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FOUS30 KWBC 160844
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
444 AM EDT Tue Jul 16 2024

Day 1
Valid 12Z Tue Jul 16 2024 - 12Z Wed Jul 17 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FROM PARTS OF THE
CENTRAL HIGH PLAINS TO THE OHIO VALLEY...

...Mid-Mississippi and Ohio Valleys...
Strengthening southwesterly flow ahead a shortwave moving across
Kansas will support deepening moisture ahead of a cold front
sliding southeast into the mid Mississippi Valley this morning and
the lower Ohio Valley later today. Persistent inflow into this
slow-moving boundary along with favorable forcing aloft is
expected to support periods of training storms, with areas of heavy
rainfall likely, especially from central and southern Missouri
eastward into the lower Ohio Valley. Excessive rainfall is
especially a concern from central and southern Missouri through
southern Illinois to the western Indiana and Kentucky border, where
the 00Z HREF is showing high neighborhood probabilities for
accumulations of 3 inches or more through the period.

...Central Plains...
Moist upslope flow behind a cold front settling south through the
central Plains will support storms developing over the high terrain
before these storms spread east into the Plains during the
evening. Merging storms along with increasing organization ahead of
a shortwave digging southeast through the Plains is expected to
support locally heavy amounts from southeastern Colorado through
southwestern Kansas and northwestern Oklahoma, where the HREF is
also showing some notable probabilities for 3 inches or more.

...Upper Ohio Valley to the Northeast...
Ample moisture ahead of an amplifying upper trough over the Great
Lakes and its associated cold front will fuel additional storms
later today. Overall, storms that develop are expected to be
progressive in nature. However, intense rainfall rates may produce
isolated runoff concerns.

...Southwest...
An upper high sitting over the Four Corners will allow moisture to
funnel across the region, with an expansion of convective activity
expected today, bringing the risk for isolated heavy amounts and
flash flooding to a greater portion of Arizona and New Mexico.

Pereira

Day 2
Valid 12Z Wed Jul 17 2024 - 12Z Thu Jul 18 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS
COLORADO AND NEW MEXICO, AND THE ARKANSAS AND RED RIVER BASINS TO
MID-SOUTH...

....Southwest to the Central to southern Rockies and High
Plains...
As the previously noted front continues to slide to the
south through the Plains, increasing moisture afforded by low-
level easterly flow will support an increasing threat for locally
heavy rainfall and flash flooding concerns. Ample moisture along
with increasing lift will support storms capable of producing heavy
rainfall rates, that will develop and drop south across the
region. The greater threat continues to center from the Colorado
Sangre de Cristos into the northern and central New Mexico ranges,
where models show some of the better low level inflow and greater
PW anomalies.

Elsewhere, a more typical monsoon pattern will continue, with
diurnal convection generating isolated heavy rainfall and flash
flooding concerns across much of the Southwest.

...Southern Plains to the Northeast...
An upper trough will continue to amplify over the Great Lakes,
pushing a cold front that will extend from the Northeast to the
southern Plains this period further south and east. While locally
heavy rainfall and an isolated threat for heavy rainfall cannot be
ruled out for any area along the front, deeper moisture and
stronger forcing are expected to elevate the threat for some areas.
This includes portions of the Red River and Arkansas basins into
the Mid-South. Deepening moisture and increasing ascent ahead of a
shortwave approaching from the northeast is expected to support
organized heavy rainfall across the region. With plenty of typical
difference in the details, several of the overnight deterministic
models indicate locally heavy amounts of 2-3 inches within the
Slight Risk area.

Pereira

Day 3
Valid 12Z Thu Jul 18 2024 - 12Z Fri Jul 19 2024

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL FOR PORTIONS
SOUTHEASTERN VIRGINIA AND EASTERN NORTH CAROLINA AND THE SOUTHERN
ROCKIES...

...Southern Mid-Atlantic and the Southeast to the lower Mississippi
Valley...
The previously noted cold front will continue to settle further
south and east, bringing heavy rain and the threat for flash
flooding into portions of the southern Mid Atlantic, the Southeast,
and the lower Mississippi Valley. A Slight Risk was maintained
across portions of southeastern Virginia and eastern North
Carolina, where PWs are forecast to increase to ~2.25 inches as the
front settles and begins to stall across the region. This moisture
along with some mid-to-upper level support is expected to fuel
heavy amounts across the region.

Elsewhere, models suggest less organized storms with more isolated
threats for flash flooding further west along the front into the
lower Mississippi Valley.

...Southwest to the central and southern Rockies...
With no significant change to overall pattern expected and plenty
of moisture remaining in place, maintained much of the same outlook
areas from Day 2 into Day 3, including a Slight Risk centered over
north-central New Mexico extending into far south-central Colorado.

Pereira

Day 1 threat area: https://www.wpc.ncep.noaa.gov/qpf/94epoints.txt
Day 2 threat area: https://www.wpc.ncep.noaa.gov/qpf/98epoints.txt
Day 3 threat area: https://www.wpc.ncep.noaa.gov/qpf/99epoints.txt