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Atlantic/Gulf of Mexico/Caribbean

Atlantic Tropical Weather Outlook

000
ABNT20 KNHC 221754
TWOAT 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Wed Sep 22 2021

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

The National Hurricane Center is issuing advisories on Tropical 
Depression Peter, located a few hundred miles north of Puerto Rico, 
and on Tropical Depression Rose, located about 1000 miles 
west-northwest of the Cabo Verde Islands. 

Showers and thunderstorms remain well organized in association with 
a tropical wave located several hundred miles southwest of the Cabo 
Verde Islands. In addition, recent satellite wind data indicates 
that the circulation is gradually becoming better defined. If these 
trends continue, a tropical depression could form as soon as this 
afternoon or evening. This system should move westward at 10 to 15 
mph across the eastern and central tropical Atlantic Ocean. 
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...near 100 percent.
* Formation chance through 5 days...high...near 100 percent.

A gale-force, non-tropical low pressure system, the remnants of 
Odette, is located more than 500 miles west-northwest of the 
westernmost Azores. This low is beginning to develop more 
concentrated shower activity and could become a subtropical or 
tropical cyclone as it moves slowly across marginally warm waters 
over the north-central Atlantic Ocean during the next several days. 
However, by the weekend, this system is expected to move south into 
an environment of strong upper-level winds.  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...medium...40 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 
online at ocean.weather.gov/shtml/NFDHSFAT1.php

$$
Forecaster Papin

Summary for Tropical Depression Peter (AT1/AL162021)

...PETER EXPECTED TO BECOME A REMNANT LOW SOON...
 As of 5:00 PM AST Wed Sep 22
 the center of Peter was located near 21.7, -66.7
 with movement NNW at 5 mph.
 The minimum central pressure was 1008 mb
 with maximum sustained winds of about 35 mph.

Tropical Depression Peter Public Advisory Number 17

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT31 KNHC 222055
TCPAT1
 
BULLETIN
Tropical Depression Peter Advisory Number  17
NWS National Hurricane Center Miami FL       AL162021
500 PM AST Wed Sep 22 2021
 
...PETER EXPECTED TO BECOME A REMNANT LOW SOON...
 
 
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...21.7N 66.7W
ABOUT 230 MI...370 KM N OF SAN JUAN PUERTO RICO
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...NNW OR 340 DEGREES AT 5 MPH...7 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Depression Peter
was located near latitude 21.7 North, longitude 66.7 West. The
depression is moving toward the north-northwest near 5 mph (7
km/h). A similar motion with gradual turn to the north is expected
tonight followed by a turn toward the north-northeast tomorrow.
 
Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Gradual weakening is expected during the next couple of days, and
Peter is forecast to degenerate into a remnant low tonight or
tomorrow.
 
The estimated minimum central pressure is 1008 mb (29.77 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
SURF:  Swells generated by Peter are affecting the Virgin Islands, 
Puerto Rico, and Hispaniola, and will continue spreading westward to 
the Bahamas tonight.  These swells could cause life-threatening surf 
and rip current conditions. Please consult products from your local 
weather office.
 
 
NEXT ADVISORY
-------------
Next complete advisory at 1100 PM AST.
 
$$
Forecaster Papin

Tropical Depression Peter Forecast Advisory Number 17

Issued at 2100 UTC WED SEP 22 2021  

000
WTNT21 KNHC 222055
TCMAT1
 
TROPICAL DEPRESSION PETER FORECAST/ADVISORY NUMBER  17
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL162021
2100 UTC WED SEP 22 2021
 
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
 
TROPICAL DEPRESSION CENTER LOCATED NEAR 21.7N  66.7W AT 22/2100Z
POSITION ACCURATE WITHIN  40 NM
 
PRESENT MOVEMENT TOWARD THE NORTH-NORTHWEST OR 340 DEGREES AT   4 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB
MAX SUSTAINED WINDS  30 KT WITH GUSTS TO  40 KT.
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 21.7N  66.7W AT 22/2100Z
AT 22/1800Z CENTER WAS LOCATED NEAR 21.6N  66.7W
 
FORECAST VALID 23/0600Z 22.5N  66.8W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 23/1800Z 23.5N  66.6W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 24/0600Z 24.4N  66.1W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 24/1800Z 25.6N  65.3W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 25/1800Z...DISSIPATED
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 21.7N  66.7W
 
NEXT ADVISORY AT 23/0300Z
 
$$
FORECASTER PAPIN

Tropical Depression Peter Forecast Discussion Number 17

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT41 KNHC 222058
TCDAT1
 
Tropical Depression Peter Discussion Number  17
NWS National Hurricane Center Miami FL       AL162021
500 PM AST Wed Sep 22 2021
 
