Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
330 PM EDT Fri Jun 5 2026
Day 2
Valid 12Z Sat Jun 06 2026 - 12Z Sun Jun 07 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL ACROSS PORTIONS OF
THE SOUTHERN PLAINS TO MISSISSIPPI VALLEY AND ALONG THE CENTRAL
GULF COAST...

20Z Update...

...Central Gulf Coast...

Both the 12Z HREF/REFS provided enough confidence to add a Slight
Risk along the central Gulf Coast centered from southeastern
Louisiana to coastal Alabama. Guidance shows a fetch of tropical
moisture behind a northward-moving low-level wave that will push
PWs upward of 2.25 inches (+2.5 std dev) -- supporting heavy rates.
Raising the threat for heavy accumulations and excessive rainfall
is the potential for training storms. The introduced Slight Risk
area reflects the area where both the HREF/REFS show high
probabilities for amounts over 3 inches.

Elsewhere, made minor adjustments based on the HREF/REFS.

Pereira

Previous Discussion...

...Southern Plains/Mississippi Valley...

The meteorological setup on Saturday across the south-central U.S.
will be similar to Friday, through with the compact upper low
gradually tracking north across the southern half of the Plains.
The continued enhanced moisture and instability will yield an
environment favorable for convection with intense rain rates
causing flash flooding concerns. Areas farther north into Oklahoma
should see stronger forcing, while the low level jet could be
maximized farther south into Texas. Thus covered all this area with
a Slight Risk. REFS probabilities (which extend through the Day 2
period) show scattered instances of QPF potentially exceeding FFG.
Smaller scale boundaries leftover from thunderstorms on previous
days could provide areas of focus that would likely be unclear
before the near term.


...Ohio Valley...

The northern stream shortwave is forecast to push through the Great
Lakes/Ohio Valley and Northeast on Saturday, with a frontal system
ahead of it. The front should lay west to east across the Ohio
Valley, so scattered storms could train and cause isolated flash
flooding. The Northeast can also expect some convection, but likely
progressive enough to limit flash flood potential to below a
Marginal. In this ERO issuance, connected the Plains and Ohio
Valley Marginal Risks together. There is some potential for storms
back into northern Missouri and vicinity, which could be very wet
after multiple rounds of convection, so wanted to cover that area.


Tate


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