000
WTNT43 KNHC 060846
TCDAT3

TROPICAL STORM BERTHA DISCUSSION NUMBER  22
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL032014
500 AM AST WED AUG 06 2014

Deep convection continues to pulse downshear of the center of
Bertha, as the tropical cyclone is situated in a favorable region
for forced ascent in the equatorward entrance region of an upper-
level jet streak. The initial intensity remains 45 kt based on the
Dvorak classification from TAFB and an earlier ASCAT pass that
showed some 40-45 kt winds east of the center. As Bertha becomes
embedded in the jet, the vertical shear will increase in the next 12
to 24 hours. This should result in the low-level circulation
decoupling from the convection while the cyclone becomes embedded in
a baroclinic zone. Bertha should be post-tropical by 24 hours, and
then gradually decay as an extratropical cyclone. Bertha is
expected to be absorbed by day 5, although this could occur sooner.

The latest satellite fixes indicate an initial motion of 055/24.
Bertha is well embedded in deep-layer southwesterly flow ahead of a
mid-latitude trough, and will continue moving northeastward over the
north Atlantic for the next day or so before turning eastward by 72
hours. The new NHC track is largely an update of the previous one,
and is close to guidance provided by the NOAA Ocean Prediction
Center.

FORECAST POSITIONS AND MAX WINDS

INIT  06/0900Z 39.0N  65.4W   45 KT  50 MPH
 12H  06/1800Z 40.8N  61.7W   45 KT  50 MPH
 24H  07/0600Z 43.6N  55.7W   40 KT  45 MPH...POST-TROP/EXTRATROP
 36H  07/1800Z 46.0N  49.9W   40 KT  45 MPH...POST-TROP/EXTRATROP
 48H  08/0600Z 48.0N  44.0W   40 KT  45 MPH...POST-TROP/EXTRATROP
 72H  09/0600Z 48.5N  28.0W   35 KT  40 MPH...POST-TROP/EXTRATROP
 96H  10/0600Z 48.5N  12.5W   35 KT  40 MPH...POST-TROP/EXTRATROP
120H  11/0600Z...ABSORBED

$$
Forecaster Brennan