Thursday, October 01, 2015

Major Hurricane Joaquin (Cat 3) a Potential Long Term Threat to the Region Update Three

















000
FXUS61 KCAR 020231
AFDCAR

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CARIBOU ME
1031 PM EDT THU OCT 1 2015

.SYNOPSIS...
HIGH PRESSURE FROM NORTHERN CANADA WILL SLOWLY BUILD SOUTHEAST
TOWARD THE REGION THROUGH FRIDAY...THEN SETTLE ACROSS THE REGION
THIS WEEKEND WHILE A NEARLY STATIONARY FRONTAL SYSTEM REMAINS
S OF THE GULF OF MAINE.

&&

.NEAR TERM /THROUGH FRIDAY NIGHT/...
1025 PM UPDATE: CLOUDS CONTINUE TO EXPAND FURTHER N THAN
PREVIOUSLY FORECAST AND THEREFORE ADJUSTMENTS WERE MADE TO INCLUDE
MORE CLOUDS ACROSS THE NORTHERN SECTIONS OVERNIGHT. MOST OF THE
CLOUDINESS IS ABOVE 12000 FEET. THIS IS VERIFIED BY THE 02Z IRA
SATELLITE AND OBS. THE BEST CLEARING ATTM IS ACROSS THE FAR W &
NW AREAS WHERE TEMPS HAVE DROPPED INTO THE LOWER AND MID 30S WHILE
THE REST OF THE CWA IS IN THE UPPER 30S AND LOWER 40S NE AND LOWER
40S CENTRAL AND DOWNEAST. THESE CLOUDS WILL HOLD OVERNIGHT TEMPS UP
A FEW DEGREES W/THE HELP OF N WIND OF AROUND 10 MPH ESPECIALLY
ACROSS EASTERN AREAS. CLOUDS ARE EXPECTED TO THIN OUT BY SUNRISE
FRIDAY ACROSS THE REST OF NORTHERN MAINE WHICH COULD ALLOW TEMPS
ACROSS EASTERN AREAS TO DROP A FEW DEGREES.

GIVEN THE PRES GRAD BETWEEN STRONG SFC HI PRES TO OUR N AND LOWER
PRES ALG THE STALLED FRONT S OF THE GULF OF ME...IT WILL STAY
BREEZY EVEN AT NGT...WITH LITTLE POTENTIAL OF DECOUPLING AND FROST
POTENTIAL EVEN OVR THE MOST PROTECTED NW VLY LCTNS BOTH TNGT AND
FRI NGT. MEANWHILE...THE AIR MASS OVR THE REGION DURG THIS TM WILL
PRODUCE THE COOLEST HI TEMPS OVR THE REGION SO FAR THIS
FALL...WITH MOST LCTNS NOT RISING ABV THE 50S...WITH NRN HIGHER
TRRN LCTNS LIKELY NOT GETTING OUT OF THE UPPER 40S.

LASTLY...SOME MODEL GUIDANCE SUGGESTS SOME LLVL MOISTURE WORKING
BACK TO THE W FROM THE GULF OF ST LAWRENCE IN THE VICINITY OF THE
ERN CAN MARITIMES BY FRI NGT AS WINDS BECOME MORE ERLY COMPONENT
IN A DEEPER LAYER ABV GROUND...AND THE SUBSIDENCE INVSN INCREASES.
FOR NOW..GIVEN LOW ONSET CONFIDENCE...WE GO WITH PTLY CLDY SKIES N
AND CNTRL...BUT CAN SEE MSLY CLDY SKIES FRI NGT FOR ALL OF THE FA
IF THE CONSENSUS OF MODELS IS ACCURATE WITH THE RETURN OF LLVL
MOISTURE UNDER THE SUBSIDENCE INVSN FRI NGT.

&&

.SHORT TERM /SATURDAY THROUGH SUNDAY/...
CANADIAN HIGH PRESSURE WILL BUILD ACROSS ACROSS QUEBEC SATURDAY
AND SATURDAY NIGHT...THEN MOVE EAST INTO THE MARITIMES ON SUNDAY.
EXPECT PARTLY TO MOSTLY SUNNY SKIES ON SATURDAY WITH HIGHS IN THE
LOW TO MID 50S ACROSS THE REGION. THE HIGH WILL CONTINUE TO BUILD
ACROSS TO OUR NORTH SATURDAY NIGHT WITH MAINLY CLEAR TO PARTLY
CLOUDY SKIES EXPECTED. LOWS SATURDAY NIGHT WILL BE IN THE UPPER
20S TO LOWER 30 NORTH AND MID TO UPPER 30S DOWN EAST. THE HIGH
WILL BEGIN TO MOVE EAST INTO THE CANADIAN MARITIMES ON SUNDAY WITH
CONTINUED DRY WEATHER EXPECTED. HIGHS ON SUNDAY WILL RANGE FROM
THE MID TO UPPER 50S.

