Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
253 PM EST Thu Nov 20 2025

Valid 12Z Sun Nov 23 2025 - 12Z Thu Nov 27 2025


...Heavy Rain Threat for the Southern Plains and Lower Mississippi
Valley on Sunday and Monday...

...Overview...

A strong closed upper low will move across the Southwest this
weekend and into the south-Central U.S. early next week. Southerly
flow ahead of the low will bring warm, moist air into the southern
Plains and Lower Mississippi Valley, which will support a heavy
rain threat across these regions on Sunday and Monday. The system
will continue to move east-northeast on Tuesday, expanding
moderate precipitation chances into the Ohio and Tennessee Valleys,
Mid-Atlantic, and Northeast. Meanwhile, a couple of upper level
troughs will swing across the northern tier of the nation in more
progressive flow, resulting in periods of precipitation from the
Northwest to the Northeast, with heavy snow potential in the higher
elevations of the Cascades and northern Rockies.


...Guidance/Predictability Assessment...

Models continue to show good agreement on the overall synoptic
scale pattern through the medium range period. There are still some
differences in the details of individual systems, mainly in the
second half of the period. The most uncertainty surrounds the
evolution of a low pressure system moving across the Great lakes
and Northeast mid-to-late next week and the timing of a trough
approaching the Northwest, both of which will affect precipitation
amounts and location.

Given good agreement, a near even blend of the latest runs of the
deterministic GFS/ECMWF/CMC/UKMET provided a good starting point
for the afternoon forecast. Ensemble means from the GEFS/ECENS/CMCE
were added in increasing amounts through the second half of the
period to help smooth out model differences.


...Weather/Hazards Highlights...

A low pressure system will bring widespread light to moderate
precipitation to the Southwest this weekend, then the system will
push into the south-Central U.S. early next week. Warm, moist air
will support a heavy rainfall threat across the southern Plains
and Lower Mississippi Valley Sunday into Monday, and there are
signals that this may be a significant event. There is a Slight
Risk of excessive rainfall for the southern Plains on Sunday and
into the Lower Mississippi Valley on Monday. This system will track
east-northeast, spreading precipitation to the east-Central and
eastern U.S. through Tuesday.

Periods of precipitation will also be possible across the northern
tier of the nation as a low pressure system tracks along the
U.S./Canada border. This system will likely also bring gusty winds
to the northern/central Rockies and Plains early next week.
Another round of precipitation is forecast across the Northwest
mid-week as an upper trough pushes onshore from the Pacific, and
there will be potential for heavy snow in the higher elevations of
the Cascades and northern Rockies.

Pre-frontal temperatures will be warmer than average for much of
the Central and eastern U.S. this weekend into early next week.
Much above average temperatures are forecast for the South and
Southeast this weekend where a handful of record high temperatures
will be possible. Meanwhile, California and the West/Southwest
will see below average highs underneath the closed upper low. Mid-
next week, below normal temperatures will also spread across the
Central U.S. in the wake of a strong cold frontal passage.


Dolan/Schichtel


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