Snow cover in southeastern Virginia and northeastern North Carolina
Around an inch of snow accumulated across parts of southeastern Virginia and northeastern North Carolina during the overnight hours on 28-29 January 2007. This patch of snow cover was evident the following morning on GOES-12 visible channel imagery (above). A Java animation of visible images shows that the northern portion of the snow cover (in Virginia) began to melt rather quickly during the late morning hours. The darker region within the area of snow cover is the Great Dismal Swamp National Wildlife Refuge; snow was not able to accumulate over most of that marshy surface, so it does not appear as white as the surrounding snow-covered land (MODIS true color image). In addition, we can see that the snow cover extended as far to the southeast as coastal sections of the Albemarle and Pamlico Sounds in North Carolina.
By examining AWIPS imagery of some of the MODIS channels, we can confirm that this particular image feature is indeed snow on the ground: snow is a very strong absorber at the 2.1 µm wavelength, and therefore shows up as a dark feature on the Snow/Ice (Band 7) image (below, upper right panel). Note that the MODIS IR brightness temperatures (below, bottom left panel) are several degrees colder in the region of snow cover (-5º to -8º C, darker blue enhancement) than over the surrounding bare ground (0º to -3º C, cyan enhancement).
