Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
217 AM EDT Thu Oct 29 2026

Valid 12Z Sun Nov 01 2026 - 12Z Thu Nov 05 2026


...Storm system will bring precipitation across the West on Sunday
into Monday and into the central U.S. Monday-Tuesday...


...Overview...

An amplifying trough progressing from western U.S. into the central
U.S. may produce cyclogenesis over the Plains and an expansive
areas of precipitation spreading eastward. Meanwhile, a series of
shortwaves embedded withing a mid-level ridging will support
additional rounds of showers and thunderstorms from the
Mississippi Valley into the Southeast and Ohio Valley. By early
next week, the frontal system moving eastward across central U.S.
will provide a focus for widespread rainfall and gusty winds.


...Guidance/Predictability Assessment...

Models continue to show reasonable agreement on the broad evolution
of the troughing moving eastward into western U.S. and gradually
pushing into central U.S. through the week. The challenge remains
with the timing and degree of phases of the northern-stream energy
dropping southeastward into the West, while the southern-stream
progresses into the Southwest. Furthermore, there is uncertainty
with the timing and speed of the trough and frontal boundary
progression eastward. A slower or more amplified solution would
favor a longer period of rainfall across portions of the central
U.S., while a faster progression would shift the main precipitation
axis east. Additionally, there are differences amongst the models
regarding the shortwave moving across eastern U.S. the beginning
of the period, that will effect sensible weather. The GFS continue
to show a more northward and faster track.

The forecast reflected greater weight on a multi-model blend with
the CMC/ECMWF/GFS and AI-based model solutions, with less weight on
the GFS, for the first portion of the period. Heavier weight
towards
the ensemble means were used for the latter portion of the period.



...Weather/Hazards Highlights...

Across the central and eastern U.S. shortwave disturbances moving
along the ridge may support additional rounds of showers and
thunderstorms from the lower Mississippi Valley into the Southeast
and portions of the Midwest/Ohio Valley on Sunday. A moist low-
level flow from the Gulf combined with increasing mid-level
forcing, may favor periods of organized convection and heavy
rainfall.
WPC Excessive Rainfall Outlook Marginal Risk is in place for
portions of eastern Florida Coast for Sunday and Monday.

The combination of the upper trough extending across western U.S.,
with embedded shortwave energy, and increasing Pacific moisture
will lead to widespread precipitation across portions of
California, Great Basin, Four Corners, and Intermountain West.
Heavy rainfall will be possible in favored low-elevation areas,
particularly where moisture transport becomes enhanced. WPC
Excessive Rainfall Outlook Marginal and embedded Slight Risk areas
are in place for the Southwest and central Plains/Midwest for
Sunday. Furthermore, snow is likely across higher elevations of
the Rockies into Monday, with snow levels dependent on the depth of
the incoming cold air. The trough will continue to progress
eastward into the Plains, with increasing potential for a closed
low developing. Strengthening cyclonic flow aloft will draw Gulf
moisture northward into the Plains and will pool along the eastward
moving frontal boundary, leading to showers and thunderstorms
across much of central U.S. on Monday. Locally heavy rainfall may
be possible along parts of the Mississippi Valley, where deep
moisture overlaps with mid- level forcing. WPC has expanded a
Marginal Risk for Excessive Rainfall for portions of the
Mississippi Valley and Plains for Monday. Additionally, strong
pressure gradients around the deepening surface low may bring gusty
winds across portions of the Plains on Monday. Widespread showers
and thunderstorms will push eastward, as the system moves further
into eastern U.S. through Wednesday.

Behind the system, cooler and drier air should begin to spread into
portions of central U.S. Temperatures will trend towards seasonal
values across the Plains, while the eastern states may remain
relatively mild ahead of the advancing front.



Oudit


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, excessive rainfall outlook,
winter weather outlook probabilities, heat indices and Key Messages
are at:

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