FOUS30 KWBC 130825
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
325 AM EST Fri Feb 13 2026

Day 1
Valid 12Z Fri Feb 13 2026 - 12Z Sat Feb 14 2026

...There is a marginal risk of excessive rainfall across portions 
of the Southern Plains today...

A deep upper-level trough will advance eastward across the
Southwest today. Diffluence and vorticity will spread over the 
Southern Plains tonight, where showers and thunderstorms are 
expected to proliferate along surface boundaries stemming from an 
area of surface low pressure. Instability will be modest 500-700 
J/Kg, but moisture will be quite anomalous, (PWATs 4-5 stndv & 99th
percentile) due to the arrival of subtropical Pacific moisture. A 
mitigating factor will be that antecedent conditions are mostly dry
(moderate to severe drought + low RSM) especially on the western 
end of the risk area.

Kebede


Day 2
Valid 12Z Sat Feb 14 2026 - 12Z Sun Feb 15 2026

...There is a slight risk of excessive rainfall from the ArkLaTex
to Mid-South on Saturday..

A mid-latitude cyclone develops and deepens beneath a PVA over the
Southern/Central Plains Friday night into Saturday. This system 
will combine two separate moisture regimes: one from the 
subtropical Pacific and one from the Gulf of Mexico to produce
scattered thunderstorms and heavy rainfall over parts of the 
Southern Plains, Lower/Middle Mississippi Valley and Tennessee/Ohio Valleys.

The slight and marginal risk areas were expanded from what was
depicted on our previous issuance. This was based on a broader qpf
footprint signal in the latest guidance. Some showers and 
thunderstorms from today's excessive rainfall threat will shift 
into Missouri and the Midwest today, while the main threat develops
within the warm sector to the south. 

A line of convection is expected to develop over the ArkLaTex this
evening and propagate eastward through the Lower Mississippi 
Valley, where favorable jet dynamics (strong LLJ 30-40kts and 
strong upper level divergence) could produce efficient rain rates. 
PWATs will also be 2-3 stndv above normal (90th percentile) from 
eastern Texas to northeastern Arkansas, where the current slight 
risk is in place. It's worth noting that the Euro has a slightly 
more southerly focused QPF footprint than the GFS and our current 
slight risk area depict.

Kebede


Day 3
Valid 12Z Sun Feb 15 2026 - 12Z Mon Feb 16 2026

...There is a marginal risk of excessive rainfall across portions
of the Mid-Atlantic and Southeast on Sunday...

The inherited marginal risk area over parts of the Mid-Atlantic
(central Virginia) down to the Gulf Coast of Mississippi, Alabama 
and the Florida Panhandle, was mostly unchanged. Contours were 
expanded north into central Virginia due in part to an increased 
signal in the GFS, but also due to clustering between several Euro,
Canadian and GEFS ensemble members.

Another marginal area was considered for parts of the northern and
central California coast, but was ultimately nixed in coordination
with local offices due to a lack of favorable moisture, forcing and
instability. All of which become more pronounced over Southern
California on by day 4.

Kebede
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