231
WTNT45 KNHC 182045
TCDAT5

Hurricane Erin Discussion Number  30
NWS National Hurricane Center Miami FL       AL052025
500 PM EDT Mon Aug 18 2025

Erin`s cloud pattern has become somewhat less organized than
earlier today, likely as a result of some dry air intrusion over
the northwestern portion of the circulation and increased northerly
shear.  An AMSR microwave image from the GCOM satellite showed the
dry air intrusion which is consistent with the presence of arc
clouds emanating northwestward from the system.  The northerly
shear has also begun to restrict the outflow to the north of Erin.
The intensity is held at 120 kt for now, pending observations from
another Air Force Hurricane Hunter aircraft in a few hours.  This
intensity estimate is also consistent with a blend of objective
values from UW-CIMSS.

After a west-northwestward wobble earlier today, the hurricane has
resumed its northwest course with a motion estimate of 310/9 kt.
The track forecast reasoning remains basically unchanged.  Over
the next 72 hours or so, Erin should turn northward and move
through a weakness in the subtropical ridge, and on the western
side of a mid-level anticyclone.  Later in the forecast period, an
approaching mid-level trough should cause Erin to accelerate
northeastward over the northern Atlantic.

The model guidance and low-level water vapor imagery suggests that
the dry air incursion into Erin is probably temporary.  However,
given the degraded cloud pattern and the less conducive shear over
the system, not much additional strengthening is likely.  In any
event since the system will remain over warm waters for at least
the next 72 hours, Erin will likely retain major hurricane status
through the middle of the week.  The official intensity forecast is
at the high end of the model guidance.

Erin`s continued expanding wind field will result in rough ocean
conditions over much of the western Atlantic. It should be noted
that the 34- and 50-kt wind speed probabilities beyond 36 hours in
the text and graphical products are likely underestimating the risk
of those winds occurring.  This is because the forecast wind field
of Erin is considerably larger than average compared to the wind
field used to derive the wind speed probability product.

KEY MESSAGES:

1. Bands of heavy rainfall are expected over portions of Hispaniola
this evening, and through Tuesday for the Turks and Caicos, the
southeast Bahamas, and the easternmost central Bahamas.  Flash and
urban flooding are possible.

2. Tropical storm conditions are expected in the Turks and Caicos
Islands and in the southeast Bahamas through this evening.  Tropical
storm conditions are possible in portions of the central Bahamas
tonight through Tuesday.

3. Erin is expected 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 several days.
Beachgoers in those areas should follow advice from lifeguards,
local authorities, and beach warning flags.

4. Tropical storm conditions and coastal flooding are possible in
the North Carolina Outer Banks beginning late Wednesday where
Tropical Storm and Storm Surge Watches are in effect.  Interests in
Bermuda should also monitor the progress of Erin as strong winds are
possible beginning on Thursday.


FORECAST POSITIONS AND MAX WINDS

INIT  18/2100Z 24.0N  71.3W  120 KT 140 MPH
 12H  19/0600Z 24.9N  71.9W  120 KT 140 MPH
 24H  19/1800Z 26.5N  72.8W  115 KT 130 MPH
 36H  20/0600Z 28.4N  73.5W  105 KT 120 MPH
 48H  20/1800Z 30.5N  73.7W  100 KT 115 MPH
 60H  21/0600Z 32.7N  73.0W  100 KT 115 MPH
 72H  21/1800Z 34.8N  71.2W   95 KT 110 MPH
 96H  22/1800Z 38.0N  64.0W   85 KT 100 MPH
120H  23/1800Z 41.0N  56.5W   75 KT  85 MPH

$$
Forecaster Pasch