Peter continues to just barely maintain its classification as a 
tropical cyclone. While the low-level circulation has remained 
intact today, the convection continues to be located well downshear 
to the east. However, there have been a few convective elements 
forming a bit closer to the center recently and that is the 
primarily justification for maintaining advisories on Peter as 
a tropical cyclone this afternoon. The initial intensity is 
maintained at 30 kt given the earlier scatterometer data, though 
this might be generous. Continued strong southwesterly vertical wind 
shear within a dry mid-level environment should ultimately strip the 
remaining convection away from Peter, with the tropical cyclone 
expected to finally peter out as a post-tropical remnant low in the 
next 12 hours. 

The depression has been moving very slowly recently, with an 
estimated north-northwestward motion of 340/4 kt. The cyclone is 
expected to turn northward and then north-northeastward following a 
weakness in the low-level ridge until the system finally opens up 
into a trough, sometime in the 48 to 60 hour period.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 21.7N  66.7W   30 KT  35 MPH
 12H  23/0600Z 22.5N  66.8W   25 KT  30 MPH...POST-TROP/REMNT LOW
 24H  23/1800Z 23.5N  66.6W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  24/0600Z 24.4N  66.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  24/1800Z 25.6N  65.3W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  25/0600Z...DISSIPATED
 
$$
Forecaster Papin

Tropical Depression Peter Wind Speed Probabilities Number 17

Issued at 2100 UTC WED SEP 22 2021                                              

000
FONT11 KNHC 222056
PWSAT1
                                                                    
TROPICAL DEPRESSION PETER WIND SPEED PROBABILITIES NUMBER  17       
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL162021               
2100 UTC WED SEP 22 2021                                            
                                                                    
AT 2100Z THE CENTER OF TROPICAL DEPRESSION PETER WAS LOCATED NEAR   
LATITUDE 21.7 NORTH...LONGITUDE 66.7 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           
        18Z WED 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       18Z WED 06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN 18Z MON
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
$$                                                                  
FORECASTER PAPIN

Tropical Depression Peter Graphics

Tropical Depression Peter 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Wed, 22 Sep 2021 20:56:32 GMT

Tropical Depression Peter 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Wed, 22 Sep 2021 20:56:32 GMT

Summary for Tropical Depression Rose (AT2/AL172021)

...ROSE EXPECTED TO DEGENERATE TO A REMNANT LOW IN THE NEXT DAY OR SO...
 As of 5:00 PM AST Wed Sep 22
 the center of Rose was located near 24.2, -40.2
 with movement WNW at 10 mph.
 The minimum central pressure was 1010 mb
 with maximum sustained winds of about 35 mph.

Tropical Depression Rose Public Advisory Number 15

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT32 KNHC 222036
TCPAT2
 
BULLETIN
Tropical Depression Rose Advisory Number  15
NWS National Hurricane Center Miami FL       AL172021
500 PM AST Wed Sep 22 2021
 
...ROSE EXPECTED TO DEGENERATE TO A REMNANT LOW IN THE NEXT DAY
OR SO...
 
 
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...24.2N 40.2W
ABOUT 1190 MI...1920 KM WNW OF THE CABO VERDE ISLANDS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...1010 MB...29.83 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Depression Rose  
was located near latitude 24.2 North, longitude 40.2 West. The 
depression is moving toward the west-northwest near 10 mph 
(17 km/h).  A northwestward motion is expected tonight, with a turn 
toward the north forecast by Thursday night.  A motion toward the 
northeast is expected on Friday.
 
Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Gradual weakening is expected during the next couple of days, and 
Rose is expected to degenerate to a remnant low pressure area on 
Thursday or Thursday night.
 
The estimated minimum central pressure is 1010 mb (29.83 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
None.
 
 
NEXT ADVISORY
-------------
Next complete advisory at 1100 PM AST.
 
$$
Forecaster Beven

Tropical Depression Rose Forecast Advisory Number 15

Issued at 2100 UTC WED SEP 22 2021  

000
WTNT22 KNHC 222035
TCMAT2
 
TROPICAL DEPRESSION ROSE FORECAST/ADVISORY NUMBER  15
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172021
2100 UTC WED SEP 22 2021
 
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
 
TROPICAL DEPRESSION CENTER LOCATED NEAR 24.2N  40.2W AT 22/2100Z
POSITION ACCURATE WITHIN  20 NM
 
PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT   9 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1010 MB
MAX SUSTAINED WINDS  30 KT WITH GUSTS TO  40 KT.
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 24.2N  40.2W AT 22/2100Z
AT 22/1800Z CENTER WAS LOCATED NEAR 23.8N  39.7W
 
FORECAST VALID 23/0600Z 25.2N  41.3W
MAX WIND  30 KT...GUSTS  40 KT.
 
