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AGUS74 KWCO 171304
HMDNWC

National Hydrologic Discussion - EXPERIMENTAL
NWS National Water Center - Tuscaloosa AL
700 AM CST MON NOV 17 2025

UPDATE

A Limited impacts area was introduced across American Samoa today due to a
flash flooding threat. Otherwise, no significant changes to the FHO this
morning.

//RMF

Previous Discussion as follows:

...Flash and urban flooding possible for California through tomorrow...
...Flood threat developing over the Southern Plains into the Ozarks...

.California...
Isolated heavy rainfall will be possible through this evening, which will
bring a chance of isolated flooding to the region. The greatest threat of
impact will be in and around recently burned areas, where flash flooding
and debris flow may occur if heavy rainfall moves over. Additional rainfall
is  possible tomorrow. Flood impacts will be limited to urban areas and
recently burned areas along and west of the Transverse Range. The limited"
area on the FHO has been trimmed to the above described area.

.Southern Plains into the Ozarks...
Models have slightly slowed down the progression of the system going into
the middle of this week for the Ozarks, resulting in the threat shifting
more into Oklahoma late this week. Placement and timing of the rainfall has
varied significantly over the same period, but the last few runs of
multiple models have been consistent, increasing confidence that an
impactful hydrologic response may be possible in the region.

Given antecedent conditions, the rainfall should generally be beneficial.
However, many trees have most likely shed their leaves,the loss of canopy
interception will allow for the potential of increased direct runoff.
Hydrologic guidance, such as the NWM and the EC-forced GLOFAS signal that
the QPF totals may be enough to overwhelm the infiltration rates and allow
for runoff. Though forecast flows are generally around or above the 20%
AEP, suggesting that flooding impacts should not be significant over the
region. The limited" area on the FHO has been expanded to the west and
southwest to catch the area of expected rainfall.

//GKendrick

Additional National Water Center products are available at
www.weather.gov/owp/operations




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