March 2 - 4
1960
Snowfall amounts with
this late season nor'easter ranged from six inches along the Ohio
River to a foot in the mountains. Higher elevation in the
central West Virginia Mountains
topped 20 inches. This was the third highest average snow producing
Nor'easter.
It was precluded by
surface high pressure over the mid Atlantic
on the 2nd, while a second high pressure built into the northern
plains. The high pressure over the mid-Atlantic was stubborn and was
not initially displaced by a developing low pressure across Mississippi and Alabama
area. The high was shoved aside by 00Z on the 3rd when the
surface cyclone in the Gulf Coast
states headed northeast. With the close proximity between the high and
low pressure, a strong pressure gradient developed bringing windy conditions
to West Virginia.
Coastal cyclogenesis commenced off the Carolina coastline between
00Z and 12Z on the 3rd. The coastal low raced up the eastern
seaboard reaching the Jersey shoreline by the evening of the 3rd. The
coastal low deepened 45mb in 30hrs from 6Z on the 3rd to 12Z on the
4th. The minimum central pressure fell to 960mb off New
England. As the surface low hugged the eastern seaboard,
the occluded low traversed up the windward side of the Appalachians.
As the surface low passed east of the southern Appalachians,
an inverted trough of low pressure developed that focused moderate to
heavier snow in the mountains.
The 850mb analysis
was most interesting. A low initiated in the southern high plains then
intensified rapidly across Texas due to a low level jet. By 00Z on the
3rd, the low became cut off in the vicinity of Memphis, TN.
Height falls upstream of the low allowed a continued northeast propagation
through March 3rd into the 4th. The 850mb moved
from southwestern Tennessee to Roanoke,
VA in a span of 12 hours,
which correlated well with the swift movement of the surface cyclone.
Strong cyclonic flow on the backside of the system kept snow going in
the West Virginia
Mountains. As the
850mb low passed south and east of the West
Virginia, 850mb temperatures remained between
0C to -5C, which kept the thermal profile conducive for snow.
A negatively tilted
500mb trough strengthened as it ejected out of the Rockies.
Meanwhile an upper level jet deepened as the trough propagated eastward
across the Gulf Coast
states on the 2nd and 3rd. A cut off low developed
on the evening of the third over the eastern Great
Lakes. The upper low then moved into the Atlantic and intensified
further, while yet another low dove into the elongated trough axis that
extended from the western Great Lakes to the New England.
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