849
WTNT45 KNHC 222032
TCDAT5

Post-Tropical Cyclone Erin Discussion Number  46
NWS National Hurricane Center Miami FL       AL052025
500 PM AST Fri Aug 22 2025

Erin has now become a powerful extratropical low.  While there is
still deep convection near the center, scatterometer data clearly
shows that Erin has become frontal.  Thus, extratropical transition
has been completed, and this is the last NHC advisory.  The initial
intensity remains 80 kt based on the multiple earlier scatterometer
winds near 70 kt, with very large gale- and storm-force wind-radii
noted.

While the general track and intensity forecast is about the same as
before, one specific marine hazard to highlight is the consistent
development of a strong sting jet in the southern semicircle of Erin
by Sunday, as well as a very large hurricane-force wind field.
Model guidance now suggest that a maximum of 80-90 kt is possible,
and the NHC intensity forecast is raised to 85 kt then.  No other
noteworthy changes were made to the previous forecast.

Additional information on this system can be found in High Seas
Forecasts issued by the National Weather Service, under AWIPS
header NFDHSFAT1, WMO header FZNT01 KWBC, and online at
ocean.weather.gov/shtml/NFDHSFAT1.php

KEY MESSAGES:

1. Erin will continue to produce life-threatening surf and rip
currents along the beaches of the Bahamas, much of the east coast of
the U.S., Bermuda, and Atlantic Canada during the next few days.
Beachgoers in those areas should follow advice from lifeguards,
local authorities, and beach warning flags.

2. Some coastal flooding is expected at times of high tide along
portions of the U.S. Mid-Atlantic and New England coasts through
tonight, making some roads impassable.  Large waves along the coast
could also cause significant beach erosion and overwash.

3. Gale-force wind gusts are possible along the coast of Nova Scotia
today and the Avalon Peninsula of Newfoundland on Saturday.


FORECAST POSITIONS AND MAX WINDS

INIT  22/2100Z 40.0N  59.7W   80 KT  90 MPH...POST-TROP/EXTRATROP
 12H  23/0600Z 41.5N  54.5W   80 KT  90 MPH...POST-TROP/EXTRATROP
 24H  23/1800Z 44.0N  45.5W   75 KT  85 MPH...POST-TROP/EXTRATROP
 36H  24/0600Z 48.0N  35.5W   75 KT  85 MPH...POST-TROP/EXTRATROP
 48H  24/1800Z 52.0N  27.0W   85 KT 100 MPH...POST-TROP/EXTRATROP
 60H  25/0600Z 55.0N  23.0W   65 KT  75 MPH...POST-TROP/EXTRATROP
 72H  25/1800Z 58.0N  21.0W   55 KT  65 MPH...POST-TROP/EXTRATROP
 96H  26/1800Z 59.0N  21.0W   45 KT  50 MPH...POST-TROP/EXTRATROP
120H  27/1800Z 57.0N  17.5W   40 KT  45 MPH...POST-TROP/EXTRATROP

$$
Forecaster Blake