Hurricane Kirk Discussion Number  22
NWS National Hurricane Center Miami FL       AL122024
500 PM AST Fri Oct 04 2024

Kirk has changed little in structure during the past several hours 
and remains an impressive hurricane with a well-defined eye inside 
a central dense overcast.  There has been no recent microwave 
imagery to determine if the apparent outer eyewall seen earlier is 
still there.  The various subjective and objective satellite 
intensity estimates are mostly near 115 kt, so the initial 
intensity for this advisory is set at that.

The initial motion is now 325/10.  Kirk is currently approaching a 
large break in the subtropical ridge caused by a deep-layer low 
centered near 33N 61W.  During the next 48 h, the hurricane should 
recurve through this break and accelerate northeastward into the 
mid-latitude westerlies.   After that time, the cyclone should move 
quickly east-northeastward across the northern and northeastern 
Atlantic.  The track guidance more or less is the same as seen in 
the previous advisory, with the exception of a southward nudge near 
96 h.  The new forecast track also has this nudge, but is otherwise 
little changed from the previous track.

Fluctuations in intensity are likely during the next 12 h due to the
possible eyewall replacement cycle.  After that, Kirk should 
encounter increasing southwesterly shear and move over cooler sea 
surface temperatures, which should cause a steady weakening. 
Extratropical transition is likely to begin between 60-72 h and be 
complete by 96 h, with Kirk becoming a strong extratropical cyclone 
over the northeastern Atlantic.  The new intensity forecast again 
follows the general trends of the intensity guidance, and is closest 
to the GFS model forecast during the extratropical stage.

Even though Kirk is expected to recurve over the open Atlantic, its
strong intensity and increasing size will result in large ocean
swells that will propagate far away from the hurricane. These swells
will likely increase the risk of dangerous surf and rip currents
across the Leeward Islands beginning this evening, Bermuda and the
Greater Antilles by Saturday, much of the U.S. East Coast, Atlantic
Canada, and the Bahamas by Sunday, and the Azores by Monday. For
more information on this hazard, see products issued by your local
weather office.


FORECAST POSITIONS AND MAX WINDS

INIT  04/2100Z 23.7N  49.4W  115 KT 130 MPH
12H  05/0600Z 25.5N  50.0W  115 KT 130 MPH
24H  05/1800Z 28.5N  50.1W  110 KT 125 MPH
36H  06/0600Z 32.0N  49.1W  100 KT 115 MPH
48H  06/1800Z 35.6N  46.5W   90 KT 105 MPH
60H  07/0600Z 39.1N  42.0W   80 KT  90 MPH
72H  07/1800Z 42.0N  36.0W   70 KT  80 MPH
96H  08/1800Z 45.0N  19.0W   50 KT  60 MPH...POST-TROP/EXTRATROP
120H  09/1800Z 49.5N   3.0W   45 KT  50 MPH...POST-TROP/EXTRATROP

$$
Forecaster Beven