Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
429 AM EDT Sat Sep 26 2026
Day 2
Valid 12Z Sun Sep 27 2026 - 12Z Mon Sep 28 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PARTS OF THE
NORTHEAST...

...Northeast...

The potent nor'easter will begin to weaken as it lingers in the
vicinity of the northern Mid-Atlantic coast. How far inland, if at
all, the storm drifts will help dictate how far beyond the coastal
regions its associated heavy rains will reach. Heavy rainfall is
expected to linger overhead, leading to an additional 1-2.5 inches
of rainfall over much of the same area. These rains will overlap
areas impacted during the Day 1 period thus maintaining an elevated
threat for excessive rainfall and flash flooding concerns. A Slight
Risk remains in effect from coastal New Jersey to eastern
Massachuesetts with a Marginal from southern New Jersey to
southern Maine.

...Southwest...

Increasing southwesterly flow ahead of an amplifying trough
digging south across California will begin to tap moisture and mid-
to-upper level energy, supporting an increase in shower and
thunderstorm activity and the potential for localized areas of
flash flooding from Southern California into the Southwest.

...Northern Plains...

A Marginal Risk area was raised for portions of the Northern Plains
as a northern stream trough exits the Rockies and begins to tap
into moisture over the plains. Rainfall rates exceeding 0.50
inch/hour may lead to isolated instances of flash flooding across
the area.

Campbell/Pereira


Day 2 threat area: www.wpc.ncep.noaa.gov/qpf/98epoints.txt