Summary of the February 18 - 20th Nor'easter

February 18 - 20^th 1979

This storm ranks six of the highest snow producing Nor' easters of all time to affect the state of West Virginia. It is referred to as the "President's Day" storm. Five to eight inches of snow was common outside the mountains. While in the higher elevations upwards of a foot of snow fell. The bulk of the snow fell across Washington D.C. to Baltimore to Philadelphia metro areas where 12 to 18 inches was observed.

A strong high pressure of 1048mb built east across the Great Lakes on the night of the 17^th into the morning of the 18^th. At peak intensity, it reached 1050mb, and set many record low temperatures over the northeastern United States. The high was nearly stationary across northern New England during the time period when snow fell across West Virginia. With such a massive dome of cold air sitting to our northeast, this enabled sub-freezing temperatures to stay entrenched across the mid-Atlantic. Low pressure ejected out of the northern Gulf of Mexico then tracked up the eastern seaboard. This feature brought snow to most of the mid-Atlantic and New England. A secondary low developed across the middle Ohio Valley during the night of the 18^th and was responsible for most of the snow across West Virginia. The main surface low did supply moisture aiding the other low pressure. Although, the coastal low was the reason heavy snow occurred on the lee side of the Appalachians northeast into New England. As time went on, the low that traversed the Ohio Valley weakened and was absorbed by the coastal cyclone.

The 850mb low was an open wave riding northeast from the mid Mississippi river valley before it became closed off the Virginia coast With the northeast track of the cyclone, West Virginia was placed in the synoptically favored northeast quadrant of the 850mb low. In addition, the West Virginia was bounded by the -5 to -10C isotherm, another favored region for moderate to heavy snowfall.

The 500mb charts echoed a similar theme of the surface and 850mb plot with the storm being a weak fast moving system until it reached the coast when it underwent rapid intensification. Zonal flow aloft was present on the 18^th with an embedded upper level disturbance, which crossed the central United States. As the weak area of low pressure interacted with the subtropical jet along the Gulf Coast, the upper level trough intensified. The base of the trough passed across Kentucky and continued east over Virginia and North Carolina. 500mb confluence associated with the jet stream positioned the entire area in a favorable sector of the jet, therein enhancing snowfall rates on the 19^th and 20^th.

Back To Nor'easter page