Wednesday, September 04, 2019

Hurricane Dorian regains Major Hurricane Status (Category Three)






























000
FXUS61 KCAR 050414
AFDCAR

Area Forecast Discussion
National Weather Service Caribou ME
1214 AM EDT Thu Sep 5 2019

.SYNOPSIS...
High pressure will build across the area into Friday. Tropical
Cyclone Dorian is expected to track south of the Gulf of Maine
Friday night into Saturday. High pressure will build toward the
region early next week....

....SHORT TERM /THURSDAY NIGHT THROUGH SATURDAY/...

High pressure pushes south into Northern Maine tonight and
early Friday. Chilly night Thursday night with patchy frost
possible in Northern Maine. High pressure pushes east of the
area on Friday but remaining dry with highs in the 60s.

Then attention turns to Dorian. Models are in pretty good
agreement on a track to Nova Scotia late Saturday. Overall model
trend in the last 24 hours has been a bit of westward trend,
which would bring Dorian just a little closer to us. Did raise
PoPs/QPF/Wind for Downeast some late Saturday based on this
model trend. If Dorian does impact us, best shot at the
strongest winds would be Downeast, especially Washington County,
where gusts over 40 mph and power outages are a possibility.
Right now the western edge of the rain is likely to make it to
far Eastern Maine, but probably won`t make it west to Moosehead
Lake. All of this is of course very sensitive to small changes
in the track of Dorian. For the official track information on
Dorian, refer to the National Hurricane Center at nhc.noaa.gov.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...

Dorian kicks out rapidly Saturday night with diminishing winds
into Sunday. Generally looking dry Sunday through Tuesday with
high pressure building in and temperatures a bit below average.
Next system on track for around Wednesday, though models
disagreement quite a bit on its timing and strength.....

000
WTNT45 KNHC 050255
TCDAT5

Hurricane Dorian Discussion Number  47
NWS National Hurricane Center Miami FL       AL052019
1100 PM EDT Wed Sep 04 2019

Satellite imagery indicated that the cloud pattern associated with
Dorian was a little better organized with a clear eye surrounded
by a ring of very deep convection. This trend was confirmed with
data from both NOAA and Air Force reconnaissance planes, which
measured a minimum central pressure of 955 mb. SFMR and flight-level
winds support an initial intensity of 100 kt. In fact, Dvorak
numbers also call for 100 kt.

Dorian could maintain this intensity for about 12 hours or so,
but guidance is showing shear increasing, and that should result
in gradual weakening. The intensity forecast is basically the same
as the previous advisory, keeping Dorian at the border of category 2
or 3 intensity as it moves near the southeast coast of the United
States. This forecast is consistent with the intensity models, which
unanimously gradually weaken the cyclone. On the other hand, the
wind field is expected to gradually expand during the next several
days until the cyclone becomes extratropical near Atlantic Canada.

Aircraft fixes yield a northward motion or 010 degrees at 6 kt.
Dorian is already recurving as it is becoming steered by the south-
southwesterly flow ahead of an eastward-moving mid-level trough. The
track guidance is tightly clustered, and the NHC forecast follows
very closely the multi-model consensus. No significant change to
the previous track forecast was necessary. The forecast motion
should bring the core of Dorian near the coast of South Carolina
during the next 6 to 12 hours and over the Outer Banks of North
Carolina between 24 and 36 hours.

Since the NHC track prediction continues to take Dorian dangerously
close to the southeast U.S. coast, all interests from Georgia
to the Carolinas should remain vigilant to the possibility of
experiencing destructive winds, flooding rains, and life-
threatening storm surges from this hurricane.

Key Messages:

1. Life-threatening storm surge and dangerous winds are expected
along portions the coasts of Georgia, South Carolina, and North
Carolina, and portions of southeast Virginia and the southern
Chesapeake Bay, regardless of the exact track of Dorian's center.
Water levels could rise well in advance of the arrival of strong
winds. Residents in these areas should follow advice given by local
emergency officials.

