537
FXUS02 KWNH 160801
PREEPD

Preliminary Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
300 AM EST Sun Nov 16 2025

Valid 12Z Wed Nov 19 2025 - 12Z Sun Nov 23 2025


...South-central U.S. Heavy Rain/Runoff Threat mid-late week...



...Guidance/Predictability Assessment...

The WPC medium range product suite was primarily derived from a
composite blend of reasonably well clustered recent guidance of
the GFS/ECMWF/Canadian valid for Wednesday/Thursday in a pattern
with seemingly above normal predictability and ensemble/machine
learning support and good WPC continuity overall. The extent of
later week southern stream upper trough/system digging along/off
the West Coast becomes more varied in guidance the last few runs
uncharacteristically showing the ECMWF on the more progressive side
of the full envelope of solutions and the GFS on the less
progressive side. The Canadian seems to offer a solution closer to
the middle, more in line with the GEFS/ECMWF/Canadian ensemble
means and WPC continuity along with the National Blend of Models.

...Weather/Hazards Highlights...

Ample upper trough energy and organized precipitation set to dig
through the West Coast within an emerging southern stream flow over
the next few days will spread across the Great basin/Southwest
midweek to include some enhanced mountain snows. Mid-later week
downstream system progression and lead moisture and instability
return flow genesis into wavy fronts over the south-central to
eastern U.S. and meso-scale features should lead to emergence of a
growing area of moderate to heavy rains and strong thunderstorms
over the south-central U.S., along with eastward progression later
week into the weekend. Accordingly, there is a WPC Day 4/Wednesday
Excessive Rainfall Outlook Marginal Risk area for the south-
central U.S. and a Day 5/Thursday Slight Risk area was introduced
there given cumulative heavy convective/repeat rain potential.

Another digging east Pacific system may offer some enhanced
precipitation chances to the West Coast states Thursday/Friday
along with closed low potential offshore and to the Southwest next
weekend along with uncertain organized precipitation to monitor.

Pre-frontal temperatures will be much warmer than average for much
of the south-central/southern U.S. into this period to include
some record temperatures upwards to 10-20 degrees above normal.
This translates to highs commonly into the 80s, with some warming
shifting to the East late week/weekend. Meanwhile, rounds of
troughing in California to the West/Southwest will lead to below
average highs this week about 5-10+ degrees below climatology.

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














$$