Extended Forecast Discussion
NWS Weather Prediction Center College Park MD
332 AM EDT Sat Oct 17 2026

Valid 12Z Mon Oct 19 2026 - 12Z Fri Oct 23 2026


...A nor'easter could bring prolonged impacts to coastal
communities along the East Coast...


...Overview...

A developing nor'easter is expected to bring wind, rain and coastal
flooding impacts to the East Coast next week. A cutoff low will
bring excessive rainfall concerns to the Four Corners mid-to-late
next week. A downstream ridge will amplify and promote above
average temperatures across the Central U.S..


...Guidance/Predictability Assessment...

There's a consistent signal for closed mid-level lows to develop
along the East and West Coasts, while a ridge amplifies over the
Central U.S.. Models continue to teeter back and forth with the
positioning of the East Coast low, with the latest model runs
suggesting a day 3 location slightly farther away from the Mid-
Atlantic Coast.

Clustering analysis indicates that the timing of the Western U.S.
trough/cut-off low is the main area of uncertainty across the CONUS
during the medium range period. The Euro and Euro AIFS are favored
in the blend throughout the medium range given their decent run-
to-run consistency and good clustering later in the period.
deterministic GFS incorporates well with the Euro consensus through
day 5. The ensemble means are favored on days 6 and 7 to help
mitigate spread in solutions regarding the East Coast trough and
Western U.S. trough.


...Weather/Hazards Highlights...

A nor'easter is expected to bring strong winds, potentially heavy
rain and coastal flooding to the Mid-Atlantic and Northeast Coasts
this week. The mid-latitude cyclone responsible for these hazards
is forecast to intensify well off the Carolina Coast tonight before
drifting back toward the mainland on Monday. Persistent onshore
flow should generate strong winds with gusts exceeding 40 kts
possible along the immediate coastline. Beach erosion is also
likely from the aforementioned strong onshore flow. Please refer to
WPC's Key Messages on our website for more information:
www.wpc.ncep.noaa.gov.


An upper ridge, aided by an amplifying upstream pattern and
approaching embedded shortwave energy, will support broad southerly
flow and above average temperatures across the central U.S. next
week. The embedded shortwave doesn't carry a threat of producing
any precipitation.

A shortwave passing south of the Gulf of Alaska is forecast to
dig/amplify into a cut-off low over the eastern Pacific just off
the West Coast midweek. The depth and speed of this system will
determine how much moisture it can pull into the region. The latest
trends suggest an increasing likelihood for anomalous moisture to
be pulled into the West. This moisture will then interact with a
strong cold front and produce scattered to isolated thunderstorms
over portions of the Four Corners. Heavy rainfall may occur as well
with some Extreme Forecast Index shift of tail signals showing up
across the Southwest by next Tuesday night and continuing through
Thursday. Some high elevation snowfall can't be ruled out for
parts of the Intermountain West and Sierra Nevada mid-week.

Another shortwave diving south through British Columbia will send a
cold front into the Northwest mid-to-late next week. This system
could generate high elevation snow for portions of the Northern
Rockies/Intermountain West late next week.


Kebede


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