213
FXUS21 KWNC 141814
PMDTHR
US Hazards Outlook
NWS Climate Prediction Center College Park MD
300 PM EDT September 14 2026

SYNOPSIS: Mid-level high pressure building into much of the central and eastern
contiguous U.S. (CONUS) favors relatively quiet weather over much of the
country during week-2. A stalled frontal system over the Mid-Atlantic and
Southeast could bring heavy precipitation to the area. In the West, continued
chances for enhanced mid-level moisture is favored, potentially bringing heavy
precipitation and possible flooding over portions of the Four Corners and
southern High Plains.

HAZARDS

Slight risk of heavy precipitation for portions of the Southeast, Mid-Atlantic,
and Northeast, Tue-Wed, Sep 22-23.

Slight risk of heavy precipitation for parts of the Southwest, southern
Rockies, and southern High Plains, Tue-Thu, Sep 22-24.

Flooding possible for portions of the Four Corners region.

DETAILED SUMMARY

FOR THURSDAY SEPTEMBER 17 - MONDAY SEPTEMBER 21:
https://www.wpc.ncep.noaa.gov/threats/threats.php

FOR TUESDAY SEPTEMBER 22 - MONDAY SEPTEMBER 28: The GEFS, ECENS and CMCE remain
in good agreement in regards to the evolution of the 500-hPa pattern next week.
A mid-level ridge amplifies over central and eastern Canada during week-2
bringing positive height anomalies back to the central and eastern contiguous
U.S. (CONUS) with time. A longwave trough is forecast upstream over the Gulf of
Alaska and along the West Coast.



There continues to be an elevated chance of heavy precipitation for parts of
the Eastern Seaboard early in the period. A lingering frontal zone is forecast
across the region and southerly return flow could bring enhanced moisture into
the area. The Probabilistic Extremes Tools (PETs) from the GEFS and ECENS both
highlight increased chances for precipitation to exceed the 85th climatological
percentile and 1 inch in this region. Similarly, the uncalibrated guidance
continues to support a heavy precipitation risk. There is stronger agreement
into portions of the Northeast today and combined with recent flooding leaves
the area more susceptible to heavy precipitation. Therefore, a slight risk of
heavy precipitation is posted for Sep 22-23 for parts of the Northeast,
Mid-Atlantic, and Southeast.



Weak troughing and onshore flow is favored near the West Coast along with the
potential for additional tropical moisture from the eastern Pacific. Therefore,
a slight risk of heavy precipitation remains posted (Sep 22-24) over the Four
Corners where uncalibrated tools maintain elevated chances for 3-day
precipitation amounts exceeding a half an inch, and in some locations more than
one inch. Guidance is developing elevated risks of heavy precipitation further
east into western Texas. Therefore, the slight risk has been expanded slightly.
In addition, given the continued indications of potentially heavy precipitation
during the next week or so, a flooding possible hazard remains posted for
portions of the Four Corners. This region is prone to flash flooding and
caution should be exercised near canyons and creek beds.



In Alaska, the previously forecast slight risk of heavy precipitation has timed
off into week-1 and no hazards are currently posted. However, model guidance is
indicating the potential for another low pressure system to move into the Gulf
of Alaska by the middle of week-2. This system may be tied to a recurving
cyclone from the West Pacific and could bring heavy rain and high winds to
parts of Alaska. While uncertainty remains too high for an additional slight
risk, this area will continue to be monitored.



Across the central and eastern Pacific, the National Hurricane Center (NHC) is
currently monitoring Tropical Storm Norbert and Tropical Depression 15-E. Both
Norbert and TD15-E are forecast to continue on a westward track but are
unlikely to strengthen based on the NHC`s current forecasts. Nevertheless,
should these systems or their remnants move towards Hawaii, they could pose an
additional heavy precipitation risk to the state into week-2. Any additional
precipitation may worsen already saturated grounds across parts of Hawaii,
following the impacts associated with TCs Lowell, Moke, and Lala this season.

FORECASTER: Ryan Bolt

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