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136
ABNT20 KNHC 250515
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Tue Sep 25 2018

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

The National Hurricane Center is issuing advisories on recently
downgraded Subtropical Depression Leslie, located about 1200 miles
west of the Azores.

A broad area of low pressure located about 300 miles south of Cape
Hatteras, North Carolina, continues to produce showers and
thunderstorms on its north side. Satellite data indicate that the
circulation of the low is elongated and not well organized.
However, this system could still become a tropical depression later
today while it moves northwestward. By tonight and Wednesday,
additional development appears unlikely, due to strong upper-level
winds, while the system moves northward and north-northeastward near
the southeastern United States coast. Regardless of tropical cyclone
formation, this system will likely enhance rainfall across portions
of northeastern South Carolina and eastern North Carolina later
today and tonight. In addition, dangerous surf conditions and rip
currents are expected along portions of the North Carolina coast
today. For more information, please see products from your local
National Weather Service office.
* Formation chance through 48 hours...medium...50 percent.
* Formation chance through 5 days...medium...50 percent.

The remnants of Kirk are located about 1100 miles east of the
Windward Islands and are moving quickly westward at around 25 mph.
This system continues to produce a large area of showers and
thunderstorms, along with winds to gale force on its north side.
However, satellite data indicate that the system still lacks a
closed circulation. This disturbance could redevelop into a
tropical cyclone during the next couple of days before it moves
into an area of highly unfavorable upper-level winds while it
approaches the Caribbean Sea. Interests in the Windward and
Leeward Islands should monitor the progress of this disturbance as
gusty winds and locally heavy rains are likely even if the system
does not redevelop into a tropical cyclone. For more information on
this system, see High Seas Forecasts issued by the National Weather
Service.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 5 days...medium...60 percent.

Subtropical Depression Leslie is forecast to become post-tropical
tonight after it merges with a cold front over the central Atlantic.
After that time, Leslie could reacquire subtropical or tropical
characteristics by the end of the week as it meanders over the
central Atlantic.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 5 days...high...70 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 https://ocean.weather.gov/shtml/NFDHSFAT1.shtml.

$$
Forecaster Cangialosi

Summary for Subtropical Depression Leslie (AT3/AL132018)

...LESLIE EXPECTED TO BECOME A POST-TROPICAL CYCLONE BY TONIGHT...
 As of 5:00 AM AST Tue Sep 25
 the center of Leslie was located near 31.9, -46.2
 with movement SE at 8 mph.
 The minimum central pressure was 1007 mb
 with maximum sustained winds of about 35 mph.

Subtropical Depression Leslie Public Advisory Number 8

Issued at 500 AM AST Tue Sep 25 2018  

978 
WTNT33 KNHC 250837
TCPAT3

BULLETIN
Subtropical Depression Leslie Advisory Number   8
NWS National Hurricane Center Miami FL       AL132018
500 AM AST Tue Sep 25 2018

...LESLIE EXPECTED TO BECOME A POST-TROPICAL CYCLONE BY TONIGHT...


SUMMARY OF 500 AM AST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...31.9N 46.2W
ABOUT 1165 MI...1870 KM WSW OF THE AZORES
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...SE OR 140 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...1007 MB...29.74 INCHES


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


DISCUSSION AND OUTLOOK
----------------------
At 500 AM AST (0900 UTC), the center of Subtropical Depression
Leslie was located near latitude 31.9 North, longitude 46.2 West.
The subtropical depression is moving toward the southeast near 8 mph
(13 km/h).  A faster east to northeast motion is expected later
today and Wednesday, followed by a turn to the north by Wednesday
night.

Maximum sustained winds remain near 35 mph (55 km/h) with higher
gusts.  Leslie is expected to lose its subtropical characteristics
by tonight. Strengthening as an post-tropical cyclone is expected,
and Leslie is forecast to become a large and powerful post-tropical
cyclone by Wednesday with winds approaching hurricane force.

The estimated minimum central pressure is 1007 mb (29.74 inches).


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


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

$$
Forecaster Cangialosi


Subtropical Depression Leslie Forecast Advisory Number 8

Issued at 0900 UTC TUE SEP 25 2018  

711 
WTNT23 KNHC 250837
TCMAT3

SUBTROPICAL DEPRESSION LESLIE FORECAST/ADVISORY NUMBER   8
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132018
0900 UTC TUE SEP 25 2018

THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.

SUBTROPICAL DEPRESSION CENTER LOCATED NEAR 31.9N  46.2W AT 25/0900Z
POSITION ACCURATE WITHIN  30 NM

PRESENT MOVEMENT TOWARD THE SOUTHEAST OR 140 DEGREES AT   7 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1007 MB
MAX SUSTAINED WINDS  30 KT WITH GUSTS TO  40 KT.
12 FT SEAS..240NE 150SE 150SW   0NW.
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 31.9N  46.2W AT 25/0900Z
AT 25/0600Z CENTER WAS LOCATED NEAR 32.2N  46.9W

FORECAST VALID 25/1800Z 32.1N  44.8W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT...  0NE   0SE   0SW 240NW.

FORECAST VALID 26/0600Z 32.7N  41.9W...POST-TROP/EXTRATROP
MAX WIND  50 KT...GUSTS  60 KT.
50 KT...  0NE   0SE   0SW 120NW.
34 KT...  0NE 150SE 180SW 360NW.

