Monthly Archives: September 2015

Hurricane JOAQUIN Forecast Discussion Number 13 2015-09-30 22:50:22

1443667822
Issued at 1100 PM EDT WED SEP 30 2015


000
WTNT41 KNHC 010250
TCDAT1

HURRICANE JOAQUIN DISCUSSION NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
1100 PM EDT WED SEP 30 2015

Joaquin has rapidly intensified during the past 24 hours with the
satellite presentation continuing to improve this evening.  The eye
has recently become apparent near the center of the very symmetric
central dense overcast.  An Air Force Reserve Hurricane Hunter
aircraft that has been investigating the hurricane this evening has
measured peak 700 mb flight-level winds of 113 kt and 102 kt surface
winds from the SFMR.  These data support an initial intensity of
100 kt, making Joaquin the second major hurricane of the 2015
Atlantic hurricane season. NOTE: Communications problems have
delayed the public release of the Air Force reconnaissance data.

Joaquin continues to move slowly southwestward with an initial
motion estimate of 220/5 kt.  The hurricane is forecast to move
slowly southwestward or west-southwestward for another 24 hours or
so while it remains to the south of a narrow northeast to southwest
oriented ridge.  This ridge is expected to weaken by Friday as a
trough deepens and cuts off over the southeastern United States.
This should cause Joaquin to turn northward within 48 hours. The 18Z
runs of the GFS and HWRF remain in general agreement with the 12Z
UKMET and Canadian models moving Joaquin around the northeastern
portion of the cut-off low and bring the hurricane inland over the
Carolinas or mid-Atlantic states.  The 12Z ECMWF remains the outlier
by showing a track toward the northeast out to sea.  The NHC
forecast continues to follow the trend of the bulk of the guidance
and takes Joaquin toward the U.S east coast. The NHC track is
similar to the previous advisory and is once again east of the
multi-model consensus.  The NOAA G-IV aircraft has recently
completed its synoptic surveillance flight, and data collected
during this mission should be assimilated into the 0000 UTC models,
hopefully reducing the spread of the track guidance.

The upper-level wind pattern over the hurricane is forecast by the
global models to become even more conducive during the next couple
of days.  This favors additional intensification, with the only
possible limiting factors being upwelling of cool SSTs beneath the
slow-moving hurricane and eyewall cycles which could cause some
fluctuations in intensity.  By 72 hours, increasing southwesterly
shear, dry air intrusion, and lower SSTs are expected to cause
gradual weakening.  The updated NHC intensity forecast has been
significantly increased from the previous advisory primarily due to
the higher initial intensity. The official forecast is between the
lower statistical guidance and the higher HWRF during the first
36-48 hours, and is near the SHIPS/LGEM guidance after that time.


KEY MESSAGES:

1.  Preparations to protect life and property within the warning
areas in the Central Bahamas should be completed now.

2.  Confidence in the details of the forecast after 72 hours remains
low, since we have one normally excellent model that keeps Joaquin
far away from the United States east coast.   The range of possible
outcomes is still large, and includes the possibility of a major
hurricane landfall in the Carolinas.

3.  Every effort is being made to provide the forecast models with
as much data as possible.  The NOAA G-IV jet has begun a series of
missions in the storm environment, and the National Weather Service
has begun launching extra balloon soundings.

4.  Because landfall, if it occurs, is still more than three days
away, it's too early to talk about specific wind, rain, or surge
impacts from Joaquin in the United States.  Regardless of Joaquin's
track, strong onshore winds will create minor to moderate coastal
flooding along the coasts of the mid-Atlantic and northeastern
states through the weekend.

5.  A hurricane watch for a portion of the U.S. coast could be
required as early as Thursday evening.

6. Many portions of the eastern U.S. are currently experiencing
heavy rains and gusty winds associated with a frontal system. These
heavy rains are likely to continue for the next few days, even if
the center of Joaquin stays offshore.  The resulting inland flood
potential could complicate preparations for Joaquin should it head
toward the coast, and even more substantial inland flooding is
possible if Joaquin later passes near or over these same areas.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 23.8N  73.1W  100 KT 115 MPH
 12H  01/1200Z 23.5N  73.8W  110 KT 125 MPH
 24H  02/0000Z 23.6N  74.5W  120 KT 140 MPH
 36H  02/1200Z 24.7N  74.8W  120 KT 140 MPH
 48H  03/0000Z 26.6N  74.7W  110 KT 125 MPH
 72H  04/0000Z 31.6N  74.7W   95 KT 110 MPH
 96H  05/0000Z 36.2N  75.6W   85 KT 100 MPH
120H  06/0000Z 38.5N  76.5W   55 KT  65 MPH

$$
Forecaster Brown


http://www.nhc.noaa.gov/text/refresh/MIATCDAT1+shtml/010250.shtml

Hurricane JOAQUIN Forecast Advisory Number 13 2015-09-30 22:49:22

1443667762
Issued at 0300 UTC THU OCT 01 2015


000
WTNT21 KNHC 010249
TCMAT1

HURRICANE JOAQUIN FORECAST/ADVISORY NUMBER  13
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL112015
0300 UTC THU OCT 01 2015

CHANGES IN WATCHES AND WARNINGS WITH THIS ADVISORY...

