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912
AGUS74 KWCO 021508
HMDNWC

National Hydrologic Discussion - EXPERIMENTAL
NWS National Water Center - Tuscaloosa AL
1007 AM CDT WED JUL 2 2025

.Synopsis...
Periods of heavy rain are expected across Florida through the weekend,
causing isolated flash and urban flooding, and potentially river flooding
in west-central FL... Isolated flash and urban flooding today across the
Mid-Atlantic... Isolated flooding potential across the Southwest into the
Southern Plains through Thursday... Renewed flood potential increasing for
the Northern Plains...

.Florida...
Periods of heavy rainfall will likely produce isolated flash and urban
flooding impacts along the I-10 and I-75 corridors in FL through at least
day 3 (Fri) and potentially into the weekend. Flooding impacts should be
mostly constrained to urban areas, with exception to west-central FL from
the Tampa area to Cape Coral (Tampa Bay and Peace River Basins). Fairly
widespread 5 - 10" rainfall totals by the end of the week may be enough to
elicit isolated minor river flooding, particularly on the Little Manatee,
Manatee and Myakka Rivers. Both the GFS and NBM-forced NWM are indicating
isolated river responses across the Sarasota to Tampa area now, with
probabilities for High Water Flows (1.3 ARI) increasing into the 25 - 50%
range. NBM and GFS QPF totals are comparable to WPC, increasing confidence
in potential responses across the region, but even with these higher totals
over 7", magnitude of response from the NWM is still muted overall with
rivers struggling to exceed the 50% AEP flow.

.Mid-Atlantic...
Isolated flash and urban flooding is possible day 1 (Wed) as periods of
heavy rainfall are expected with the cold front pushing through the region.
The greatest area of concern is south-central VA into eastern NC. Soil
conditions are wet across south-central VA (NASA SPoRT 0 - 10 cm RSM),
however the heaviest rainfall totals (1 - 3"+) are expected across eastern
NC where soils remain quite dry (NASA SPoRT 0 - 10 cm RSM). This offset of
heaviest rainfall totals and more vulnerable antecedent conditions should
help mitigate widespread hydrologic responses across the region. The
HRRR-forced NWM short range forecast indicates very isolated potential for
rapid onset flooding, which is the expected response as most of any
flooding impacts should remain in urban areas.

.Southwest into the Southern Plains...
Remnant tropical moisture and areas of convection will continue to produce
multiple rounds of heavy rainfall, and potentially isolated flooding,
through day 2 (Thu) across AZ, NM, and west TX. Heavy rainfall rates in the
terrain across the region will introduce the typical flash and arroyo
flooding threat, as well as potential flooding impacts across recently
burned areas. In western TX in the Odessa to San Angelo area, the NWM is
showing isolated potential for rapid onset flooding in this region that has
elevated soil moisture (70 - 90% 0 - 10cm RSM, NASA SPoRT) suggesting a
locally increased threat of flash flooding through this evening.

.Northern Plains...
Rainfall returns to the region on days 3 - 4 (Fri - Sat), potentially
introducing a new and renewed flood threat to eastern NE, IA, and southern
MN by this weekend. Rainfall amounts are generally pretty low (1.5"
totals) however much of the region has been wet recently, with streamflows
still above normal across the aforementioned regions and multiple rivers
still in flood across southern MN from last weeks rainfall. The NBM and
GFS-forced NWM are showing potential for river rises across southern MN
through eastern NE by the end of this week, however much of the signal is
coming from a system in the middle of next week, with which there is very
low confidence.

//JEC

$$