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000
ABNT20 KNHC 281142
TWOAT

TROPICAL WEATHER OUTLOOK
NWS NATIONAL HURRICANE CENTER MIAMI FL
800 AM EDT SUN AUG 28 2016

For the North Atlantic...Caribbean Sea and the Gulf of Mexico:

The National Hurricane Center is issuing advisories on Hurricane
Gaston, located about 600 miles east of Bermuda.

A weak area of low pressure located near the north coast of central
Cuba continues to produce a large area of disorganized cloudiness
and thunderstorms. Upper-level winds are not conducive for
significant development today while this system moves westward
through the Straits of Florida. The low is expected to move into
the southeastern Gulf of Mexico on Monday, where environmental
conditions could become somewhat more conducive for development.
Regardless of development, heavy rainfall and gusty winds are likely
over portions of the central and northwestern Bahamas, and Cuba
through tonight. Gusty winds and locally heavy rainfall will spread
into parts of southern Florida and the Florida Keys later today.
Interests elsewhere in Florida and the eastern Gulf of Mexico should
continue to monitor the progress of this disturbance. A NOAA
Hurricane Hunter aircraft is scheduled to investigate this system
this afternoon, if necessary.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...medium...60 percent

Shower and thunderstorm activity has increased during the past few
hours in association with an area of low pressure located about 250
miles west of Bermuda. While environmental conditions are only
marginally conducive, some additional development of this system is
possible during the next day or so while it moves west-northwestward
at about 10 mph. As the low approaches the coast of North Carolina
by mid-week, conditions are expected to become unfavorable for
further development. For additional information on this system, see
High Seas Forecasts issued by the National Weather Service. An Air
Force Reserve Hurricane Hunter aircraft is scheduled to investigate
this system this afternoon, if necessary.
* Formation chance through 48 hours...medium...40 percent
* Formation chance through 5 days...medium...40 percent

A tropical wave is expected to move offshore of the west coast of
Africa on Tuesday. Conditions are expected to be favorable for
development of this system later this week while it moves westward
at 15 to 20 mph over the tropical eastern Atlantic.
* Formation chance through 48 hours...low...near 0 percent
* Formation chance through 5 days...medium...60 percent

&&

High Seas Forecasts issued by the National Weather Service can be
found under AWIPS header NFDHSFAT1, WMO header FZNT01 KWBC, and
on the Web at http://www.opc.ncep.noaa.gov/shtml/NFDHSFAT1.shtml.

$$
Forecaster Brennan

Summary for Hurricane GASTON (AT2/AL072016)

...GASTON CONTINUES TO STRENGTHEN...
 As of 5:00 AM AST Sun Aug 28
 the center of GASTON was located near 30.1, -54.6
 with movement NW at 6 mph.
 The minimum central pressure was 975 mb
 with maximum sustained winds of about 90 mph.

Hurricane GASTON Public Advisory Number 23

Issued at 500 AM AST SUN AUG 28 2016  

000
WTNT32 KNHC 280853
TCPAT2

BULLETIN
HURRICANE GASTON ADVISORY NUMBER  23
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016
500 AM AST SUN AUG 28 2016

...GASTON CONTINUES TO STRENGTHEN...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...30.1N 54.6W
ABOUT 620 MI...1000 KM E OF BERMUDA
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 6 MPH...9 KM/H
MINIMUM CENTRAL PRESSURE...975 MB...28.80 INCHES


WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.


DISCUSSION AND 48-HOUR OUTLOOK
------------------------------
At 500 AM AST (0900 UTC), the center of Hurricane Gaston was located
near latitude 30.1 North, longitude 54.6 West.  Gaston is moving
toward the northwest near 6 mph (9 km/h).  A slow northwestward
motion is expected through tonight, followed by a slow northward
or northeastward motion Monday and Monday night.

Maximum sustained winds have increased to near 90 mph (150 km/h)
with higher gusts.  Some additional strengthening is forecast during
the next 48 hours.

Hurricane-force winds extend outward up to 15 miles (30 km) from the
center and tropical-storm-force winds extend outward up to 140 miles
(220 km).

