Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Thu Nov 30 2023

Valid 12Z Thu Nov 30 2023 - 12Z Sat Dec 02 2023

...Storm system to bring threat of severe thunderstorms and heavy rain
from the Southern Plains to the Lower Mississippi Valley on Thursday,
spreading further into the Southeast Friday...

...Areas of light to moderate precipitation expected from the Central
Plains to the interior Northeast, with a wintry mix possible for some
locations...

...Atmospheric river activity arriving across the Pacific Northwest by the
end of the week will bring heavy rain to the coastal ranges, and heavy
snowfall to the Cascades...

...Locally heavy snowfall possible for higher mountain elevations in the
Four Corners region...

An upper-level shortwave over the Southwest will move over the Southern
Plains Thursday, helping to better organize/strengthen a surface frontal
system and bring increasing storm chances from eastern portions of the
Southern Plains to the Lower Mississippi Valley. Very moist southerly
return flow from the Gulf will result in a threat for both severe weather
and some flash flooding. The best chance for severe weather Thursday will
be in southeastern Texas where strengthening wind fields will overspread
the more buoyant air close to the Gulf Coast. The Storm Prediction Center
has issued an Enhanced Risk of severe weather (level 3/5) for the threat
of a few tornadoes. Additionally, some very heavy downpours will be
possible, with a Slight Risk of Excessive Rainfall now in place for the
greater Houston area east through southwestern Louisiana where the
greatest chance for a few instances of flash flooding is expected. A more
isolated threat for severe weather and flash flooding will exist further
north into the Arklatex and Lower Mississippi Valley. Storm chances will
shift slowly eastward into the Southeast and along the central Gulf coast
Thursday, with a continued risk of a couple isolated instances of severe
weather and flash flooding.

Additional light to moderate precipitation is expected to the north of the
surface low track, stretching from the Central Plains/Middle Mississippi
Valley Thursday into the Great Lakes, Ohio Valley, and interior Northeast
Friday. Some snow will likely mix in to the north of a quasi-stationary
boundary draped through the region, most likely for portions of the
Central Plains Thursday and from the Great Lakes into the interior
Northeast Friday. Some light accumulations of 1-2" will be possible. 

An active pattern of Atmospheric River activity looks to set up along the
West Coast through at least this weekend with a series of shortwaves and
influx of moisture overspreading the Pacific Northwest/northern
California. Coastal/lower elevations will see moderate to locally heavy
rain, with the heavier rainfall more likely Friday and then into the
weekend. The flood threat currently looks low with this initial rainfall,
though will likely slowly increase as antecedent conditions become wetter.
Heavy snowfall is forecast for higher elevations in the Cascades, with
totals exceeding a foot through the end of the period. Moisture will also
spread inland through the Great Basin and Northern Rockies, with a
rain/snow mix for lower elevations and moderate to heavy snow in the
regional mountain ranges. Any accumulations should be limited for the
lower elevations, but some of the mountains could see 6-12", with locally
higher amounts. A rain/snow mix at lower elevations and moderate to heavy
snow for higher mountain locations will also continue in the Four Corners
region through Friday as the upper-level wave currently over the Southwest
departs but the pattern remains active with shortwaves dropping southward
from the Northwest.

Elsewhere, milder temperatures are forecast to return to the East Coast
after several chilly days. Conditions will be dry Thursday but rain
chances will increase by late Friday as the storm system to the west
approaches. Temperatures will be near average with dry conditions from the
Northern Plains to the Upper Midwest.
 
Putnam

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