Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
1000 AM EST Mon Nov 2 2026

Day 1
Valid 1456Z Mon Nov 02 2026 - 12Z Tue Nov 03 2026

...THERE IS A MODERATE RISK OF EXCESSIVE RAINFALL FOR AREAS BETWEEN
MELBOURNE AND PORT ST. LUCIE, FLORIDA...

...Florida...

15Z Special: A targeted MDT risk has been added in coordination
with the Melbourne WFO due to significant rainfall and high-end
impacts occurring from a convergent band of heavy precipitation
over the east-central FL coast. Rainfall totals of 5-15" have
fallen in a narrow corridor between Melbourne down to just north of
Fort Pierce leading to widespread flash flooding in this zone,
especially just south of Melbourne proper. More on this setup will
be included in the official 16z update.

Kleebauer

..Previous Discussion..

While PWs are forecast to drop off some, persistent easterly flow
will continue to support an anomalously moist airmass -- fueling
another day of potentially heavy amounts and flash flooding along
the eastern peninsula, especially from the Space Coast down to
southeastern Florida. A Slight Risk was maintained along this
area, highlighting where both the HREF and REFS indicate localized
amounts over 3 inches are likely today.

...Midwest/Plains...

A highly-amplified and multi-stream upper trough is forecast to
move east of the Rockies into the Plains today, producing
widespread precipitation across the central U.S. A well-defined
shortwave within the base of the trough will move from the Four
Corners this morning, into the central and southern Plains by this
evening. The potential for heavy rain is expected to increase this
evening across portions of the southern and central Plains,
especially from eastern Oklahoma and Kansas into western Missouri
as a 40-50+ kt southwesterly low level jet develops ahead of the
wave, supporting strong moisture advection into a region of
increasing ascent. Showers and storms are expected to develop with
the potential for heavy rates increasing as PWs increase to ~1.75
inches and right-entrance region upper jet forcing supports large-
scale ascent. Hi-res guidance indicates that elevated storms can be
expected during the late afternoon across portions of eastern
Oklahoma into the lower Missouri Valley before a more robust line
of storms develops and advances east ahead of a sweeping cold
front. In addition to the potential for more than one round of
storms, a period of training convection may elevate the risk for
localized heavy amounts and flash flooding. A Slight Risk was added
where both the HREF and REFS show high neighborhood probabilities
for accumulations over 3 inches. Both also showed neighborhood
probabilities for amounts exceeding 3-hr FFGs increasing into the
20-30+ percent range across portions of the area during 0-6Z
Tuesday timeframe.

Farther to the north, a Marginal Risk covering portions of the
northern Plains and upper Midwest was maintained. Widespread
coverage of 1-2 inch amounts across parts of the Dakotas and
Minnesota is forecast. However, not expecting any widespread flash
flooding concerns as limited instability will keep rainfall rates
in check.

Pereira


Day 2
Valid 12Z Tue Nov 03 2026 - 12Z Wed Nov 04 2026

...THERE IS A SLIGHT RISK OF EXCESSIVE RAINFALL PORTIONS OF MID-
SOUTH...

...Lower and Mid-Mississippi Valley...

The general consensus of the hi-res guidance shows that storms
developing late Monday will remain ongoing along an advancing cold
front extending from the mid Mississippi Valley back into eastern
Texas Tuesday morning. There is some indication in the guidance
that heavy rates and continued southwest-northeast training may
elevate the threat for heavy amounts and flash flooding from the
Ozark region into southeastern Missouri. This suggests an upgrade
may need to be considered at some point, but for now maintained the
outlook at just a Marginal Risk. Farther east, a Slight Risk
centered over the Mid-South was maintained -- where deep moisture
and favorable upper jet forcing are expected to support
re-intensifying storms capable of producing heavy rainfall rates.
The previous Slight Risk was largely maintained, but adjusted a
little to reflect the REFS high neighborhood probabilities for
2-3+ inches across this area.

...Florida...

Easterly flow will weaken this period; however, with anomalous
moisture remaining in place, cannot rule out additional localized
heavy rainfall amounts resulting in at least isolated flash
flooding concerns, especially in urbanized locations and areas
previously inundated with heavy rains.

Pereira


Day 3
Valid 12Z Wed Nov 04 2026 - 12Z Thu Nov 05 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM THE
TENNESSEE AND LOWER OH VALLEYS TO THE SOUTHERN AND CENTRAL
APPALACHIANS...

Activity developing late Tuesday may continue into the early part
of the period, with a ribbon of deep moisture and favorable upper
jet forcing contributing to additional heavy rates and possible
flash flooding across parts of the Tennessee and lower Ohio valley
early on. Storms are forecast to shift east into the central and
southern Appalachians later in the day, where orographic effects
may help bolster totals across parts of the region and raise flash
flooding concerns, especially in the more sensitive parts of the
central Appalachians.

Pereira


Day 4 and Day 5
Valid 12Z Thu Nov 05 2026 - 12Z Sat Nov 07 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent on both Thursday and Friday.

While there will be widespread rainfall across the Northeast for
the first time in 2.5 weeks in most areas, the combination of those
dry soils and poor instability limiting rainfall rates should both
work to prevent any flash flooding. The area will continue to be
watched should a future Marginal Risk be needed.

Wegman


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