Short Range Forecast Discussion
NWS Weather Prediction Center College Park MD
241 PM EST Wed Nov 29 2023
Valid 00Z Thu Nov 30 2023 - 00Z Sat Dec 02 2023
...Milder temperatures over the Plains and Midwest to push east toward the
East Coast for the remainder of the week...
...New storm system to bring threat of severe thunderstorms and heavy rain
across the Arklatex and the Lower Mississippi Valley on Thursday...
...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...
Cold air and below normal temperatures lingering along the East Coast
today will give way to a warming trend for the next couple of days as
milder temperatures already advancing across many areas of the Plains and
Midwest advances off to the east. However, there will be one more night of
sub-freezing temperatures that will impact portions of the Southeast with
a focus on southeast Alabama, the Florida Panhandle, the northern Florida
Peninsula, and southern Georgia where Freeze Warnings are in effect. Once
again there should be precautions taken to protect sensitive vegetation as
low temperatures by Thursday morning are expected to drop as cold as the
upper 20s and low 30s.
On Thursday and heading into Friday, one of the bigger stories will be the
increasing threat of severe weather and even some concerns for localized
flash flooding as a storm system crossing the Southwest tonight ejects out
across the southern Plains and takes aim on the Lower Mississippi Valley
and Mid-South. In conjunction with the arrival of multiple cold fronts,
there will be the development of low pressure near the Red River Valley by
late Thursday which will open the door for a rather significant northward
surge of moisture and instability from the Gulf of Mexico heading through
Thursday evening and into Thursday night. This will set the stage for
rather widespread coverage of showers and thunderstorms across the
Arklatex and the Lower Mississippi Valley, with adjacent areas of the
Middle Mississippi Valley and Mid-South also likely to see areas of
moderate to locally heavy rainfall.
Severe weather is becoming more of a concern in particular over areas of
southeast Texas on Thursday, and the Storm Prediction Center has depicted
an Enhanced Risk of severe weather across this region with concerns for a
few tornadoes. Some of the severe weather threat may spread east into
areas of southwest Louisiana heading into Thursday night. Regarding the
rainfall threat, locally a few inches of rain will be possible, and while
most of the rain should be beneficial in nature across the broader
Arklatex and Lower Mississippi Valley, some localized flash flooding
concerns and especially around the more urbanized areas of southeast Texas
and southwest Louisiana, will be possible. The Weather Prediction Center
currently has a Marginal Risk of excessive rainfall depicted across these
areas.
On Friday, this storm system will cross through the Mid-South and lift
into the Lower Ohio Valley. A fairly widespread area of moderate to
locally heavy rain will still accompany the low track, but the heaviest
rains should stay confined closer to the central Gulf Coast where better
moisture and instability will help concentrate more of the thunderstorm
activity. A Marginal Risk of both severe weather and flash flooding is
depicted across these areas respectfully from the Storm Prediction Center
and Weather Prediction Center.
Elsewhere, an active and wet weather pattern will begin to ensue across
the Pacific Northwest on Thursday and Friday as atmospheric river activity
arrives in off the Pacific Ocean in conjunction with a couple of cold
fronts. Strengthening onshore flow and moisture transport will set the
stage for areas of heavy rainfall across the coastal ranges, with locally
a few inches of rain expected. However, over the higher elevations of the
Cascades, heavy snowfall is expected, and some areas may see as much as 1
to 2 feet of new snow by late Friday with more on the way heading into the
weekend.
Orrison
Graphics available at
https://www.wpc.ncep.noaa.gov/basicwx/basicwx_ndfd.php