The estimated minimum central pressure is 975 mb (28.80 inches).


HAZARDS AFFECTING LAND
----------------------
None.


NEXT ADVISORY
-------------
Next complete advisory at 1100 AM AST.

$$
Forecaster Brown


Hurricane GASTON Forecast Advisory Number 23

Issued at 0900 UTC SUN AUG 28 2016  

000
WTNT22 KNHC 280852
TCMAT2
 
HURRICANE GASTON FORECAST/ADVISORY NUMBER  23
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016
0900 UTC SUN AUG 28 2016
 
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
 
HURRICANE CENTER LOCATED NEAR 30.1N  54.6W AT 28/0900Z
POSITION ACCURATE WITHIN  20 NM
 
PRESENT MOVEMENT TOWARD THE NORTHWEST OR 325 DEGREES AT   5 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE  975 MB
MAX SUSTAINED WINDS  80 KT WITH GUSTS TO 100 KT.
64 KT....... 15NE  15SE  10SW  15NW.
50 KT....... 60NE  40SE  20SW  40NW.
34 KT.......120NE 120SE  50SW  80NW.
12 FT SEAS..180NE 120SE 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 30.1N  54.6W AT 28/0900Z
AT 28/0600Z CENTER WAS LOCATED NEAR 29.9N  54.5W
 
FORECAST VALID 28/1800Z 30.6N  55.0W
MAX WIND  90 KT...GUSTS 110 KT.
64 KT... 15NE  15SE  10SW  15NW.
50 KT... 60NE  40SE  30SW  40NW.
34 KT...120NE 120SE  60SW  90NW.
 
FORECAST VALID 29/0600Z 31.0N  55.3W
MAX WIND  95 KT...GUSTS 115 KT.
64 KT... 20NE  20SE  15SW  20NW.
50 KT... 70NE  50SE  40SW  50NW.
34 KT...130NE 120SE  80SW 110NW.
 
FORECAST VALID 29/1800Z 31.3N  55.2W
MAX WIND  90 KT...GUSTS 110 KT.
64 KT... 30NE  30SE  20SW  30NW.
50 KT... 70NE  60SE  50SW  60NW.
34 KT...140NE 120SE  90SW 110NW.
 
FORECAST VALID 30/0600Z 31.9N  54.3W
MAX WIND  90 KT...GUSTS 110 KT.
50 KT... 70NE  70SE  50SW  60NW.
34 KT...140NE 130SE 100SW 110NW.
 
FORECAST VALID 31/0600Z 33.3N  51.2W
MAX WIND  90 KT...GUSTS 110 KT.
50 KT... 80NE  80SE  70SW  60NW.
34 KT...140NE 150SE 120SW 110NW.
 
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 01/0600Z 35.8N  46.2W
MAX WIND  80 KT...GUSTS 100 KT.
 
OUTLOOK VALID 02/0600Z 38.5N  39.5W
MAX WIND  70 KT...GUSTS  85 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 30.1N  54.6W
 
NEXT ADVISORY AT 28/1500Z
 
$$
FORECASTER BROWN
 
 

Hurricane GASTON Forecast Discussion Number 23

Issued at 500 AM AST SUN AUG 28 2016  

000
WTNT42 KNHC 280857
TCDAT2

HURRICANE GASTON DISCUSSION NUMBER  23
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016
500 AM AST SUN AUG 28 2016

For much of the night, there was little overall change in the
organization of Gaston.  A ragged eye had occasionally been seen
in infrared satellite imagery, and an 0529 UTC AMSR microwave
overpass detected an eye that was open over the southwestern
quadrant. However, within the past hour or so, the eye has become a
little more apparent, with some cooling to the surrounding cloud
tops. As a result, the initial intensity has been increased to 80
kt, which is slightly above the latest subjective Dvorak estimates
because of the recent increase in organization.

Gaston is forecast to remain in a low-shear environment and
over warm water during the next 24 hours, which should allow for
additional intensification.  After that time, the NHC forecast shows
a leveling-off of Gaston's intensity due to the possibility of
upwelling of cooler water resulting from the expected slow motion
of the hurricane. Later in the period, increasing in southwesterly
shear is likely to cause some weakening, but Gaston is predicted to
remain a hurricane during the entire 5-day forecast period.

