BULLETIN
Tropical Storm Beryl Advisory Number 13
NWS National Hurricane Center Miami FL AL022018
1100 AM AST Sun Jul 08 2018
...BERYL MOVING QUICKLY WEST-NORTHWESTWARD TOWARD THE LESSER
ANTILLES WITH NO CHANGE IN STRENGTH...
SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION
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LOCATION...14.4N 57.9W
ABOUT 210 MI...335 KM E OF MARTINIQUE
ABOUT 235 MI...380 KM ESE OF DOMINICA
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 23 MPH...37 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES
WATCHES AND WARNINGS
--------------------
CHANGES WITH THIS ADVISORY:
The Government of Barbados has discontinued the Tropical Storm
Watch for Barbados.
SUMMARY OF WATCHES AND WARNINGS IN EFFECT:
A Tropical Storm Warning is in effect for...
* Dominica
* Guadeloupe
A Tropical Storm Watch is in effect for...
* Martinique, St. Martin, and St. Barthelemy
* Saba and St. Eustatius
* St. Maarten
A Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning area.
A Tropical Storm Watch means that tropical storm conditions are
possible within the watch area.
Interests elsewhere in the Leeward Islands, the Virgin Islands,
Puerto Rico, and the Dominican Republic should monitor the progress
of Beryl
DAT2
Tropical Storm Beryl Discussion Number 13
NWS National Hurricane Center Miami FL AL022018
1100 AM AST Sun Jul 08 2018
An Air Force Reserve reconnaissance aircraft investigating Beryl
earlier this morning was unable to find a closed low-level center.
However, the wind data from the aircraft indicated that a sharp
through did exist northeastward of the deep convection located in
the northeastern quadrant of the larger circulation. Since that
time, a stronger burst of convection has developed over the sharp
trough, and the assumption is that the convection could have
spun up a new center. For that reason, the system is still being
considered as a tropical cyclone for this advisory. The highest
850-mb flight-level wind measured was 56 kt in the northeast quad,
which equates to about a 45-kt surface wind. However, the advisory
intensity is being maintained at 40 kt in case the recent convective
development doesn't persist. Another reconnaissance mission into
Beryl is scheduled for this evening.
The initial motion estimate is 290/20 kt. Beryl is expected to
maintain this quick west-northwestward motion through dissipation
due to the strong and broad deep-layer ridge that extends
east-to-west across most of the subtropical Atlantic Ocean. The
latest model guidance remains tightly packed about the previous
advisory track, so no significant changes were required.
For now, Beryl seems to have found a sweet spot where the vertical
wind shear is a little lower and more difluent based on water vapor
imagery. However, this localized favorable upper-level wind flow
pattern is expected to be short-lived and give way to more hostile
shear conditions by 12 hours and beyond when the shear is forecast
to increase to more than 25 kt from the west. The result should be
a rapid degeneration of the cyclone into an open wave by 24 h when
the system will be moving 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 couple of days. On days 3-5, there appears to
be an opportunity for the remnants of Beryl to regenerate into a
tropical cyclone when the system moves through the Bahamas and into
the southwestern Atlantic. Vertical wind shear conditions are
forecast by most of the models to be light, with even the
possibility of the development of a weak upper-level anticyclone
across the Bahamas. The combination of the favorable upper-level
wind flow pattern in conjunction with sea-surface temperatures of
28-29 deg C should yield conditions conducive for the reformation of
a tropical cyclone, although Beryl's low-level remnants are likely
to be significantly disrupted by Hispaniola and could take some time
to reform.
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 08/1500Z 14.4N 57.9W 40 KT 45 MPH
12H 09/0000Z 15.4N 60.8W 40 KT 45 MPH
24H 09/1200Z 16.8N 64.9W 35 KT 40 MPH...TROPICAL WAVE
36H 10/0000Z 18.4N 68.8W 30 KT 35 MPH...TROPICAL WAVE
48H 10/1200Z...DISSIPATED
$$
Forecaster Stewart
