Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
429 AM EDT Fri May 29 2026
Day 2
Valid 12Z Sat May 30 2026 - 12Z Sun May 31 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS THE
NORTHERN ROCKIES TO HIGH PLAINS AND THE SOUTHEAST...

...Southeast...

Latest numerical guidance has shifted a majority of the rainfall
eastward enough compared with previous runs to preclude an upgrade
to a Slight risk. In addition...the spread of model
guidance both in terms of placement and amounts precluded an
upgrade. As mentioned previously...some of the region, especially
western parts of South Carolina and into the Appalachians, has
been very wet as of late and is well primed, so may by more
vulnerable to flooding concerns.

...Northern Rockies to High Plains...

The upper level low over the West during the Day 1 period will
weaken and shift northeastward, moving over the Northern Rockies to
High Plains region on Saturday. Moisture anomalies will continue
to be in the 90-90th percentile, supporting moderate to heavy
rainfall, with widespread QPF greater than 0.5-1" likely across
western and central Montana. There may not be a lot of instability
to work with, so any flood or flash flood threats should be mainly
localized with particular attention to burn scar locations. A
fairly broad marginal risk remained in place across much of
western and central Montana, into parts of northern Wyoming as
well.

Bann

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