Friday, September 13, 2013

Gabrielle heading towards the Maritimes


















000
WTNT42 KNHC 131440
TCDAT2

TROPICAL DEPRESSION GABRIELLE DISCUSSION NUMBER  21
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072013
1100 AM AST FRI SEP 13 2013

AMBIGUITIES FROM AN 0200 UTC ASCAT PASS SUGGEST THAT THERE ARE VERY
LITTLE...IF ANY...NORTHERLY WINDS ON THE WEST SIDE OF THE
CIRCULATION.  GABRIELLE HAS ACCELERATED TOWARD THE NORTH-NORTHEAST
SINCE THAT TIME...REDUCING THE LIKELIHOOD THAT NORTH WINDS ARE
PRESENT.  HOWEVER...A LARGE BURST OF CONVECTION DURING THE PAST 6
HOURS AT LEAST MAKES IT PLAUSIBLE THAT THE CIRCULATION REMAINS
CLOSED...AND SO GABRIELLE IS BEING HELD AS A 30 KT TROPICAL
DEPRESSION FOR THIS ADVISORY.  A SLIGHT INCREASE IN THE MAXIMUM
WINDS IS POSSIBLE TODAY DUE TO BAROCLINIC PROCESSES.

THE FORWARD SPEED OF GABRIELLE HAS INCREASED DURING THE PAST FEW
HOURS...AND THE INITIAL MOTION ESTIMATE IS NOW 020/20. ALL OF THE
DYNAMICAL MODELS SUGGEST THAT THE DEPRESSION WILL CONTINUE TO
ACCELERATE TOWARD THE NORTH-NORTHEAST WHILE IT INTERACTS WITH A
DEEP-LAYER TROUGH LOCATED OVER THE EASTERN UNITED STATES
AND CANADA.  THE GUIDANCE SUGGESTS THAT GABRIELLE WILL OPEN UP INTO
A TROUGH LATER TODAY...ALTHOUGH THE OFFICIAL FORECAST
CONSERVATIVELY SHOWS A 12-HOUR FORECAST POINT.  AFTER
THAT...GABRIELLE OR ITS REMNANTS SHOULD GET ABSORBED BY AN
APPROACHING COLD FRONT. 

FORECAST POSITIONS AND MAX WINDS

INIT  13/1500Z 39.1N  66.5W   30 KT  35 MPH
12H  14/0000Z 43.2N  64.6W   35 KT  40 MPH...POST-TROPICAL
24H  14/1200Z...DISSIPATED

$$
FORECASTER FRANKLIN/ZELINSKY
Shelburne County
12:13 PM ADT Friday 13 September 2013
Rainfall warning for
Shelburne County issued

50 to 80 millimetres of rain is expected by early Saturday morning.

This is a warning that significant rainfall is expected in these regions. Monitor weather conditions..listen for updated statements.

The moisture from Gabrielle has begun to merge with a frontal system this morning and heavy rain has spread across portions of Nova Scotia. This rain will gradually spread eastward today. The heaviest rainfall amounts are expected for Central Nova Scotia where up to 80 millimetres of rain can be expected. Currently there are rainfall warnings in effect for these regions. Stay tuned as rainfall warnings may need to be extended to other Nova Scotia forecast regions this afternoon if there a slight change in the details of this complex weather situation.

Strong southeast winds ahead of this low pressure system will produce Les Suetes winds gusting to 90 km/h from Margaree Harbour to Bay St. Lawrence starting this evening. There winds will ease overnight with the passage of the storm.
WOCN31 CWHX 131145
TROPICAL CYCLONE INFORMATION STATEMENT UPDATED BY THE CANADIAN
HURRICANE CENTRE OF ENVIRONMENT CANADA AT 8:48 AM ADT FRIDAY
13 SEPTEMBER 2013.
---------------------------------------------------------------------
TROPICAL CYCLONE INFORMATION STATEMENT FOR:
      NEWFOUNDLAND
      NOVA SCOTIA
      PRINCE EDWARD ISLAND.

      FOR TROPICAL DEPRESSION GABRIELLE.

      THE NEXT STATEMENT WILL BE ISSUED BY 3:00 PM ADT.

      GABRIELLE BEGINNING TO ACCELERATE NORTHEASTWARD - CURRENTLY
      MERGING WITH FRONTAL SYSTEM - HEAVY RAIN ALREADY AFFECTING NOVA
      SCOTIA.

---------------------------------------------------------------------
==DISCUSSION==
1. SUMMARY OF BASIC INFORMATION AT 9.00 AM ADT.

LOCATION: NEAR 37.9 NORTH 66.8 WEST, OR ABOUT 800 KILOMETRES 
SOUTH-SOUTHWEST OF HALIFAX.

MAXIMUM SUSTAINED WINDS: 56 KM/H.

PRESENT MOVEMENT: NORTH-NORTHEAST AT 28 KM/H.

MINIMUM CENTRAL PRESSURE: 1004 MB.