THE GOVERNMENT OF THE BAHAMAS HAS ISSUED A TROPICAL STORM WARNING
AND A HURRICANE WATCH FOR ANDROS ISLAND.

SUMMARY OF WATCHES AND WARNINGS IN EFFECT...

A HURRICANE WARNING IS IN EFFECT FOR...
* CENTRAL BAHAMAS INCLUDING CAT ISLAND...THE EXUMAS...LONG ISLAND,
RUM CAY...AND SAN SALVADOR
* NORTHWESTERN BAHAMAS INCLUDING THE ABACOS...BERRY ISLANDS,
ELEUTHERA...GRAND BAHAMA ISLAND...AND NEW PROVIDENCE

A HURRICANE WATCH IS IN EFFECT FOR...
* BIMINI
* ANDROS ISLAND

A TROPICAL STORM WARNING IS IN EFFECT FOR...
* SOUTHEASTERN BAHAMAS INCLUDING THE ACKLINS...CROOKED ISLAND,
LONG CAY...THE INAGUAS...MAYAGUANA...AND THE RAGGED ISLANDS...BUT
EXCLUDING THE TURKS AND CAICOS ISLANDS.
* ANDROS ISLAND

A HURRICANE WARNING MEANS THAT HURRICANE CONDITIONS ARE EXPECTED
SOMEWHERE WITHIN THE WARNING AREA. PREPARATIONS TO PROTECT LIFE AND
PROPERTY SHOULD BE RUSHED TO COMPLETION.

A HURRICANE WATCH MEANS THAT HURRICANE CONDITIONS ARE POSSIBLE
WITHIN THE WATCH AREA.

A TROPICAL STORM WARNING MEANS THAT TROPICAL STORM CONDITIONS ARE
EXPECTED SOMEWHERE WITHIN THE WARNING AREA.

HURRICANE CENTER LOCATED NEAR 23.8N  73.1W AT 01/0300Z
POSITION ACCURATE WITHIN  15 NM

PRESENT MOVEMENT TOWARD THE SOUTHWEST OR 220 DEGREES AT   5 KT

ESTIMATED MINIMUM CENTRAL PRESSURE  951 MB
MAX SUSTAINED WINDS 100 KT WITH GUSTS TO 120 KT.
64 KT....... 25NE  30SE  20SW  20NW.
50 KT....... 40NE  60SE  30SW  40NW.
34 KT.......100NE 120SE  80SW  80NW.
12 FT SEAS..210NE 160SE 120SW 180NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT.  RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.

REPEAT...CENTER LOCATED NEAR 23.8N  73.1W AT 01/0300Z
AT 01/0000Z CENTER WAS LOCATED NEAR 23.9N  73.0W

FORECAST VALID 01/1200Z 23.5N  73.8W
MAX WIND 110 KT...GUSTS 135 KT.
64 KT... 30NE  30SE  20SW  20NW.
50 KT... 60NE  60SE  40SW  60NW.
34 KT...120NE 120SE  80SW  80NW.

FORECAST VALID 02/0000Z 23.6N  74.5W
MAX WIND 120 KT...GUSTS 145 KT.
64 KT... 40NE  40SE  30SW  30NW.
50 KT... 70NE  70SE  40SW  50NW.
34 KT...130NE 130SE  80SW 100NW.

FORECAST VALID 02/1200Z 24.7N  74.8W
MAX WIND 120 KT...GUSTS 145 KT.
64 KT... 40NE  40SE  30SW  30NW.
50 KT... 70NE  70SE  50SW  50NW.
34 KT...150NE 150SE  90SW 120NW.

FORECAST VALID 03/0000Z 26.6N  74.7W
MAX WIND 110 KT...GUSTS 135 KT.
50 KT... 80NE  80SE  60SW  70NW.
34 KT...180NE 180SE 100SW 140NW.

FORECAST VALID 04/0000Z 31.6N  74.7W
MAX WIND  95 KT...GUSTS 115 KT.
50 KT... 90NE  90SE  60SW  70NW.
34 KT...210NE 180SE 100SW 160NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 200 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 05/0000Z 36.2N  75.6W
MAX WIND  85 KT...GUSTS 105 KT.

OUTLOOK VALID 06/0000Z 38.5N  76.5W
MAX WIND  55 KT...GUSTS  65 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 23.8N  73.1W

NEXT ADVISORY AT 01/0900Z

$$
FORECASTER BROWN



http://www.nhc.noaa.gov/text/refresh/MIATCMAT1+shtml/010249.shtml