Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
410 PM EDT Wed Oct 27 2021

Valid 00Z Thu Oct 28 2021 - 00Z Sat Oct 30 2021

...Anomalous low pressure system to spawn severe weather across Gulf Coast
into tonight followed by the Southeast on Thursday...

...Threat of flooding rains moving into the Mid-Atlantic states on
Friday...

...Wet pattern continues across the Pacific Northwest...

As the Nor'easter quickly moves away from the New England states, another
significant low pressure system is quickly developing over the southern
Plains and into the Deep South.  This system is bringing a swath of
moderate to heavy rain that extends through the mid-section of the country
from the Gulf Coast all the way to the Canadian border.  Severe
thunderstorms continue to march steadily from west to east into the lower
Mississippi Valley this Wednesday afternoon.  The low pressure system is
forecast to deepen while expanding in size as it moves slowly towards the
eastern U.S. during the next couple of days.  Much of the severe weather
threat will continue to progress eastward into the eastern Gulf states
tonight before overspreading the southeastern U.S. on Thursday, especially
northern and central Florida and along the Southeast U.S. coast. 
Meanwhile, a soaking rain is expected to stretch northward from the low
pressure center near the Arkansas-Missouri border through Minnesota
tonight, gradually expanding eastward into the Ohio Valley on Thursday.

By Friday, an anomalously large low pressure system is forecast to engulf
much of the eastern U.S. while pulling in abundant moisture from the
Atlantic.  It appears that the interior Mid-Atlantic into the central
Appalachians will be under the highest threat of heavy rain on Friday as
deep layer moisture from the Atlantic interacts with local terrain ahead
of the low pressure system approaching from the southwest.  Additional
heavy rainfall is also possible across the lower Great Lakes while an
expansive area of rain covers much of the Midwest, Ohio and Tennessee
Valleys and down into the interior Deep South on Friday.  Some locations
in the lower to mid-Mississippi Valley could see the barometer dipping to
record low levels for the month of October Thursday night as the center of
the anomalous low moves across.  Below average high temperatures will
filter into the Mississippi Valley and then into the Southeast on the
backside of the anomalous low.

An active frontal system with multiple low pressure centers will bring
more wet weather to the Pacific Northwest through Friday.  Heavy snow will
impact the peaks of the northern Cascades while lower elevations receive
rain showers over the next couple of days.  Critical Fire Weather is
forecast for parts of the Southern Plains into tonight and Thursday. 
Areas untouched by the ongoing rainfall and severe weather, eastern New
Mexico and south Texas, will be especially susceptible to fire weather due
to dry conditions and high surface wind speeds on the order of 15-25 mph.

Kong


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