276
WTNT45 KNHC 221436
TCDAT5

Subtropical Storm Josephine Discussion Number 4
NWS National Hurricane Center Miami FL AL102026
1100 AM AST Thu Oct 22 2026

Satellite imagery this morning indicates that an area of convection
has developed to the north of the center of Josephine, although the
convective curvature is less than it was last night. Just- received scatterometer data suggests the convective cluster is near or just
west of a developing frontal boundary. Satellite intensity estimates
have changed little since the previous advisory, and the
scatterometer shows winds near 50 kt west of the center. The initial
intensity remains 55 kt based on a subtropical cyclone intensity
estimate from TAFB and the possibility of the scatterometer
undersampling the maximum wind.

The initial motion is northeastward or 040/10 kt. GOES RGB airmass
imagery shows a mid- to upper-level trough extending from eastern
Canada southwestward into the northeastern US, and Josephine should
accelerate northeastward during the next 12-24 h as this trough
amplifies and approaches the cyclone. After 24 h or so, Josephine
should turn more eastward as it becomes embedded in the mid-
latitude westerlies. On the forecast track, the center of Josephine
will move away from the New England states today and pass south of
Nova Scotia and Newfoundland tonight and Saturday. The guidance is
again tightly clustered, and the new forecast track is similar to
the previous forecast.

The interaction between Josephine and the aforementioned trough
should cause the cyclone to develop fronts and become extratropical
during the next 12 h, and the scatterometer data suggests this
process is already underway. However, intensification is expected
during this transition and Josephine will become a hurricane-force extratropical low later tonight and on Friday. The dynamical models
are in good agreement that the cyclone should steadily weaken after
24 h, and they forecast Josephine to dissipate between 72 and 96 h
as it is absorbed by a new low pressure area developing to its
northeast. The new intensity forecast is based mainly on the global
physical models and it has only minor adjustments from the last
forecast. The wind radii forecasts have also been revised based on
the global model forecasts.

Since the coastal wind hazards associated with this system have been
covered for the last several days through non-tropical products
issued by local National Weather Service offices, those products
will remain in effect until the threat diminishes and Josephine
moves farther away from the U.S. coast over the next day or so.


FORECAST POSITIONS AND MAX WINDS

INIT 22/1500Z 39.2N 67.3W 55 KT 65 MPH
12H 23/0000Z 40.5N 64.6W 65 KT 75 MPH...POST-TROP/EXTRATROP
24H 23/1200Z 42.3N 60.2W 65 KT 75 MPH...POST-TROP/EXTRATROP
36H 24/0000Z 43.4N 56.9W 60 KT 70 MPH...POST-TROP/EXTRATROP
48H 24/1200Z 43.7N 54.3W 55 KT 65 MPH...POST-TROP/EXTRATROP
60H 25/0000Z 43.9N 50.4W 50 KT 60 MPH...POST-TROP/EXTRATROP
72H 25/1200Z 43.6N 45.2W 45 KT 50 MPH...POST-TROP/EXTRATROP
96H 26/1200Z...DISSIPATED

$$
Forecaster Beven
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--- scorpsmtpd
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