Tropical Cyclone Activity

 

Atlantic Tropical Outlook

Satellite loop from NOAA

 

Pacific Tropical Outlook

Satellite loop from NOAA

 

Atlantic/Gulf of Mexico/Caribbean

Atlantic Tropical Weather Outlook

000
ABNT20 KNHC 280513
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 AM EDT Thu Sep 28 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical 
Storm Philippe, located several hundred miles east of the northern 
Leeward Islands.

Central Tropical Atlantic (AL91):
Showers and thunderstorms have changed little in organization in 
association with an area of low pressure located roughly halfway 
between the Cabo Verde Islands and the Lesser Antilles. 
Environmental conditions are forecast to be conducive for 
development, as long as this system remains far enough removed from 
Tropical Storm Philippe to its west. A tropical depression or storm 
is expected to form in the next day or so while the system moves 
northwestward across the central tropical Atlantic. Additional 
information on this system, including gale warnings, can be found in 
High Seas Forecasts issued by the National Weather Service. 
* Formation chance through 48 hours...high...90 percent.
* Formation chance through 7 days...high...90 percent.

&&
High Seas Forecasts issued by the National Weather Service
can be found under AWIPS header NFDHSFAT1, WMO header FZNT01 
KWBC, and online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Bucci

Summary for Tropical Storm Philippe (AT2/AL172023)

...DISORGANIZED PHILIPPE MOVING SLOWLY... ...INTERESTS IN THE NORTHERN LEEWARD ISLANDS, VIRGIN ISLANDS, AND PUERTO RICO SHOULD MONITOR ITS PROGRESS...
 As of 11:00 PM AST Wed Sep 27
 the center of Philippe was located near 18.2, -54.5
 with movement NW at 8 mph.
 The minimum central pressure was 1002 mb
 with maximum sustained winds of about 50 mph.

Tropical Storm Philippe Public Advisory Number 19

Issued at 1100 PM AST Wed Sep 27 2023  

000
WTNT32 KNHC 280235
TCPAT2
 
BULLETIN
Tropical Storm Philippe Advisory Number  19
NWS National Hurricane Center Miami FL       AL172023
1100 PM AST Wed Sep 27 2023
 
...DISORGANIZED PHILIPPE MOVING SLOWLY...
...INTERESTS IN THE NORTHERN LEEWARD ISLANDS, VIRGIN ISLANDS, AND
PUERTO RICO SHOULD MONITOR ITS PROGRESS...
 
 
SUMMARY OF 1100 PM AST...0300 UTC...INFORMATION
-----------------------------------------------
LOCATION...18.2N 54.5W
ABOUT 565 MI...910 KM E OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H
PRESENT MOVEMENT...NW OR 305 DEGREES AT 8 MPH...13 KM/H
MINIMUM CENTRAL PRESSURE...1002 MB...29.59 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
Interests in the northern Leeward Islands, the U.S and
British Virgin Islands, and Puerto Rico should monitor the progress
of this system.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 1100 PM AST (0300 UTC), the center of Tropical Storm Philippe was
located near latitude 18.2 North, longitude 54.5 West. Philippe is
moving toward the northwest near 8 mph (13 km/h).  A slow 
west-northwestward to northwestward motion is forecast during the 
next day or so, followed by a slower general westward motion by this 
weekend. 
 
Maximum sustained winds are near 50 mph (85 km/h) with higher gusts.
Little change in strength is forecast during the next day or so,
with slow weakening forecast this weekend.
 
Tropical-storm-force winds extend outward up to 175 miles (280 km)
primarily to the east of the center. Saildrone (1069) located well 
north-northeast of the center of Philippe has reported a peak 
one-minute wind of 40 mph (65 km/h) and a gust to 48 mph (78 km/h) 
within the past few hours. 
 
The estimated minimum central pressure is 1002 mb (29.59 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
RAINFALL:  Philippe may produce 1 to 3 inches of rain across the 
northern Leeward Islands, the Virgin Islands, and portions of Puerto 
Rico Saturday through Monday.  Heavy rainfall from Philippe may 
produce isolated urban and small stream flooding impacts.
 
 
NEXT ADVISORY
-------------
Next complete advisory at 500 AM AST.
 
$$
Forecaster Brown

Tropical Storm Philippe Forecast Advisory Number 19

Issued at 0300 UTC THU SEP 28 2023  

000
WTNT22 KNHC 280234
TCMAT2
 
TROPICAL STORM PHILIPPE FORECAST/ADVISORY NUMBER  19
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172023
0300 UTC THU SEP 28 2023
 
NOTICE... LAND-BASED TROPICAL CYCLONE WATCHES AND WARNINGS ARE NO
LONGER INCLUDED IN THE TROPICAL CYCLONE FORECAST/ADVISORY...(TCM).
CURRENT LAND-BASED COASTAL WATCHES AND WARNINGS CAN BE FOUND IN THE
MOST RECENTLY ISSUED TROPICAL CYCLONE PUBLIC ADVISORY...(TCP).
 
