January 25 to 27, 2004 Appalachian Cold Air Damming Event
This is a classic cold air damming event with a high pressure ridge over the Middle Atlantic and Northeast states. The dashed 32 oF line shows the southward push of cold air with time. The dashed line is blue in the first two images, then green in the third image.
Images from the National Centers for Environmental Information data archives.
1200 UTC (6 AM CST) January 25, 2004
1200 UTC (6 AM CST) January 26, 2004
1200 UTC (6 AM CST) January 27, 2004