&&

.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
HIGH PRESSURE WILL GENERALLY REMAIN ACROSS THE REGION SUNDAY NIGHT
THROUGH MONDAY. ALTHOUGH THERE IS STILL SOME UNCERTAINTY REGARDING
THE EVENTUAL TRACK OF HURRICANE JOAQUIN...LATEST OPERATIONAL
MODELS ARE CONTINUING TO TRACK THE SYSTEM WELL EAST OF THE REGION
THROUGH EARLY NEXT WEEK. HOWEVER, PLEASE REMEMBER TO ALWAYS REFER
TO THE OFFICIAL NHC FORECAST TRACK INFORMATION REGARDING THIS
SYSTEM. HIGH PRESSURE WILL CONTINUE TO BUILD IN TO THE REGION
TUESDAY. A COLD FRONT MAY CROSS THE REGION ON WEDNESDAY WITH THE
CHANCE FOR SHOWERS. HIGH PRESSURE WILL BUILD IN BEHIND THE FRONT
BY THURSDAY. TEMPERATURES THROUGH THE PERIOD WILL BE NEAR NORMAL
THROUGH THE PERIOD.

000
WTNT41 KNHC 020241
TCDAT1

HURRICANE JOAQUIN DISCUSSION NUMBER  17
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM EDT THU OCT 01 2015

The eye of Joaquin contracted in satellite imagery late this
afternoon, but has become obscured by cirrus clouds since that time.
Recent microwave imagery and aircraft observations have not shown
any indications of an eyewall replacement, but the intensity appears
to have leveled off for now.  The aircraft has measured peak 700-mb
flight-level winds of 123 kt and reliable SFMR surface winds of 116
kt, which support an initial wind speed of 115 kt.  Satellite images
show that the outflow is well established over the hurricane and
some additional strengthening is possible during the next 12 hours
or so.  After that time, there could be some fluctuations in
intensity due to eyewall replacement cycles.  Joaquin is forecast to
encounter increasing southwesterly shear in 2 to 3 days, which is
expected to cause some weakening during that time. However, Joaquin
is expected to remain a large and powerful hurricane for the next
several days. The NHC intensity forecast is near the upper-end of
the guidance in the short-term, and is close to the intensity
consensus throughout the remainder of the forecast period.

Recent reconnaissance fixes suggest that Joaquin has turned westward
and slowed down, with an initial motion of 260/3.  The mid- to
upper-level ridge that has been steering Joaquin southwestward is
expected to quickly weaken overnight while a mid- to upper-level
trough over the southeastern United States deepens and cuts off.
This should cause Joaquin to turn northward on Friday, and move
north-northeastward at a faster forward speed Friday night and
Saturday.  The model envelope has again shifted eastward, with the
GFDL and NAVGEM models now joining the other dynamical models which
keep Joaquin offshore of the United States east coast.  This has
required another eastward shift to the NHC forecast, but it still
lies to the west of the multi-model consensus and the most recent
runs of the GFS and ECMWF models.  The updated track is closest to
the GFS ensemble mean.  Additional eastward adjustments could be
required to the official forecast overnight.

Surface and reconnaissance aircraft data indicate that Joaquin's
wind field has expanded during the past 24 hours.  The initial and
forecast wind radii have been adjusted outward accordingly.  The
increase in size has resulted in the issuance of a Tropical Storm
Warning for eastern Cuba where wind gusts above tropical-storm-
force have already been observed.


KEY MESSAGES:

1.  Joaquin's slow motion means that extremely dangerous conditions
will continue over portions of the warning areas in the Bahamas well
into Friday.

2.  The forecast models continue to indicate a track farther away
from the United States east coast and the threat of direct impacts
from Joaquin in the Carolinas and mid-Atlantic states appears to be
decreasing.  However, the threat of impacts in Bermuda has increased
and a Tropical Storm or Hurricane Watch could be required for that
island on Friday.

3.  Efforts to provide the forecast models with as much data as
possible continue, with twice daily NOAA G-IV jet missions in the
storm environment, and extra NWS balloon launches.

4.  Even if Joaquin moves out to sea, strong onshore winds
associated with a frontal system will create minor to moderate
coastal flooding along the coasts of the mid-Atlantic and
northeastern states through the weekend.  In addition, very heavy
rains, not associated with Joaquin, are expected to produce flooding
over portions of the Atlantic coastal states.  Please see products
issued by local NWS Forecast Offices.


FORECAST POSITIONS AND MAX WINDS

INIT  02/0300Z 22.9N  74.6W  115 KT 130 MPH
12H  02/1200Z 23.2N  74.7W  120 KT 140 MPH
24H  03/0000Z 24.7N  74.4W  120 KT 140 MPH
36H  03/1200Z 26.6N  73.4W  115 KT 130 MPH
48H  04/0000Z 29.0N  72.0W  105 KT 120 MPH
72H  05/0000Z 33.4N  70.2W   90 KT 105 MPH
96H  06/0000Z 37.0N  68.3W   70 KT  80 MPH
120H  07/0000Z 42.0N  61.0W   60 KT  70 MPH

$$
Forecaster Brown

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