Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
318 AM EST Thu Nov 18 2021

Valid 12Z Thu Nov 18 2021 - 12Z Sat Nov 20 2021

...Another around of moderate to heavy rain and strong winds will move
into Pacific Northwest tonight; high elevation snow farther inland on
Friday into the weekend...

...Wintry precipitation this morning and again Friday morning over
interior New England; lake-effect snow will develop downwind from the
Great Lakes into Friday...

A low pressure system moving through the eastern Pacific will bring the
next round of active weather into the Pacific Northwest tonight.  Moderate
to heavy rain ahead of this system can be expected to overspread the
Washington/Oregon coasts together with increasing winds tonight into
Friday morning.  Unlike its recent predecessor, this storm is forecast to
quickly weaken as it moves farther inland on Friday, bringing modest
amounts of mountain snows across the Intermountain region into parts of
the northern Rockies later on Friday and into the weekend.

Meanwhile, a cold front extending from a low pressure system in eastern
Canada will move through the eastern U.S. and then off the Eastern
Seaboard by Friday morning.  This will bring an axis of rain and some
thunderstorms through much of the area today and into tonight.  Behind the
boundary, lake-effect snow will begin to develop today from west to east
across the Great Lakes region along with blustery winds.  Over northern
New England, some wintry precipitation ahead of a warm front will change
over to rain showers during the day as the warm air arrives.  The warmth
will be very short-lived, however, as the cold front will quickly move
through the area tonight.  Interior New England may see the rain ending as
wet snow over the higher elevations behind the front later tonight along
with blustery winds and colder temperatures.  Meanwhile, nice fall weather
along the East Coast with much above normal temperatures today will be
replaced by a large dome of cold air coming through the mid-section of the
country on Friday.  Milder than normal conditions will return to the 
High Plains on Friday as a new low pressure system attempts to develop 
in a relatively dry environment.

Elsewhere, tropical moisture from the western Caribbean Sea is being
lifted north toward Florida ahead of a weak upper-level trough moving
across the Gulf of Mexico.  Some enhanced rainfall can be expected to move
across southern Florida today.  By Friday morning, much of the rain should
be on its way eastward into the Atlantic as a cold front dips into
northern Florida.  This front will keep a good chance of showers and
thunderstorms into the weekend for the east coast of southern Florida.

Kong


Graphics are available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php