January 11-14th 1964
A 1044mb high pressure system built south into the Dakota's
on the 11th and then drifted slowly south into the central
plains. Meanwhile a second, but weaker surface anticyclone developed
in southern Ontario and slid east across northern New
England. With this double barrel high structure, cold air
was entrenched across much of the mid-Atlantic and Ohio
Valleys. The surface low, which initially
started in the front range of the Rockies, marched east across the southern
plains and lower Mississippi River Valley.
The low curved north similar to 850mb and 500mb circulations due to
a highly amplified trough. The surface low occluded off the southeastern
coast of Virginia then trudged northeast
up the eastern seaboard into New England.
Cyclogensis then occurred around Charleston,
SC, although there were hints that
a weak circulation developed in the northern Gulf of Mexico. The surface low intensified as it interacted
with the Gulf Stream off the South Carolina. The lowest
pressure reported was 982mb at 12Z on the 13th just off the
Maryland
shoreline. The occluded low tracked west of the Appalachians on the
12th and 13th, which was the culprit for the heavy
snow that fell across West Virginia. Much of
the state experienced greater than six inches of snow with highest amounts
of 12 inches in the mountains. Reference the table on the previous page
for a snowfall map for this event.
Upper level analysis depicted a 500mb shortwave that dove
south from the northern plains into Oklahoma. The associated
upper low became cutoff across Oklahoma
by 00Z on the 12th. The closed 500mb low strengthened as
it moved northeast up the Ohio Valley
on the 13th. The low went from 534dm over northeast Oklahoma
to 516dm during the evening of the 13th. With the track of
the upper low, West Virginia was situated
just left of the upper low track, a favored location to experience heavy
snowfall.
At 850mb,
the circulation mirrored the 500mb pattern as it commenced as an open
wave and strengthened rapidly across the southern plains. It became
closed off over Kansas
at 00Z January 12th. The 850mb low track was similar to the
500mb track as the low passed over the mountain state. Even though the
low tracked from central Kentucky to
Charleston, WV,
to Philadelphia,
PA, warm air was unable to intrude with a cold
airmass already in place. Temperatures initially
were -5C, however as the low tracked over central West
Virginia, they warmed to almost 0C in southern West
Virginia. The northern part of the state hovered
around -5C for the duration of the event. With the low passing to the
west, southerly winds brought an area of warm air into the coalfields,
although rainfall was observed only for a short period.
The following
indicators were satisfied that could assist forecasters to accurately
predict snow amounts.
1. The 850mb low moved northeast
2. West Virginia
was 1.5 degrees latitude to the left of the 850mb low track
3. -5C isotherm bisected the area of heavy snow.
www.weather.gov 
