Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
334 AM EDT Thu May 28 2026
Day 2
Valid 12Z Fri May 29 2026 - 12Z Sat May 30 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL ACROSS PARTS OF
THE NORTHERN ROCKIES AS WELL AS MUCH OF THE SOUTHEAST TO MIDDLE
MISSISSIPPI VALLEY...

...Eastern Washington to Northern Rockies...

A marginal risk is in place across far northeast Washington to
northwest Montana due to an increase in the heavy rainfall signal
for this period as the upper low over the West on Day 1, pivots
slightly northeastward, placing this region in an area with better
upper forcing and advection of moisture. The presence of anomalous
moisture and some instability may present a threat for localized
heavy rainfall and flash flooding, especially for burn scar
locations within this region.

...Middle Mississippi Valley to the Southeast...

Strong Canadian high pressure pressing in from the north will
allow for a slow moving cold front to press south over the course
of Thursday into Friday with convection likely to spawn along and
ahead of the front and dry air advecting behind the front leading
to a quick cutoff of activity. The front will arc back into the
Tennessee Valley to Middle Mississippi Valley, supported by the
persistent troughing over the south-central Plains. A moist and
unstable environment near and south of this front will support
scattered convection, with some heavier cells likely within the
pattern. It is still too hard to pick out any discernible areas of
interest, so maintained a very broad marginal risk over this area
which is quite wet and will continue to be in the Day 1 period.

Santorelli


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