Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
329 PM EST Tue Nov 21 2017
Valid 00Z Wed Nov 22 2017 - 00Z Fri Nov 24 2017
...Heavy rain possible over the Pacific Northwest...
...Rain changing to snow over parts of the Lower Great Lakes...
A front extending from the Lower Great Lakes roughly southwestward to the
Lower Mississippi Valley/Southern Plains will move east and southward to
off the Eastern Seaboard and off the Gulf Coast by Wednesday. An area of
rain and snow over parts of the Great Lakes will move eastward into
Northern New England by Wednesday evening and into Canada by late
Wednesday night. In the wake of the front, lake effect snow will develop
for a short time over parts of the Upper Great Lakes on Tuesday evening,
ending by Wednesday afternoon.
Meanwhile, areas of disorganized upper-level energy over the Southeast and
the Southern Plains will aid in producing showers and thunderstorms over
parts of the Western/Eastern Gulf Coast and parts of the Southeast through
Wednesday morning. The first bundle of energy moving off the Southeast
Coast overnight Tuesday will induce an area of low pressure off the
Carolina Coast just ahead of the cold front. The low will become a wave
of low pressure along the front over the Western Atlantic that will move
northeastward into the Canadian Maritimes overnight Wednesday. Overnight
Tuesday, the energy will develop rain over parts of the Carolinas into the
Mid-Atlantic that will move northward into Southern New England by
Wednesday morning and into Northern New England by Wednesday afternoon.
The rain will move off the New England Coast by Wednesday evening. The
second are of upper-level energy will move to the Eastern Gulf Coast and
likewise develop a wave of low pressure along the boundary over the
Eastern Gulf of Mexico overnight Wednesday into Thursday. The energy will
produce showers and thunderstorms over parts of Florida Wednesday evening
into Thursday, Thanksgiving.
More to Follow
Graphics available at www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php