Sunday, October 02, 2011

Hurricane Ophelia and The Extratropical Cyclone Update Six






WOCN31 CWHX 022345
Tropical cyclone information statement updated by the Canadian
Hurricane Centre of Environment Canada at 8:55 PM ADT Sunday
2 October 2011.
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Tropical cyclone information statement for:
      Newfoundland
      Nova Scotia.

      For hurricane Ophelia.

      The next statement will be issued by 3:00 AM ADT.

      Hurricane Ophelia beginning to turn toward the northeast -
      Expected to track near the Avalon Peninsula Monday morning as a
      Strong post-tropical storm.

---------------------------------------------------------------------
==discussion==
1. Summary of basic information at 9:00 PM ADT.

Location: near 43.3 north 58.8 west.
About 120 kilometres southeast of Sable Island.
Maximum sustained winds: near 148 km/hour.
Present movement: north-northeast at 52 km/hour.
Minimum central pressure: 970 MB.

2. Public weather impacts and warnings summary.

A tropical storm watch is in effect for the Avalon Peninsula.
Rainfall warnings are in effect for Southeastern Newfoundland.

Ophelia has begun to weaken as it moves toward an environment that
will lead to further rapid weakening.  A frontal zone from Southern
Newfoundland to south of Yarmouth will drift northward tonight with
occasional downpours associated with it.  Rain from Ophelia will
reach Cape Breton tonight then affect Southeastern Newfoundland
Monday morning.

Computer models are still showing different scenarios for Ophelia's
track - ranging from Placentia Bay in Newfoundland to 100 kilometres
south of the Avalon.

A. Wind.

The greatest chance for strong winds from Ophelia is over
Southeastern Newfoundland.  There is about a 70% chance of tropical
storm force winds over the Avalon Peninsula, hence the tropical storm
watch has been maintained.  Tropical storm force winds are
approximately 60 gusting to 90 km/h.  Chance of hurricane-force gusts
(120 km/h) in this area remains low at 20% mainly because the maximum
winds should remain offshore.

B. Rainfall.

Rainfall warnings have been issued for Southeastern Newfoundland.

The afore-mentioned frontal system over the Maritimes could tap in to
some of Ophelia's moisture tonight and into Monday giving a good
possibility of heavy rainfall over Eastern Nova Scotia especially
Cape Breton.  Rainfall directly from Ophelia is expected over Eastern
Newfoundland beginning early Monday morning.  Expect a 4 to 6 hour
period of heavy rainfall over these regions Monday morning.  40 to 60
millimetres with locally up to 75 millimetres is possible with
rainfall rates up to 20 millimetres/hour.

C. Surge/waves.

Waves will be a concern along the South Coast of Newfoundland Monday.
A range of 5 to 7 metres is likely along the South Coast of
Newfoundland - Fortune bay and east.  Ocean swell will also begin to
reach the Atlantic coast of Nova Scotia tonight and Monday.
Incident swell height of 3 metres breaking in the 4-metre (10-14
foot) range is possible late tonight along the Atlantic coast of Nova
Scotia.  With regard to storm surge, 40 to 60 cm is possible Monday
morning around the Avalon and Burin peninsulas.  Since high tides
will occur early in the afternoon and the storm is forecast to pass
the Avalon in the morning this should not pose significant problems,
but a slower storm speed or a more northerly track would increase
surge levels.

3. Marine weather impacts and warnings summary.

Hurricane force wind warnings are in effect for southeastern
Maritimes marine areas near and to the right of Ophelia's track.
Gale or storm warnings are in effect for adjacent areas and portions
of the Grand Banks and Eastern Newfoundland waters.  Ophelia's wind
field is relatively compact with its strongest winds confined very
close to its center but will expand away from storm centre on the
south side as it approaches Newfoundland.

Large waves are expected in the offshore - especially to the right
(southeast) and close to Ophelia's track as it moves into Canadian
waters.  Greatest threat for large waves is over Laurentian Fan and
Grand Banks where wave heights of 8 to 10 metres or more are
possible.

Visit weatheroffice.Gc.Ca/hurricane (all in lower case) for the
latest:

- forecast position, central pressure table.
- strength and predicted wind radii table.
- hurricane track information map.
- technical discussion.

Please also refer to the public and marine forecasts and warnings
issued by Environment Canada for your area.

END/COUTURIER/FOGARTY/MERCER/HATT
000
WTNT31 KNHC 022343
TCPAT1

BULLETIN
HURRICANE OPHELIA INTERMEDIATE ADVISORY NUMBER  41A
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL162011
800 PM AST SUN OCT 02 2011

...OPHELIA WEAKENING AS IT MOVES QUICKLY NORTH-NORTHEASTWARD...

..AT 800 PM AST...0000 UTC...THE CENTER OF HURRICANE OPHELIA WAS
LOCATED NEAR LATITUDE 42.4 NORTH...LONGITUDE 59.8 WEST. OPHELIA IS
MOVING TOWARD THE NORTH-NORTHEAST NEAR 33 MPH...54 KM/H. A TURN
TOWARD THE NORTHEAST IS EXPECTED TONIGHT...FOLLOWED BY A TURN
TOWARD THE EAST-NORTHEAST ON MONDAY. ON THE FORECAST TRACK...THE
CENTER OF OPHELIA IS EXPECTED TO PASS NEAR OR OVER THE AVALON
PENINSULA OF NEWFOUNDLAND LATE TONIGHT OR EARLY MONDAY.

MAXIMUM SUSTAINED WINDS HAVE DECREASED TO NEAR 90 MPH...150 KM/H...
WITH HIGHER GUSTS. OPHELIA IS A CATEGORY ONE HURRICANE ON THE
SAFFIR-SIMPSON HURRICANE WIND SCALE. STEADY WEAKENING IS EXPECTED
TO CONTINUE THROUGH MONDAY. HOWEVER...OPHELIA IS EXPECTED TO BE
NEAR HURRICANE STRENGTH WHEN IT PASSES CLOSE TO THE AVALON
PENINSULA. OPHELIA IS FORECAST TO BECOME A POST-TROPICAL CYCLONE
SHORTLY AFTER PASSING SOUTHERN NEWFOUNDLAND.

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 45 MILES...75 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO
260 MILES...415 KM...MAINLY TO THE EAST OF THE CENTER. ENVIRONMENT
CANADA BUOY 44141...LOCATED ABOUT 100 MILES...160 KM...EAST-
NORTHEAST OF THE CENTER OF OPHELIA...RECENTLY REPORTED A SUSTAINED
WIND OF 40 MPH...65 KM/H...AND A WIND GUST OF 54 MPH...86 KM/H.
SABLE ISLAND RECENTLY REPORTED A WIND GUST OF 39 MPH...63 KM/H.

ESTIMATED MINIMUM CENTRAL PRESSURE IS 967 MB...28.56 INCHES.

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