Hurricane Watch is now in effect for the USVI

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Anthony
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Hurricane Watch is now in effect for the USVI

Post by Anthony »

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE SAN JUAN PR
918 PM AST MON SEP 4 2017

...HURRICANE WATCH IS IN EFFECT...

AMZ710-712-715-722-725-732-735-741-742-745-050930-
/O.CON.TJSJ.HU.A.1011.000000T0000Z-000000T0000Z/
ATLANTIC WATERS OF PUERTO RICO AND USVI FROM 10 NM TO 19.5N-
COASTAL WATERS OF NORTHERN PUERTO RICO OUT 10 NM-
COASTAL WATERS OF NORTHERN USVI AND CULEBRA OUT 10 NM-
ANEGADA PASSAGE SOUTHWARD TO 17N-
COASTAL WATERS OF SOUTHERN USVI VIEQUES AND EASTERN PUERTO RICO
OUT 10 NM-CARIBBEAN WATERS OF PUERTO RICO FROM 10 NM TO 17N-
COASTAL WATERS OF SOUTHERN PUERTO RICO OUT 10 NM-
MONA PASSAGE SOUTHWARD TO 17N-
COASTAL WATERS OF NORTHWESTERN PUERTO RICO OUT 10 NM-
COASTAL WATERS OF SOUTHWESTERN PUERTO RICO OUT 10 NM-
918 PM AST MON SEP 4 2017

...HURRICANE WATCH REMAINS IN EFFECT...

* WINDS...WINDS OF 74 MPH OR HIGHER POSSIBLE ACROSS THE OFFSHORE
ATLANTIC WATERS.

* WAVES/SEAS...20 FEET OR GREATER ACROSS THE NEARSHORE ATLANTIC
WATERS, WITH 30 TO 40 FEET ACROSS THE OFFSHORE ATLANTIC WATERS.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

A HURRICANE WATCH IS ISSUED WHEN SUSTAINED WINDS OF 64 KTS OR
74 MPH OR HIGHER ASSOCIATED WITH A HURRICANE ARE POSSIBLE WITHIN
48 HOURS.
Anthony for Virgin Islands On Line
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Anthony
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Re: Hurricane Watch is now in effect for the USVI

Post by Anthony »

The 11 p.m. NHC discussion:

Hurricane Irma Discussion Number 23
NWS National Hurricane Center Miami FL AL112017
1100 PM AST Mon Sep 04 2017

Irma's satellite presentation remains quite impressive with a
well-defined eye and a symmetrical CDO containing very cold cloud
tops. Flight-level and SFMR-observed surface winds from NOAA and
Air Force Hurricane Hunter aircraft indicate that the current
intensity is about 120 kt. Since the hurricane will be moving
through an environment of low vertical wind shear, a moist mid-level
atmosphere, and increasing upper-ocean heat content, additional
intensification is likely. The only expected impediment to
strengthening should be eyewall replacement cycles, which are
difficult to predict. The official intensity forecast is very
close to the latest model consensus, ICON. Although the consensus
of the guidance shows slight weakening in the 96- to 120-hour time
frame, Irma is forecast to remain a powerful hurricane throughout
the 5-day forecast period.

Center fixes from the aircraft indicate a westward motion of about
270/11 kt. Irma should turn toward the west-northwest tomorrow
while it is steered by the flow to the south of a mid-level ridge.
A broad trough is forecast to amplify over the eastern U.S. in
72 hours and then lift northeastward leaving a weakness in the ridge
to north of the hurricane. This should cause a slowing of the
forward speed near the end of the forecast period. The official
track forecast is similar to the previous one and is close to the
model consensus.

Users are reminded to not focus on the exact forecast track,
especially at the longer ranges, since the average NHC track errors
are about 175 and 225 statute miles at days 4 and 5, respectively.

KEY MESSAGES:

1. Irma is expected to affect the northeastern Leeward Islands a
dangerous major hurricane, accompanied by life-threatening wind,
storm surge, and rainfall impacts. Hurricane warnings are in effect
for portions of the Leeward Islands. Preparations should be rushed
to completion, as tropical-storm force winds are expected to first
arrive in the hurricane warning area by late Tuesday.

2. Irma is also expected affect the British and U.S. Virgin
Islands and Puerto Rico as a dangerous major hurricane later this
week. Hurricane warnings have been issued for these areas, and
tropical-storm-force winds could arrive in these areas by early
Wednesday.

3. Irma could directly affect Hispaniola, the Turks and Caicos, the
Bahamas, and Cuba as a dangerous major hurricane later this week.
Residents in these areas should monitor the progress of Irma and
listen to advice given by officials.

4. There is an increasing chance of seeing some impacts from Irma in
the Florida Peninsula and the Florida Keys later this week and this
weekend. Otherwise, it is still too early to determine what direct
impacts Irma might have on the continental United States. However,
everyone in hurricane-prone areas should ensure that they have their
hurricane plan in place.

FORECAST POSITIONS AND MAX WINDS

INIT 05/0300Z 16.7N 55.6W 120 KT 140 MPH
12H 05/1200Z 16.9N 57.4W 125 KT 145 MPH
24H 06/0000Z 17.5N 60.0W 130 KT 150 MPH
36H 06/1200Z 18.3N 62.7W 130 KT 150 MPH
48H 07/0000Z 19.3N 65.5W 125 KT 145 MPH
72H 08/0000Z 21.2N 71.0W 120 KT 140 MPH
96H 09/0000Z 22.5N 76.0W 115 KT 130 MPH
120H 10/0000Z 24.0N 80.0W 115 KT 130 MPH
Anthony for Virgin Islands On Line
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