2. Flash flooding will become increasingly likely across coastal
Georgia into the eastern Carolinas overnight. On Thursday, there is
a high risk of flash flooding over coastal sections of the
Carolinas, where significant, life-threatening, flash flooding is
expected.


FORECAST POSITIONS AND MAX WINDS

INIT  05/0300Z 31.3N  79.6W  100 KT 115 MPH
 12H  05/1200Z 32.2N  79.4W  100 KT 115 MPH
 24H  06/0000Z 33.6N  78.1W   90 KT 105 MPH
 36H  06/1200Z 35.2N  75.9W   85 KT 100 MPH...OVER NC OUTER BANKS
 48H  07/0000Z 37.5N  72.2W   80 KT  90 MPH
 72H  08/0000Z 45.0N  62.8W   65 KT  75 MPH
 96H  09/0000Z 53.5N  52.5W   50 KT  60 MPH...POST-TROP/EXTRATROP
120H  10/0000Z 58.0N  38.5W   40 KT  45 MPH...POST-TROP/EXTRATROP

$$
Forecaster Avila

FXCN31 CWHX 050000
Tropical cyclone technical information statement issued by the
Canadian Hurricane Centre of Environment Canada at 8.41 PM ADT
Wednesday 04 September 2019.

The next statement will be issued by 3.00 AM ADT

1. Current position, strength, central pressure and motion

At 9.00 PM ADT, hurricane Dorian was located near latitude 30.7 N and
longitude 79.8 W, about 129 nautical miles or 239 km south of
Charleston. Maximum sustained winds are estimated at 95 knots (176
km/h) and central pressure at 961 MB. Dorian is moving north at 8
knots (15 km/h).

2. Forecast position, central pressure and strength

Date     time     lat    lon   MSLP  Max wind
          ADT                    MB  kts  kmh
Sep 04  9.00 PM  30.7N  79.8W   961   95  176
Sep 05  9.00 AM  31.9N  79.6W   968   90  167
Sep 05  9.00 PM  33.2N  78.4W   970   85  157
Sep 06  9.00 AM  35.0N  75.9W   970   85  157
Sep 06  9.00 PM  37.4N  72.4W   967   85  157
Sep 07  9.00 AM  40.3N  68.2W   962   80  148
Sep 07  9.00 PM  43.8N  63.8W   955   75  139
Sep 08  9.00 AM  48.1N  59.4W   960   70  130
Sep 08  9.00 PM  51.8N  53.3W   965   65  120 post-tropical
Sep 09  9.00 AM  55.1N  46.5W   971   50   93 post-tropical


3. Technical discussion

A. Analysis

Hurricane Dorian has displayed a better organized eye structure over
the past few hours. The latest hurricane aircraft reconnaissance
flight found a slight drop in the central pressure and increase in
the flight level winds. The intensity has increased slightly to 95
knots with the storm moving in a northerly drection of 8 knots.
Dorian should remain in a favourable environment under light to
moderate wind shear and warm sea surface temperatures over the next
day.

B. Prognostic

Hurricane Dorian is expected to continue along the western
sub-tropical ridge and then begin recurving to the northeast,
possibly skirting the south and North Carolina coastlines before
moving offshore of Cape Hatteras on Friday. Dorian is then expected
to increase its forward speed as the storm gets picked up in the
westerlies ahead of a mid-latitude trough moving over the eastern us
on Friday. Track guidance indicates that the system will move off to
the northeast into the Canadian maritime waters on Saturday morning,
and will track near or south of Nova Scotia Saturday night and
through Newfoundland on Sunday. The storm is expected to become
post-tropical system with hurricane or near hurricane force winds as
it crosses Newfoundland.

Track guidance has been relatively consistent for the trajectory of
Dorian, but there remains a lot of uncertainty in the forward speed
and intensity as it tracks off the North Carolina coast and
approaches Atlantic Canada.