2. PUBLIC WEATHER IMPACTS AND WARNINGS SUMMARY.

GABRIELLE IS CURRENTLY LOCATED SOUTH OF THE MARITIMES AND IS MOVING 
NORTH-NORTHEASTWARD.  IT WILL CONTINUE TO ACCELERATE TODAY AS IT 
MERGES WITH A COLD FRONT APPROACHING FROM THE WEST.  AS GABRIELLE 
MOVES NORTHWARD, ITS MOISTURE WILL BE DRAWN INTO THE FRONT.
HEAVY RAINFALL FROM THIS MERGING FRONTAL FEATURE IS ALREADY AFFECTING 
NOVA SCOTIA THIS MORNING AND WILL SPREAD ACROSS THE PROVINCE AND INTO 
PEI TODAY.

WHILE GABRIELLE IS AGAIN A TROPICAL DEPRESSION, THIS SLIGHT CHANGE IN 
INTENSITY WILL HAVE NEGLIGIBLE CHANGE ON ITS EFFECTS ON ATLANTIC 
CANADA.  THE STORM CENTRE ITSELF IS ALSO NOT LIKELY TO HAVE MUCH OF A 
DIRECT IMPACT ON THE REGION SINCE MOST OF ITS ENERGY WILL TRANSFER TO 
THE COLD FRONT.  WHAT IS LEFT OF GABRIELLE'S WIND WILL LIKELY CLIP 
EASTERN NOVA SCOTIA TONIGHT.  THE ORIGINAL STORM CENTRE WILL LIKELY 
BE COMPLETELY MERGED WITH THE FRONT BY THE TIME IT REACHES WESTERN
NEWFOUNDLAND BY EARLY SATURDAY.

A. WIND.

AN AREA OF GUSTY WINDS ASSOCIATED WITH THE REMNANTS OF GABRIELLE WILL 
AFFECT EASTERN MAINLAND NOVA SCOTIA AND CAPE BRETON TONIGHT, WITH 
WIND GUSTS UP TO 70 KM/H EXPECTED.  LES SUETES WINDS UP TO 90 KM/H 
ARE FORECAST IN THE LEE OF THE CAPE BRETON HIGHLANDS TONIGHT.
THESE GUSTIER WINDS WILL ALSO MOVE INTO NEWFOUNDLAND BY SATURDAY 
MORNING.

B. RAINFALL.

RAIN (HEAVY AT TIMES) AS ALREADY DEVELOPED OVER NOVA SCOTIA THIS 
MORNING AND SPREAD TO THE REMAINDER OF THE PROVINCE, PRINCE EDWARD
ISLAND, AND ÎLES-DE-LA-MADELEINE DURING THE DAY.  COMPUTER MODELS ARE 
INDICATING THAT THE HEAVIEST RAINFALL RELATED TO GABRIELLE'S REMNANT 
LOW WILL FALL ALONG A SWATH JUST WEST OF AND ROUGHLY PARALLEL TO ITS 
TRACK ACROSS EASTERN NOVA SCOTIA.  RAINFALL WARNINGS ARE IN EFFECT 
FOR PARTS OF CENTRAL AND NORTHEASTERN NOVA SCOTIA, AS WELL AS QUEENS 
AND KINGS COUNTY PEI AND ÎLES-DE-LA-MADELEINE.  LOCAL RAINFALL 
AMOUNTS OF UP TO 70 MILLIMETRES ARE POSSIBLE IN THESE AREAS.
THERE IS A SLIGHT RISK OF 100 MILLIMETRES WITHIN THE SWATH WHICH 
COULD GIVE LOCALIZED FLOODING.  NOTE THAT A CHANGE IN TRACK OR TIMING 
OF THE INTERACTION OF THE FOREMENTIONED FRONT WITH GABRIELLE COULD 
SHIFT THESE MAXIMUM RAINFALL AREAS TO OTHER REGIONS.

THE WEST COAST OF NEWFOUNDLAND AND LABRADOR WILL RECEIVE HEAVY RAIN 
FROM THE APPROACHING FRONT TODAY.  RAIN RELATED TO THE REMNANTS OF 
GABRIELLE WILL BEGIN TO AFFECT SOUTHERN PARTS OF NEWFOUNDLAND TONIGHT 
AND AMOUNTS COULD EXCEED 30-40 MILLIMETRES THROUGH SATURDAY.

C. SURGE/WAVES.

MODERATE WAVE/SURF CONDITIONS ARE LIKELY ALONG THE ATLANTIC COAST OF 
GUYSBOROUGH COUNTY, CAPE BRETON, AND SOUTHERN NEWFOUNDLAND ASSOCIATED 
WITH THE REMNANTS OF GABRIELLE.

3. MARINE WEATHER IMPACTS AND WARNINGS SUMMARY.

GALE WARNINGS ARE IN EFFECT FOR MARITIME WATERS NEAR AND EAST OF 
GABRIELLE'S TRACK.  GALE FORCE WINDS WILL LIKELY DEVELOP AHEAD OF 
GABRIELLE OVER SOUTHERN MARITIME WATERS THIS MORNING, THEN SPREAD 
NORTHWARD DURING THE DAY.  THE STRONGEST WINDS WILL LIKELY OCCUR JUST 
EAST OF THE REMAINING CIRCULATION WHEN IT CROSSES MARITIMES AND 
NEWFOUNDLAND WATERS.

WAVE MODELS SHOW THE POTENTIAL FOR WAVE HEIGHTS OF 4 TO 6 METRES AS 
THE LEFTOVERS OF GABRIELLE MOVE THROUGH.

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/HARTT/COUTURIER/BORGEL

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