The forward motion of the hurricane appears to be slowing down
as anticipated, with recent satellite fixes indicating an initial
motion of 325/5 kt.  Gaston should continue to decelerate during
the next day or so as it remains within an area of weak steering
flow.  In a 2 to 3 days, a mid-latitude trough is forecast to dig
southward off the northeastern United States coast, which should
begin to steer Gaston northeastward, but a a slower speed than that
of typical recurving hurricanes over the North Atlantic.  The track
guidance is in good agreement on this scenario, and the NHC track is
near the consensus of the dynamical models.

FORECAST POSITIONS AND MAX WINDS

INIT  28/0900Z 30.1N  54.6W   80 KT  90 MPH
 12H  28/1800Z 30.6N  55.0W   90 KT 105 MPH
 24H  29/0600Z 31.0N  55.3W   95 KT 110 MPH
 36H  29/1800Z 31.3N  55.2W   90 KT 105 MPH
 48H  30/0600Z 31.9N  54.3W   90 KT 105 MPH
 72H  31/0600Z 33.3N  51.2W   90 KT 105 MPH
 96H  01/0600Z 35.8N  46.2W   80 KT  90 MPH
120H  02/0600Z 38.5N  39.5W   70 KT  80 MPH

$$
Forecaster Brown


Hurricane GASTON Wind Speed Probabilities Number 23

Issued at 0900 UTC SUN AUG 28 2016


000
FONT12 KNHC 280853
PWSAT2
                                                                    
HURRICANE GASTON WIND SPEED PROBABILITIES NUMBER  23                
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL072016               
0900 UTC SUN AUG 28 2016                                            
                                                                    
AT 0900Z THE CENTER OF HURRICANE GASTON WAS LOCATED NEAR LATITUDE   
30.1 NORTH...LONGITUDE 54.6 WEST WITH MAXIMUM SUSTAINED WINDS NEAR  
80 KTS...90 MPH...150 KM/H.                                         
                                                                    
Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH)                  
   ATLANTIC STANDARD TIME (AST)...SUBTRACT 4 HOURS FROM Z TIME      
   EASTERN  DAYLIGHT TIME (EDT)...SUBTRACT 4 HOURS FROM Z TIME      
   CENTRAL  DAYLIGHT TIME (CDT)...SUBTRACT 5 HOURS FROM Z TIME      
                                                                    
WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS                 
                                                                    
CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST     
   ...34 KT (39 MPH... 63 KM/H)...                                  
   ...50 KT (58 MPH... 93 KM/H)...                                  
   ...64 KT (74 MPH...119 KM/H)...                                  
FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS               
                                                                    
PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE               
    OP  IS THE PROBABILITY OF THE EVENT BEGINNING DURING            
        AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY)               
   (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN           
        06Z SUN AND THE FORECAST HOUR (CUMULATIVE PROBABILITY)      
                                                                    
PROBABILITIES ARE GIVEN IN PERCENT                                  
X INDICATES PROBABILITIES LESS THAN 1 PERCENT                       
PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN
THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT.             
PROBABILITIES FOR 64 KT ARE SHOWN WHEN THE 5-DAY CUMULATIVE         
PROBABILITY IS AT LEAST 1 PERCENT.                                  
                                                                    
                                                                    
  - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - -   
                                                                    
               FROM    FROM    FROM    FROM    FROM    FROM    FROM 
  TIME       06Z SUN 18Z SUN 06Z MON 18Z MON 06Z TUE 06Z WED 06Z THU
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             18Z SUN 06Z MON 18Z MON 06Z TUE 06Z WED 06Z THU 06Z FRI
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
SANTA CRUZ AZO 34  X   X( X)   X( X)   X( X)   X( X)   X( X)   8( 8)
 
$$                                                                  
FORECASTER BROWN                                                    

Hurricane GASTON Graphics


Hurricane GASTON 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Sun, 28 Aug 2016 08:54:21 GMT

Hurricane GASTON 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Sun, 28 Aug 2016 09:06:40 GMT