491
FXUS02 KWBC 131849
PMDEPD

Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
149 PM EST Thu Nov 13 2025

Valid 12Z Sun Nov 16 2025 - 12Z Thu Nov 20 2025


...Overview...

Multiple rounds of troughing are forecast to move through the
western U.S. next week, bringing periodic rain and higher elevation
snow. A surface low moving through and exiting the Northeast
Sunday could bring some wintry precipitation behind it. Then a low
pressure/frontal system will spread some precipitation (mostly
rain) to the Mississippi and Ohio Valley Monday and stretching
across the south-central U.S. into the Appalachians Tuesday as the
front starts to stall. Increasing lift aloft could yield heavy
rainfall for the southern Plains/Lower Mississippi Valley into
midweek, which could bring the risk for flooding and severe
weather. Temperatures should be warmer than average for the central
U.S. Sunday, but become more limited to the southeastern quadrant
of the lower 48 during the workweek, to the south of the stalling
west- east oriented front.


...Guidance/Predictability Assessment...

The period starts with the models showing overall agreement of the
major features with the pronounced trough over the Great Lakes
with an upper-level low situated over the Northeast U.S., a ridging
pattern over the High Plains, and a closed low over the Southwest
U.S. There is some slight differences with the placement of the
closed low in the Southwest U.S. and eventual progression as an
open wave into the Plains shown in the previous runs of the GFS.
Towards mid- week, another outlier feature that the GFS showed was
an acceleration of precipitation towards the east with this system,
while the ECMWF and ECens mean, showed slower progression.
Therefore, most of the forecast for the first half of the period
put more weight on the ECMWF. Towards the middle portion of the
period, the guidance starts to show variability with an upstream
trough approaching the western U.S. with a potential for a split
between a northern and southern stream. The CMC starts to show more
variability in the evolution of these features with the southern
stream cutting off compared to the ECMWF and GFS. The ECMWF and GFS
showed the southern stream wave advancing eastward towards the
south Central U.S. with another upstream trough following quickly
behind, towards the West Coast. These model forecasts, along with
the GEFS and ECens mean showed more alignment with the overall
upper level pattern and progressive wave structure.

The WPC forecast was based on a mix of the ECMWF, GFS, and CMC for
the first portion of the period, as models show agreement among
the major features. Towards the mid to late period, solutions begin
to differ, influencing the forecast towards introducing more of
the ECens and GEFS mean, with slowly phasing out CMC.


...Weather/Hazards Highlights...

As the period begins Sunday, the initial southern stream closed
low will lift across the interior West. As it does so, it should
gradually lose the deeper moisture connection, but widespread
precipitation is likely across the West. Modest precipitation
(mostly rain even into parts of the Mogollon Rim) is forecast to
march across Arizona with the associated cold front, but the quick
movement and less significant moisture anomalies should keep
flooding potential lower than Marginal ERO levels. Farther north
into the Intermountain West, snow is likely in the higher
elevations, with some heavy amounts possible in the San Juans and
central Rockies. Another round of troughing should reach the West
Coast later Sunday into Monday and promote additional
precipitation. Any atmospheric river accompanying the frontal
system moving into the West should be much weaker than the system
during the short range period. However, plan to have a Marginal
Risk in the ERO for Day 5/Monday for the Transverse Ranges of
southern California, as this area tends to be sensitive due to
terrain enhancement of precipitation and burn scars, and heavy rain
is expected there just a day or two before. Continue to monitor
for changes to the forecast. Rain and higher elevation snow will
continue tracking east into Tuesday, and yet another possible upper
trough may bring additional precipitation to the West Coast by
Wednesday. Precipitation could be moderate or heavy at times.

Precipitation chances are likely across the Northeast Sunday into
Monday with and behind a relatively deep surface low pressure
system pulling away. Light precipitation is also forecast with
westerly flow over the Appalachians. Gusty winds are possible in
these areas as well.

A frontal system emerging into the central U.S. on Monday should
start to spread rain into the north-central Plains, Middle
Mississippi Valley, and Ohio Valley, with perhaps some snow/mix on
the northern edge of the precipitation shield. The front is
currently forecast to stretch across the southern Plains to
Mississippi Valley and Ohio/Tennessee Valley on Tuesday, bringing
rain chances there and into the southern/central Appalachians and
Mid-Atlantic. Initial forecasts show that as another front
approaches the High Plains midweek along with troughing aloft,
deeper moisture may reach the stalling front and produce heavy
rainfall across the south-central U.S. along with potential
thunderstorms. Several models indicate the potential for several
inches of rain, which can bring a flood risk if this trend
continues. There is also an increasing concern for severe weather
beginning Wednesday. Continue to monitor for changes to the
forecasts as the details remain uncertain.

Temperatures are forecast to be warmer than average for much of
the central to southern U.S. on Sunday. Highs in the 60s should
reach the central High Plains, around 10-15 degrees above average,
while highs in the 80s will be common across Texas, Louisiana, and
Florida with 70s across the rest of the Southeast. The southern
Plains to Southeast can expect temperatures to remain warmer than
average through much of next week to the south of the west-east
oriented front. There are some model differences in frontal
position that will be the dividing line between near normal to
above normal conditions, so the temperature forecasts will continue
to be refined. Meanwhile the rounds of troughing in California to
the Southwest will lead to below average highs there most days.


Oudit/Tate


Additional 3-7 Day Hazard information can be found on the WPC
medium range hazards outlook chart at:
https://www.wpc.ncep.noaa.gov/threats/threats.php

WPC medium range 500mb heights, surface systems, weather grids,
quantitative precipitation forecast (QPF), excessive rainfall
outlook (ERO), winter weather outlook (WWO) probabilities, heat
indices, and Key Messages can be accessed from:

https://www.wpc.ncep.noaa.gov/medr/5dayfcst500_wbg.gif
https://www.wpc.ncep.noaa.gov/medr/5dayfcst_wbg_conus.gif
https://www.wpc.ncep.noaa.gov/5km_grids/5km_gridsbody.html
https://www.wpc.ncep.noaa.gov/qpf/day4-7.shtml
https://www.wpc.ncep.noaa.gov/#page=ero
https://www.wpc.ncep.noaa.gov/wwd/pwpf_d47/pwpf_medr.php?day=4
https://www.wpc.ncep.noaa.gov/heat_index.shtml
https://www.wpc.ncep.noaa.gov/#page=ovw




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