000
WTNT42 KNHC 080853
TCDAT2

Tropical Storm Beryl Discussion Number  12
NWS National Hurricane Center Miami FL       AL022018
500 AM AST Sun Jul 08 2018

A burst of deep convection developed over the eastern portion of
Beryl's circulation just after the release of the previous
advisory.  The convective burst has expanded overnight and
the earlier exposed center of the cyclone is now located near
the northwestern edge of the convective cluster.  Subjective Dvorak
intensity estimates from TAFB and SAB are unchanged, and the initial
intensity remains 40 kt for this advisory.  An Air Force Reserve
reconnaissance aircraft is currently en route to Beryl and should
provide a better assessment of the cyclone's intensity this morning.

The intensity forecast reasoning is unchanged from the previous
advisory. Westerly vertical wind shear is expected to increase over
Beryl during the next 24 to 36 h, and the cyclone will be moving
into a drier mid-level environment.  As a result, Beryl is expected
to weaken and degenerate into a trough of low pressure over the
eastern Caribbean Sea.  However, the system will likely produce
strong gusty winds and locally heavy rainfall across the Leeward
Islands, the Virgin Islands, and Puerto Rico during the next few
days.

The tropical storm is moving quickly west-northwestward or 290/17
kt. Beryl should continue on this general heading with some
increase in forward speed as it is steered by a strong mid-level
ridge to the north.  The track guidance remains in fairly good
agreement but there has been some increase in the cross track
spread at 24 and 36 h with the GFS and HWRF along the southern
edge of the guidance and the ECMWF bracketing the northern side of
the envelope.  The NHC track is in the middle of the envelope,
close to the various consensus models, and in best agreement with
the HFIP corrected consensus.


Key Messages:

1. Tropical storm warnings and watches are in effect for portions
of the Lesser Antilles where Beryl is forecast to bring impacts
from wind and rainfall to some of the islands beginning late today
or tonight.

2. Although Beryl is forecast to degenerate into a trough of low
pressure over the eastern Caribbean, the system is likely to produce
strong gusty winds and locally heavy rainfall across the remainder
of the Leeward Islands, the Virgin Islands, Puerto Rico, and
Hispaniola through Tuesday.


FORECAST POSITIONS AND MAX WINDS

INIT  08/0900Z 13.7N  56.0W   40 KT  45 MPH
 12H  08/1800Z 14.7N  58.8W   40 KT  45 MPH
 24H  09/0600Z 15.9N  62.7W   35 KT  40 MPH
 36H  09/1800Z 17.4N  66.8W   30 KT  35 MPH
 48H  10/0600Z...DISSIPATED

$$
Forecaster Brown