TROPICAL STORM CENTER LOCATED NEAR 18.2N  54.5W AT 28/0300Z
POSITION ACCURATE WITHIN  30 NM
 
PRESENT MOVEMENT TOWARD THE NORTHWEST OR 305 DEGREES AT   7 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB
MAX SUSTAINED WINDS  45 KT WITH GUSTS TO  55 KT.
34 KT.......150NE 130SE   0SW   0NW.
12 FT SEAS..300NE 180SE 120SW 330NW.
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 18.2N  54.5W AT 28/0300Z
AT 28/0000Z CENTER WAS LOCATED NEAR 18.0N  54.2W
 
FORECAST VALID 28/1200Z 18.7N  55.5W
MAX WIND  45 KT...GUSTS  55 KT.
34 KT...120NE 110SE   0SW   0NW.
 
FORECAST VALID 29/0000Z 19.0N  56.6W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT...100NE  90SE   0SW  20NW.
 
FORECAST VALID 29/1200Z 19.0N  57.6W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT... 90NE  80SE   0SW  20NW.
 
FORECAST VALID 30/0000Z 19.0N  58.6W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT... 60NE  50SE   0SW  10NW.
 
FORECAST VALID 30/1200Z 18.7N  59.4W
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 60NE  50SE   0SW   0NW.
 
FORECAST VALID 01/0000Z 18.5N  60.3W
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 60NE  50SE   0SW   0NW.
 
EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 125 NM
ON DAY 4 AND 175 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY
 
OUTLOOK VALID 02/0000Z 18.5N  62.1W...POST-TROP/REMNT LOW
MAX WIND  30 KT...GUSTS  40 KT.
 
OUTLOOK VALID 03/0000Z 18.5N  63.5W...POST-TROP/REMNT LOW
MAX WIND  30 KT...GUSTS  40 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.2N  54.5W
 
NEXT ADVISORY AT 28/0900Z
 
$$
FORECASTER BROWN

Tropical Storm Philippe Forecast Discussion Number 19

Issued at 1100 PM AST Wed Sep 27 2023  

000
WTNT42 KNHC 280235
TCDAT2
 
Tropical Storm Philippe Discussion Number  19
NWS National Hurricane Center Miami FL       AL172023
1100 PM AST Wed Sep 27 2023
 
Deep convection has persisted around the eastern portion of 
Philippe's circulation this evening, however there is not much 
evidence of curved bands.  The low-level center may have reformed or 
become slightly better defined just to the west of the main 
convective mass since the previous advisory.  There has been no 
recent microwave imagery to gain a better look at the cyclone's 
structure and scatterometer appears likely to miss the center this 
evening.  The latest subjective Dvorak intensity estimates were T3.0 
(45 kt) and T2.5 (35 kt) from TAFB and SAB, respectively.  The 
initial intensity is  held at 45 kt for this advisory, in deference 
to the earlier scatterometer data and latest TAFB estimate.
 
The track forecast for Philippe remains quite complicated, and it is 
very dependent on the future intensity and vertical depth of the 
cyclone.  The current disorganized structure of Philippe and its 
present environment of moderate southwesterly shear is likely to 
inhibit strengthening over the next couple of days. The main 
question is whether Philippe weakens and becomes more vertically 
shallow or if it maintains some vertical coherence during that time. 
If it becomes vertically shallow, Philippe is likely to move 
generally westward or west-southwestward within the low-level 
steering flow.  If it remains more vertically deep, the cyclone is 
likely to move little as it remains to the southeast of a mid-level 
ridge.  Another complicating factor is a disturbance (AL91) to 
Philippe's southeast.  The latest GFS run moves that system close 
enough to Philippe that binary interaction occurs between the two 
systems. However this run appears to have initialized Philippe 
stronger than it actually is, which may have led to the solution 
where Philippe remains the dominate system.  Meanwhile, the 
ECMWF weakens Philippe and keeps more separation between the two 
systems, taking a weaker Philippe westward or west-southwestward.  
The NHC forecast currently favors the latter scenario, but there is 
an unusually large amount of uncertainty in the track and intensity 
forecast.  In general, the guidance is a bit slower this cycle and 
the NHC forecast has been adjusted accordingly.  The new track 
forecast is not as slow as the consensus aids, but is a blend 
of the previous official forecast and the latest consensus models.  
It would not be surprising if additional adjustments to the track 
forecast are required in subsequent advisories. 
 
