Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
426 AM EDT Thu Jun 18 2026
Day 2
Valid 12Z Fri Jun 19 2026 - 12Z Sat Jun 20 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR SOUTHERN
ALABAMA AND ADJACENT AREAS...

...Southeast...

While the plume of extreme moisture associated with the remnants of
Arthur will be exiting the Carolina coast at the start of the
period, deep tropical moisture will remain entrenched over much of
the Southeast on Friday. A cold front that tracked over the Ohio
Valley on Day 1/Thursday will continue edging southward into the
Southeast, bringing much drier air and relief to areas behind it.
Unfortunately ahead of it, the air mass will remain soupy. The
moisture off the Gulf will have turned eastward along the front on
Friday, which will do a couple things: 1) It will not prevent the
front from making more southward progress, as opposed to a
southerly low level jet which would actively work against a
southward moving front. 2) It will create a more unidirectional
wind flow through the depth of the atmosphere, which will support
faster-moving, but training storms along the front. In addition to
any MCSs which could form in the soupy air mass early in the
morning, potentially multiple lines of storms will track
southeastward along the front into the area that just was hit with
Arthur's remnants the previous day. Thus, the Moderate Risk for
this area remains in effect. Expected rainfall for most areas will
generally stay between 1-3 inches on average, so the rainfall
amounts expected on Friday will pale in comparison to today.
However, given the expected flooding that will very much still be
ongoing on Friday, the addition of 1-3 inches of rain with locally
higher amounts where storm training persists longest over these
same areas still raised the flooding threat in the area to the
Moderate Risk category. Changes in where the heaviest rains
today/Day 1 occur may result in shifts of the Moderate Risk,
particularly if the heaviest expected rains occur further south and
west into Mississippi and eastern Louisiana. A few of the CAMs
models are hinting at that possibility.

...Southern Plains...

Across a large swath of Texas on Friday, multiple MCSs may impact
much of the state. On Friday morning, lingering MCSs from Oklahoma
and the Slight Risk on Day 1 may be ongoing into north-central
Texas Friday morning, including into the Metroplex. Widely
scattered instances of flash flooding will be possible with that.
More coverage of storms are expected Friday night. The typical
strengthening MCS will advect extreme instability and moisture over
all of the eastern half of the state. As storms form and organize
into MCSs, the potential for additional instances of flash flooding
will increase. There is considerable uncertainty as to where they
form and how they track, so a large swath of eastern Texas was
included in a Slight Risk, especially down towards San Antonio and
Houston, which have been impacted with heavy rains in recent days,
and soils remain wetter than normal.

Wegman

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