FOUS30 KWBC 030830
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
330 AM EST Tue Mar 3 2026

Day 1
Valid 12Z Tue Mar 03 2026 - 12Z Wed Mar 04 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FOR PORTIONS OF
THE MIDWEST AND OHIO VALLEY...

Models have solidified their agreement in an axis of 1-2 inch
rainfall totals generally from northeastern Missouri eastward
through southern Ohio. These totals will coincide with an east-west
oriented front across the region, with point forecast soundings
suggesting fairly fast cellular motions and minimal surface-based
instability. The main contributor for flash flood potential with
this axis is repeating/training rainfall, though dry antecedent 
conditions remain a mitigating factor for a larger-scale flash 
flood risk. One exception to this is West Virginia - soil 
moistures are relatively wet there compared to points west. 
Rainfall totals may be somewhat lighter there too though (0.5-1.5 
inches), also keeping any flash flood potential isolated.

Cook


Day 2 Valid 12Z Wed Mar 04 2026 - 12Z Thu Mar 05 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL FROM NORTH TEXAS
NORTHEASTWARD INTO THE OHIO VALLEY...

Minimal changes are made to the inherited outlook. At the mid-
levels, an approaching trough will reach the central Plains during
the forecast period. As this occurs, strengthening, confluent low-
level flow from north Texas into the Missouri Ozarks will aid in
moisture transport and eventually deep convective development
especially during the afternoon/evening hours. That convective 
development will migrate from southwest to northeast within the
aforementioned warm conveyor, with areas of training/repeating
possible along with local rainfall totals exceeding 3 inches
through 12Z Thursday. The collocation of these rainfall totals with
varied/sensitive terrain over southwest Missouri/northwest Arkansas
suggests that higher probabilities and a Slight Risk may need to be
introduced at some point. Lingering concerns regarding antecedent
conditions (very dry soils) and eventual convective evolution
(models exhibiting a slight westward trend over the past 24 hours)
gives pause on introducing an upgrade at this time, however.
Current trends suggest that the greatest risk of flash flooding 
will exist along an axis from Fayetteville, AR to Rolla, MO, 
though this axis may change between now and Wednesday 
afternoon/evening.

Farther northeast, areas of rain (approaching 1-1.5 inch total in
spots) will develop from southern Illinois eastward through West
Virginia in similar locations that are expected to receive 1-2
inches of rain during the D1 forecast period (Tuesday into Tuesday
night). Soils should continue to moisten during this period, with
isolated instances of flash flooding remaining possible.

Cook


Day 3 Valid 12Z Thu Mar 05 2026 - 12Z Fri Mar 06 2026

The probability of rainfall exceeding flash flood guidance is less
than 5 percent.

Models are in general agreement that longwave trough will deepen
across the Intermountain West, spreading southwesterly flow aloft
over a large part of the Great Plains. Meanwhile, low-level
moisture advection will aid in an airmass characterized by 1.25-1.5
inch PW values along and just east of a dryline generally extending
from near Goodland to near Amarillo. Models depict scattered
convection developing amid supercellular wind fields Thursday
afternoon, with a mix of cells and linear segments possible along
parts of the dryline. Local cell mergers may result in a couple 
spots of 2-3 inch rainfall totals in this regime, though the 
overall footprint of heavier rainfall should be too small to even 
delineate a Marginal Risk area at this timeframe. Antecedent dry
conditions/drought are also mitigating factors for flash flood 
potential. This scenario will need to be monitored for any 
potential increase in convective coverage that might necessitate a 
Marginal in later outlooks.

Cook
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