As mentioned above, moderate southwesterly shear and a slightly 
drier airmass ahead of Philippe are likely to inhibit significant 
convective organization of the cyclone at least during the next day 
or two.  That is likely to cause some gradual weakening, and the NHC 
intensity forecast follows that thinking and calls for the system to 
weaken during that time.  However, there is still a lot of 
uncertainty as to whether Philippe weakens and becomes a remnant low 
later in the period, or moves little and remains a tropical cyclone. 
The latest forecast maintains continuity from the previous few 
advisories and calls for Philippe to become a remnant low, but this 
is a low confidence forecast.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  28/0300Z 18.2N  54.5W   45 KT  50 MPH
 12H  28/1200Z 18.7N  55.5W   45 KT  50 MPH
 24H  29/0000Z 19.0N  56.6W   40 KT  45 MPH
 36H  29/1200Z 19.0N  57.6W   40 KT  45 MPH
 48H  30/0000Z 19.0N  58.6W   40 KT  45 MPH
 60H  30/1200Z 18.7N  59.4W   35 KT  40 MPH
 72H  01/0000Z 18.5N  60.3W   35 KT  40 MPH
 96H  02/0000Z 18.5N  62.1W   30 KT  35 MPH...POST-TROP/REMNT LOW
120H  03/0000Z 18.5N  63.5W   30 KT  35 MPH...POST-TROP/REMNT LOW
 
$$
Forecaster Brown

Tropical Storm Philippe Wind Speed Probabilities Number 19

Issued at 0300 UTC THU SEP 28 2023                                              

000
FONT12 KNHC 280235
PWSAT2
                                                                    
TROPICAL STORM PHILIPPE WIND SPEED PROBABILITIES NUMBER  19         
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172023               
0300 UTC THU SEP 28 2023                                            
                                                                    
AT 0300Z THE CENTER OF TROPICAL STORM PHILIPPE WAS LOCATED NEAR     
LATITUDE 18.2 NORTH...LONGITUDE 54.5 WEST WITH MAXIMUM SUSTAINED    
WINDS NEAR 45 KTS...50 MPH...85 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           
        00Z THU 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       00Z THU 12Z THU 00Z FRI 12Z FRI 00Z SAT 00Z SUN 00Z MON
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             12Z THU 00Z FRI 12Z FRI 00Z SAT 00Z SUN 00Z MON 00Z TUE
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
PONCE PR       34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   2( 3)
 
VIEQUES PR     34  X   X( X)   X( X)   X( X)   X( X)   2( 2)   2( 4)
 
SAINT THOMAS   34  X   X( X)   X( X)   X( X)   1( 1)   2( 3)   2( 5)
 
SAINT JOHN     34  X   X( X)   X( X)   X( X)   1( 1)   2( 3)   3( 6)
 
SAINT CROIX    34  X   X( X)   X( X)   X( X)   X( X)   2( 2)   4( 6)
 
SAINT MAARTEN  34  X   X( X)   X( X)   X( X)   2( 2)   4( 6)   3( 9)
 
SABA           34  X   X( X)   X( X)   X( X)   2( 2)   3( 5)   2( 7)
 
ST EUSTATIUS   34  X   X( X)   X( X)   X( X)   2( 2)   4( 6)   2( 8)
 
ST KITTS-NEVIS 34  X   X( X)   X( X)   X( X)   2( 2)   4( 6)   1( 7)
 
BARBUDA        34  X   X( X)   X( X)   1( 1)   3( 4)   4( 8)   2(10)
 
ANTIGUA        34  X   X( X)   X( X)   X( X)   1( 1)   2( 3)   X( 3)
 
GUADELOUPE     34  X   X( X)   X( X)   X( X)   2( 2)   2( 4)   2( 6)
 
AVES           34  X   X( X)   X( X)   X( X)   1( 1)   1( 2)   1( 3)
 
DOMINICA       34  X   X( X)   X( X)   X( X)   1( 1)   1( 2)   1( 3)
 
$$                                                                  
FORECASTER BROWN

Tropical Storm Philippe Graphics

Tropical Storm Philippe 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Thu, 28 Sep 2023 02:36:29 GMT

Tropical Storm Philippe 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Thu, 28 Sep 2023 03:23:00 GMT

 

Eastern Pacific

Eastern North Pacific Tropical Weather Outlook

000
ABPZ20 KNHC 280514
TWOEP 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Wed Sep 27 2023

For the eastern North Pacific...east of 140 degrees west longitude:

Southwestern East Pacific:
A tropical wave continues to produce an area of disorganized showers 
and thunderstorms well southwest of the southern tip of the Baja 
California peninsula. Some development of this system remains 
possible over the next day or two while it moves generally westward 
at about 15 mph. By late Friday, upper-level winds are forecast to 
become unfavorable for further development before the system moves 
into the Central Pacific basin.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Bucci

There are no tropical cyclones at this time.

No tropical cyclones as of Thu, 28 Sep 2023 06:46:29 GMT