FOUS30 KWBC 070054
QPFERD

Excessive Rainfall Discussion
NWS Weather Prediction Center College Park MD
854 PM EDT Mon Apr 6 2026

Day 1
Valid 01Z Tue Apr 07 2026 - 12Z Tue Apr 07 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
FLORIDA...

...0100 UTC Update...
Have adjusted the MGNL Risk area across potions of Central and
South FL based on the latest observational and short-term CAM
guidance trends. This included trimming the northern extent, i.e.
areas north of Orlando, which are now north of the front
(significantly more stable environment with much lower short-term
rainfall rates). Otherwise, we did expand the western periphery of
the MGNL Risk area to the Gulf Coast in the Fort Myers-Naples I-75
corridor. This again given the trends, including available deep-
layer instability south of the front per the latest SPC
mesoanalysis, along with the low-mid layer shear profile favoring
slow-moving clusters with some back-building and thus training
potential south of the front. This area also meshes with the latest
ML output, including the CSU UFVS ERO first-guess, along with the
more elevated probabilities for isolated 2 to 3+ in/hr rainfall
rates per the latest HREF and RRFS.

Hurley


Day 2
Valid 12Z Tue Apr 07 2026 - 12Z Wed Apr 08 2026

...THERE IS A MARGINAL RISK OF EXCESSIVE RAINFALL OVER PORTIONS OF
THE EAST COAST OF THE FLORIDA PENINSULA...

21Z... Overall the environment described below is largely expected
to be the same. A small westward nudge of the boundary toward
central Broward and Miami-Dade Counties was made to reflect the
latest QPF trends.

Campbell

A cold front will be passing over Florida which allows for deep
moisture to pool across the southern two-thirds of the peninsula with
precipitable water values reaching into the 1.5 to 1.8 inch range
and moisture flux convergence along the front acts to focus and
support convection. The concern about excessive rainfall arises
from the locally heavy rainfall rates from any convection that
develops within such an environment as well as the fact that the
front should be slowing its southward motion keeps the window of
opportunity open longer for enhanced rainfall totals.

Bann

Day 3
Valid 12Z Wed Apr 08 2026 - 12Z Thu Apr 09 2026

...THERE CONTINUES TO BE A MARGINAL RISK OF EXCESSIVE RAINFALL OVER
PARTS OF THE FLORIDA PENINSULA...

21Z...Convection will stay mainly along the eastern coastline
maintaining an elevated threat for urban flash flooding concerns. A
small westward nudge of the boundary toward western Broward and
Miami- Dade/northward trim to central Miami- Dade Counties was made
for this period to reflect the latest QPF placement.

Campbell

A front draped across the southern portion of the Florida
peninsula acting as a focus for thunderstorms capable of producing
locally heavy rainfall across parts of the Florida peninsula. Some
of the guidance has a mesoscale low over the eastern Gulf that
begins to move towards the peninsula and starts to lift the front
northward during the latter part of the period. The inference is
that low level flow will be strengthening...especially on the
eastern side of the peninsula...which may enhance rainfall
amounts compared with amounts on Tuesday. Given the lack of
agreement within the suite of numerical guidance on where...or
if...this occurs preludes more than a Marginal risk area.

Bann


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