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Area forecast discussion 
National Weather Service San Juan PR
250 PM AST Friday Aug 1 2014

Synopsis... at 2 PM AST...Tropical Storm Bertha was located near 14.5n
and 60.3w or near 480 miles east southeast of Ponce PR. Tropical
Storm Warning in effect of Puerto Rico and the U.S. Virgin


Discussion...showers with thunderstorms developed this afternoon
over the northwest section of Puerto Rico. Strong thunderstorms
with frequent lighting was observed over San Sebastian...where
thunderstorms wind damage were reported. This activity is expected
to dissipated near sunset. Only light passing showers are executed
to prevail tonight over the U.S. Virgin Islands and eastern Puerto

Main weather feature which will affect the local area next 24 to
36 hours is Tropical Storm Bertha. Tropical Storm Bertha was
located near 480 miles east southeast of Ponce this afternoon.
Bertha will continue to move west northwest and will approach the
U.S Virgin Islands and Puerto Rico on Saturday. Weather is
expected to deteriorate rapidly starting Saturday morning and
continuing through Saturday night. Remember...a Tropical Storm
Warning is in effect for all of Puerto Rico and the U.S Virgin
Islands. Tropical Storm Warning means that tropical storm conditions are
expected somewhere within the warning this case within
the next 24 hours. preparations to protect life and
property should be completed before conditions deteriorate. The
onset of gusty winds and heavy rains can cause outside activities
to become dangerous. Refer to latest hurricane local statement for
further information.


Aviation...brief MVFR ceilings due scattered rain showers/thunderstorms and rain will continue at
least until 21z mainly over tjbq. VFR conds will prevail at all
other taf sites for the rest of today. However...the proximity of tc
Bertha will start to impact tncm and tkpk tonight and the rest of
the terminal early Saturday morning. Therefore...MVFR conds with
periods of brief IFR are expected through the end of the forecast
period. East-NE winds at 15 to 25 kts below fl100 becoming east-southeast and higher
after 02/12z.


Marine...seas below 6 feet tonight increasing 6-10 feet through Saturday
with higher seas to the right of the center of the track of tc
Bertha. Sustained winds 40-45 knots with gusts up to 60 knots. Winds and
seas begin to improve rapidly late Sat night.


Fire weather...a red flag warning continues in effect for Saint
Croix. This warning will expire at 5 PM AST this afternoon.


Preliminary point temps/pops...
sju 81 82 78 87 / 100 100 90 20
stt 79 81 80 82 / 100 100 90 10


Sju watches/warnings/advisories...
PR...Tropical Storm Warning for central interior-Culebra-eastern
interior-Mayaguez and vicinity-north Central-Northeast-
northwest-Ponce and vicinity-San Juan and vicinity-
southeast-southwest-Vieques-western interior.

Vi...Tropical Storm Warning for St Croix-St. Thomas/St. John/adjacent

Red flag warning until 5 PM AST this afternoon for St Croix.

Coastal waters...



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