370
AGUS74 KWCO 131540
HMDNWC

National Hydrologic Discussion - EXPERIMENTAL
NWS National Water Center - Tuscaloosa AL
1015 AM CDT WED AUG 13 2025

.Synopsis...
Isolated flood potential across the Southern Appalachians, Southeast, into
the Gulf Coast... Major flooding ongoing from a glacial dam release and
small stream flooding possible in Alaska...

.Southern Appalachians, Southeast, into the Gulf Coast...
Isolated flash, urban, and small stream flooding is possible across parts
of the Southeast and Gulf Coast through today in response to heavy
convective rainfall. The primary areas of concern are along the Southern
Appalachian Mountains into the Tennessee Valley and along the Florida
Panhandle. Not only have models been fairly consistent in placing heavier
QPF totals over these areas, but also the antecedent conditions are more
favorable for the formation of runoff conditions. The Southern Appalachians
are particularly primed, with topsoils close to saturation (65 - 80% RSM, 0
- 10 cm, NASA SPoRT) and streamflows running near normal to much above
normal. Given these conditions and the complex terrain of the region,
flooding impacts are possible anywhere heavy rainfall sets up. Outside of
the Southern Appalachians, the flood threat is expected to be mostly
flash/urban in nature given less favorable antecedent conditions.

.Alaska...
Mendenhall Glaciers Suicide Basin glacier dammed lake near Juneau, AK has
begun to release and is forecast to exceed the peak of record from last
years release. The Mendenhall River is currently above the major flood
threshold and rising, with the peak expected sometime this morning (local
time). Rapid small stream rises and nuisance flooding are possible in
northwest AK through today due to moderate to heavy rainfall.

//Bliss

$$