FORECAST VALID 26/1800Z 34.5N  40.5W...POST-TROP/EXTRATROP
MAX WIND  60 KT...GUSTS  75 KT.
50 KT...  0NE   0SE  90SW 120NW.
34 KT...270NE 180SE 240SW 360NW.

FORECAST VALID 27/0600Z 36.1N  41.1W...POST-TROP/EXTRATROP
MAX WIND  60 KT...GUSTS  75 KT.
50 KT...150NE 100SE 180SW 240NW.
34 KT...270NE 180SE 270SW 360NW.

FORECAST VALID 28/0600Z 36.0N  45.0W...POST-TROP/EXTRATROP
MAX WIND  55 KT...GUSTS  65 KT.
50 KT...120NE  90SE  90SW 150NW.
34 KT...240NE 180SE 270SW 300NW.

EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 150 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY

OUTLOOK VALID 29/0600Z 35.3N  48.2W...SUBTROPICAL STORM
MAX WIND  55 KT...GUSTS  65 KT.

OUTLOOK VALID 30/0600Z 35.0N  50.0W
MAX WIND  50 KT...GUSTS  60 KT.

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 31.9N  46.2W

NEXT ADVISORY AT 25/1500Z

$$
FORECASTER CANGIALOSI



Subtropical Depression Leslie Forecast Discussion Number 8

Issued at 500 AM AST Tue Sep 25 2018  

977 
WTNT43 KNHC 250837
TCDAT3

Subtropical Depression Leslie Discussion Number   8
NWS National Hurricane Center Miami FL       AL132018
500 AM AST Tue Sep 25 2018

No significant changes have occurred with Leslie overnight.  Deep
convection is generally confined to the eastern half of the
circulation as dry air continues to wrap into the western portion
of the cyclone.  Satellite images indicate that the circulation has
become stretched from north to south, likely due to the approach of
a cold front that is currently located a few hundred miles to the
northwest of Leslie.  The initial intensity is held at 30 kt based
on the earlier ASCAT data.

The cold front is expected to merge with Leslie by tonight, causing
extratropical transition.  While transitioning, Leslie is forecast
to strengthen for a couple of days due to significant baroclinic
forcing, and the NHC intensity forecast takes the peak winds just
below hurricane force at 36 and 48 hours.  Later in the week, the
extratropical system is expected to cut off and gradually lose its
frontal features.  Although this will likely cause some weakening,
it should also allow the system to regain subtropical
characteristics.  The NHC intensity forecast is fairly similar to
the previous one and near the IVCN consensus model.  This forecast
is also in fairly good agreement with the GFS and ECMWF models,
which are usually reliable intensity models for large subtropical
systems like Leslie.  Based on the latest guidance, Leslie is now
expected to transition back to a subtropical cyclone in 96 hours.

Leslie has jogged to the southeast during the past several hours,
but an eastward to northeastward motion is expected during the next
day or so as Leslie makes its extratropical transition.  After that
time, a turn to the north is expected followed by a slow westward
motion when Leslie cuts off from the mid-latitude flow. The models
are in fairly good agreement on this looping motion, and the NHC
track forecast follows the various consensus aids.

FORECAST POSITIONS AND MAX WINDS

INIT  25/0900Z 31.9N  46.2W   30 KT  35 MPH
 12H  25/1800Z 32.1N  44.8W   40 KT  45 MPH
 24H  26/0600Z 32.7N  41.9W   50 KT  60 MPH...POST-TROP/EXTRATROP
 36H  26/1800Z 34.5N  40.5W   60 KT  70 MPH...POST-TROP/EXTRATROP
 48H  27/0600Z 36.1N  41.1W   60 KT  70 MPH...POST-TROP/EXTRATROP
 72H  28/0600Z 36.0N  45.0W   55 KT  65 MPH...POST-TROP/EXTRATROP
 96H  29/0600Z 35.3N  48.2W   55 KT  65 MPH...SUBTROPICAL STORM
120H  30/0600Z 35.0N  50.0W   50 KT  60 MPH

$$
Forecaster Cangialosi


Subtropical Depression Leslie Wind Speed Probabilities Number 8

Issued at 0900 UTC TUE SEP 25 2018


999 
FONT13 KNHC 250837
PWSAT3
                                                                    
SUBTROPICAL DEPRESSION LESLIE WIND SPEED PROBABILITIES NUMBER   8   
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL132018               
0900 UTC TUE SEP 25 2018                                            
                                                                    
AT 0900Z THE CENTER OF SUBTROPICAL DEPRESSION LESLIE WAS LOCATED    
NEAR LATITUDE 31.9 NORTH...LONGITUDE 46.2 WEST WITH MAXIMUM         
SUSTAINED WINDS NEAR 30 KTS...35 MPH...55 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 TUE 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 34...50...64 KT SHOWN WHEN THE 5-DAY              
64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT.                 
                                                                    
                                                                    
  - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - -   
                                                                    
               FROM    FROM    FROM    FROM    FROM    FROM    FROM 
  TIME       06Z TUE 18Z TUE 06Z WED 18Z WED 06Z THU 06Z FRI 06Z SAT
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             18Z TUE 06Z WED 18Z WED 06Z THU 06Z FRI 06Z SAT 06Z SUN
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
$$                                                                  
FORECASTER CANGIALOSI                                               

Subtropical Depression Leslie Graphics


Subtropical Depression Leslie 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Tue, 25 Sep 2018 08:39:39 GMT

Subtropical Depression Leslie 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Tue, 25 Sep 2018 09:22:03 GMT