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fxca62 tjsj 201609 
afdsju

Area forecast discussion
National Weather Service San Juan PR
1209 PM AST Wed Sep 20 2017

Update...major Hurricane Maria producing widespread and dangerous
flash flooding across Puerto Rico. Major flooding occurring along
the Rio Grande de Loiza, Rio Grande de Manati and La Plata basins.
Dangerous winds will continue through this evening across Mainland
PR. The center of Maria should be exiting the north coast of
Puerto Rico shortly and the strongest hurricane storm force winds
should spread along the north central and northwest portions of
Puerto Rico through late this afternoon. Although, tropical storm
force winds could diminish this evening across the USVI and
portions of southeastern PR...outer bands of Maria with strong
thunderstorms will move across these areas. Currently, scattered
thunderstorms with frequent lighting are being observed along the
eastern coastal waters of the USVI.



&&



Aviation...sustained hurricane and tropical storm force winds
will continue for the next several hours across the PR and USVI
terminals...IFR/LIFR condtions expected to prevail for much of the
forecast period. Check with authorities for Airport closures.



&&

Marine...tropical storm force winds will likely continue across
the Caribbean waters through this afternoon and hurricane force
winds across the Atlantic waters through late tonight. There is no
chance of a successful passage through this storm.



&&

Previous discussion... /issued 721 am AST Wed Sep 20 2017/

Synopsis...core of extremely dangerous Hurricane Maria moving
over Puerto Rico.

Discussion...hurricane force winds will likely continue across
the USVI, Vieques and Culebra through the afternoon hours; and
across Puerto Rico through tonight. These winds will bring
catastrophic damage. Severe injury is possible in less than a
strong structure. Now is the time to remain safely sheltered from
the storm.

Rainfall associated with Hurricane Maria will continue to lead to
rapid rises along all streams and rivers at the U.S. Virgin
Islands and Puerto Rico. Mudslides are also expected. Any homes in
low- lying areas near rivers and streams will be flooded and
flooding may leave residents with no Avenue of escape. Those in
coastal areas may have streams and rivers backed up from storm
surge created by the hurricane.

Aviation...sustained hurricane force winds will continue during
the next few hours with IFR/LIFR condtions. Check with
authorities for Airport closures.

Marine...hurricane force winds will likely continue across the
Anegada Passage and the Caribbean waters through this afternoon,
and across the Atlantic coastal waters through tonight. There is
no chance of a successful passage through this storm.

&&

Preliminary point temps/pops...
sju 82 76 83 76 / 100 100 80 20
stt 82 76 82 76 / 100 90 80 60

&&

Sju watches/warnings/advisories...
PR...Hurricane 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.

Flash Flood Watch through Friday afternoon 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...Hurricane Warning for St Croix-St... John...and
adjacent islands.

Flash Flood Watch through Friday afternoon for St Croix-
St... John...and adjacent islands.

Am...Hurricane Warning for Anegada Passage southward to 17n-Atlantic
waters of Puerto Rico and USVI from 10 nm to 19.5n-
Caribbean waters of Puerto Rico from 10 nm to 17n-coastal
waters of northwestern Puerto Rico out 10 nm-coastal waters
of southwestern Puerto Rico out 10 nm-coastal waters of
northern Puerto Rico out 10 nm-coastal waters of northern
USVI and Culebra out 10 nm-coastal waters of southern
Puerto Rico out 10 nm-coastal waters of southern USVI
Vieques and eastern Puerto Rico out 10 nm-Mona Passage
southward to 17n.

Flash Flood Watch through Friday afternoon for coastal waters of
southwestern Puerto Rico out 10 nm-coastal waters of
northern USVI and Culebra out 10 nm-coastal waters of
southern Puerto Rico out 10 nm-coastal waters of southern
USVI Vieques and eastern Puerto Rico out 10 nm.

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