ZCZC MIATCDAT4 ALL
TTAA00 KNHC DDHHMM

Post-Tropical Cyclone Humberto Discussion Number  30
NWS National Hurricane Center Miami FL       AL092019
1100 PM AST Thu Sep 19 2019

Satellite images show what little deep convection remains has been
displaced well to the north of the center of the cyclone, and it
can no longer be classified via the Dvorak technique.  Moreover,
cold air stratocumulus clouds over the western and southern
portions of the circulation are indicative of cold air advection
that is characteristic of an extratropical cyclone.  Therefore,
Humberto is now post-tropical and this will be the last advisory
issued by the National Hurricane Center on this system.

It is estimated that the cyclone still has hurricane-force winds
and based on continuity from previous estimates with a gradual
weakening rate, the current intensity is set at 85 kt.  Continued
gradual weakening is likely, and after 48 hours the system is
expected to merge with another extratropical low over the north
Atlantic.

The cyclone has turned north-northeastward along the eastern side
of a deep layer cyclonic circulation, with a current motion
estimate of 030/17 kt.  A turn toward the east-northeast is
expected in a day or so as the system moves within the mid-latitude
westerlies until dissipation.


Key Messages:

1. Large swells will continue to affect Bermuda, the northwestern
Bahamas, and the east coast of the United States from east-central
Florida to the Mid-Atlantic States during the next couple of days.
These swells could create life-threatening surf and rip current
conditions.


FORECAST POSITIONS AND MAX WINDS

INIT  20/0300Z 40.0N  58.0W   85 KT 100 MPH...POST-TROP/EXTRATROP
 12H  20/1200Z 41.8N  56.8W   70 KT  80 MPH...POST-TROP/EXTRATROP
 24H  21/0000Z 44.0N  54.0W   60 KT  70 MPH...POST-TROP/EXTRATROP
 36H  21/1200Z 45.5N  48.0W   55 KT  65 MPH...POST-TROP/EXTRATROP
 48H  22/0000Z 46.5N  40.5W   50 KT  60 MPH...POST-TROP/EXTRATROP
 72H  23/0000Z...DISSIPATED

$$
Forecaster Pasch

NNNN