 1500 to 2059 EST on Friday the 8th. Negative cloud-to-ground strokes are shown by a minus sign, positive by plus, and cloud pulses by lightning symbols. Most lightning is southeast of New England over the ocean, while some short lines are coming from the southeast to northwest as the thunderstorms move into colder air. A few strokes and pulses are shown as they reach over land on Friday evening along the coasts of Connecticut and Rhode Island where thundersnowwas reported.
Figure 2
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An additional interesting Vaisala perspective during this period is provided in Figure 3 from the composite of road cameras available at the Tucson Vaisala Data Management Center. It shows views from 54 of the cameras along the Massachusetts Department of Transportation on late Friday afternoon when road traffic had been suspended.
Figure 3
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On the next day, Saturday, 09 February at 1515 EST, Figure 4 shows the center of the large and strong circulation offshore from the NE U.S. and Maritime Canada. There is a long south-to-north line to the east of the center over the ocean.
Figure 4
Center of low
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The intensity of this line is not necessarily apparent from satellite imagery alone, but GLD360 lightning data in Figure 5 indicate the line to have 1187 lightning strokes in active updrafts that are strong enough to produce lightning. Individual cells in this line tend to move from southwest to northeast, as shown by the color scale.
Figure 5