C. Predicted wind radii (NM)

Time          gales           storms            hurricane
         NE  SE  SW  NW    NE  SE  SW  NW    NE  SE  SW  NW
05/00Z  160 140 100 130    95  75  60  85    60  50  40  50
05/12Z  160 145 105 115    85  80  60  75    60  50  40  50
06/00Z  160 155 110 100    80  80  60  65    55  50  40  50
06/12Z  170 165 125 105    85  85  65  70    50  50  40  50
07/00Z  190 180 150 130    90  90  70  80    50  50  40  50
07/12Z  215 195 175 160   100 100  80  80    60  50  50  40
08/00Z  220 200 180 170   100 100  80  80    70  50  30  30
08/12Z  215 200 180 170   110  95  55  70    70  50  10  30
09/00Z  210 200 180 170   120  90  55  40    30  30  10  10
09/12Z  210 200 180 120    90  80  55   0     0   0   0   0

END/MERCER/MCARTHUR

8:37 PM ADT Wednesday 04 September 2019
Tropical cyclone information statement for:

New Brunswick:

Acadian Peninsula
Fredericton and Southern York County
Fundy National Park
Grand Lake and Queens County
Grand Manan and Coastal Charlotte County
Kent County
Kouchibouguac National Park
Miramichi and area
Moncton and Southeast New Brunswick
Oromocto and Sunbury County
Saint John and County
St. Stephen and Northern Charlotte County
Stanley - Doaktown - Blackville Area
Sussex - Kennebecasis Valley and Kings County
Newfoundland and Labrador:

Cartwright to Black Tickle
Eagle River
Newfoundland
Norman Bay to Lodge Bay
Red Bay to L'Anse-au-Clair
Nova Scotia

Prince Edward Island

Québec - south:

Anticosti
Blanc-Sablon
Chevery
Îles-de-la-Madeleine
For Hurricane Dorian.

The next information statement will be issued by 03:00 a.m. ADT.

Hurricane Dorian is expected to move into Atlantic Canada this
weekend.

1. Summary of basic information at 09:00 p.m. ADT.

Location: 30.7 North 79.8 West.

About 239 kilometres south of Charleston.

Maximum sustained winds: 176 kilometres per hour.

Present movement: north at 15 kilometres per hour.

Minimum central pressure: 961 millibars.

2. Public weather impacts and warnings summary.

High winds and rainfall will be the major impacts, especially for the southern Maritimes and Newfoundland. There will also be high waves, especially for the Atlantic coasts of Nova Scotia and Newfoundland. Finally, there is a chance that storm surge may affect parts of Nova Scotia and Newfoundland.

a. Wind.

Most regions will see some tropical storm force winds, and near and south of the forecast track winds should reach hurricane force. As the storm moves into the Maritimes, there is the possibility of hurricane force northwesterlies behind the storm. Wind impacts may be enhanced by foliage on the trees, and may cause power outages.

b. Rainfall.

Rainfall will be significant, especially north and west of Dorian's track. This suggests highest rainfall amounts are likely for the southern Maritimes and parts of Newfoundland, but some rain is likely over most regions. Amounts in excess of 50 mm are possible north and west of Dorian, and localised amounts near 100 mm are possible, especially for Nova Scotia.

c. Surge/Waves.

There will also be some rough and pounding surf, especially for parts of Nova Scotia and Newfoundland. Large waves will reach southwestern Nova Scotia on Saturday and build to near 10 metres over eastern Nova Scotia Saturday night. These waves will likely reach southern Newfoundland by Sunday morning. Waves near or higher than 5 metres will impact north facing coasts of the Gulf of St. Lawrence. Note that waves will break higher along the coast, and rip currents are likely. Please exercise extreme caution. Storm surge is possible, mainly for parts of Nova Scotia, Prince Edward Island, and Newfoundland, but it is too early to be specific about which portions of the coastline may be affected.

3. Marine weather impacts and warnings summary.

As Hurricane Dorian moves into our waters, there is a good chance of hurricane force southeasterlies near and south of the track, mainly over southern Atlantic forecast waters. As the storm moves into the Maritimes, storm to hurricane force northwesterlies may develop behind it. Waves in excess of 12 metres are likely south of the storm track, beginning late Saturday over southwestern waters and approaching southern Newfoundland Sunday morning.

Forecasters: Couturier, Mercer, McArthur.

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