WTNT34 KWNH 111500
TCPAT4

BULLETIN
Post-Tropical Cyclone Isaias Advisory Number  20
NWS Weather Prediction Center College Park MD   AL092026
1100 AM EDT Sun Oct 11 2026

...FLASH FLOOD THREAT FROM ISAIAS IS DECREASING BUT SOME
RISK CONTINUES TODAY ACROSS PORTIONS OF THE APPALACHIANS AND
MID-ATLANTIC...


SUMMARY OF 1100 AM EDT...1500 UTC...INFORMATION
-----------------------------------------------
LOCATION...37.5N 84.0W
ABOUT 180 MI...285 KM NE OF NASHVILLE TENNESSEE
MAXIMUM SUSTAINED WINDS...25 MPH...35 KM/H
PRESENT MOVEMENT...ENE OR 65 DEGREES AT 22 MPH...35 KM/H
MINIMUM CENTRAL PRESSURE...1010 MB...29.83 INCHES


WATCHES AND WARNINGS
--------------------
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:

Flood Watches are in effect for...
* Portions of the Central and Southern Appalachians

Wind Advisory is in effect for...
* Portions of the Central Appalachians


DISCUSSION AND OUTLOOK
----------------------
At 1100 AM EDT (1500 UTC), the center of Post-Tropical Cyclone
Isaias was located near latitude 37.5 North, longitude 84.0 West.
The post-tropical cyclone is moving toward the east-northeast near
22 mph (35 km/h) and this motion is expected to continue today
before the low dissipates over West Virginia this evening.

Maximum sustained winds are near 25 mph (35 km/h) with higher gusts.
Little change in strength is forecast during the next 12 hours,
with the low dissipating thereafter.

The estimated minimum central pressure is 1010 mb (29.83 inches).


HAZARDS AFFECTING LAND
----------------------
Key messages for Isaias can be found in the Tropical Cyclone
Discussion under AWIPS header MIATCDAT4 and WMO header WTNT44 KNHC.

RAINFALL: Additional rainfall of 1 to 3 inches is possible today
across portions of the Central Appalachians into the Mid-Atlantic,
with localized flash and urban flooding possible. In western North
Carolina, rainfall is diminishing, but rapid river rises and
flooding remain possible today.

For a complete depiction of forecast rainfall associated with
Isaias, please see the National Weather Service Storm Total Rainfall
Graphic available at
hurricanes.gov/graphics_at4.shtml?rainqpf and the Flash Flood Risk
graphic at hurricanes.gov/graphics_at4.shtml?ero.

For a list of rainfall observations (and wind reports) associated
with Isaias,  see the companion storm summary at WBCSCCNS4 with the
WMO header ACUS44 KWBC or at the following link:
www.wpc.ncep.noaa.gov/discussions/nfdscc4.html.

TORNADOES: A couple of tornadoes are possible today across the
Piedmont and Coastal Plain of Virginia and North Carolina.

SURF: Swells from Isaias will continue to affect much of the
Gulf and Southeast coasts of the United States today. These swells
are likely to cause life-threatening surf and rip current
conditions. Please consult products from your local weather office.

A depiction of rip current risk for the United States can be found
at: hurricanes.gov/graphics_at4.shtml?ripCurrents


NEXT ADVISORY
-------------
This is the last public advisory issued by the Weather Prediction
Center on this system.

$$
Forecaster Chenard