FORECAST VALID 23/1800Z 26.7N  41.7W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 24/0600Z 28.0N  41.4W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 24/1800Z 29.0N  39.3W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 25/0600Z 29.5N  36.9W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
FORECAST VALID 25/1800Z 30.1N  34.1W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
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 26/1800Z 31.9N  30.4W...POST-TROP/REMNT LOW
MAX WIND  25 KT...GUSTS  35 KT.
 
OUTLOOK VALID 27/1800Z...DISSIPATED
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 24.2N  40.2W
 
NEXT ADVISORY AT 23/0300Z
 
$$
FORECASTER BEVEN

Tropical Depression Rose Forecast Discussion Number 15

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT42 KNHC 222037
TCDAT2
 
Tropical Depression Rose Discussion Number  15
NWS National Hurricane Center Miami FL       AL172021
500 PM AST Wed Sep 22 2021
 
Rose is currently comprised of a swirl of low-level clouds, with 
the only significant convection occurring about 120 n mi southeast 
of the center.  Satellite intensity estimates have decreased, and 
are now 25 kt from TAFB and too weak to classify from SAB.  Based 
mainly on earlier scatterometer data, the initial intensity is held 
at a possibly generous 30 kt.  Rose remain in an area of 
northwesterly shear and upper-level convergence, and dry mid-level 
air has been entraining into the circulation.  The large-scale model 
guidance indicates that the hostile conditions will continue for at 
least another 36 h, and based on model forecasts of convection Rose 
is now expected to degenerate into a remnant low pressure area in 
24 h or less.  It should be noted that the GFS and HWRF models 
suggest the possibility that convection could re-develop in the 
48-96 h period due to the remnant low interacting with an 
upper-level trough.  For now, the intensity forecast will not call 
for re-generation at that time.
 
The initial motion is now west-northwestward or 300/9 kt.  A 
northwestward motion is expected for the next 12-24 hours as Rose or 
its remnants are steered by a mid-level ridge over the eastern 
Atlantic.  After that time, the system is expected to turn 
northward, northeastward, and eventually east-northeastward as it 
becomes steered by a deep-layer trough that includes the remnants 
of Odette.  Since Rose has moved a bit to the west of the previous 
forecast, the guidance and the new forecast track have also shifted 
westward during the first 36 h. The new NHC track is to the east of 
the consensus models for the first 36 h, and close to the consensus 
aids after that time.
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 24.2N  40.2W   30 KT  35 MPH
 12H  23/0600Z 25.2N  41.3W   30 KT  35 MPH
 24H  23/1800Z 26.7N  41.7W   25 KT  30 MPH...POST-TROP/REMNT LOW
 36H  24/0600Z 28.0N  41.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  24/1800Z 29.0N  39.3W   25 KT  30 MPH...POST-TROP/REMNT LOW
 60H  25/0600Z 29.5N  36.9W   25 KT  30 MPH...POST-TROP/REMNT LOW
 72H  25/1800Z 30.1N  34.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 96H  26/1800Z 31.9N  30.4W   25 KT  30 MPH...POST-TROP/REMNT LOW
120H  27/1800Z...DISSIPATED
 
$$
Forecaster Beven

Tropical Depression Rose Wind Speed Probabilities Number 15

Issued at 2100 UTC WED SEP 22 2021                                              

000
FONT12 KNHC 222036
PWSAT2
                                                                    
TROPICAL DEPRESSION ROSE WIND SPEED PROBABILITIES NUMBER  15        
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL172021               
2100 UTC WED SEP 22 2021                                            
                                                                    
AT 2100Z THE CENTER OF TROPICAL DEPRESSION ROSE WAS LOCATED NEAR    
LATITUDE 24.2 NORTH...LONGITUDE 40.2 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           
        18Z WED 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       18Z WED 06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN 18Z MON
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
$$                                                                  
FORECASTER BEVEN

Tropical Depression Rose Graphics

Tropical Depression Rose 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Wed, 22 Sep 2021 20:38:12 GMT

Tropical Depression Rose 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Wed, 22 Sep 2021 20:38:13 GMT

Summary for Tropical Depression Eighteen (AT3/AL182021)

...ANOTHER TROPICAL DEPRESSION FORMS IN THE EASTERN ATLANTIC.. ...EXPECTED TO STRENGTHEN OVER THE NEXT SEVERAL DAYS...
 As of 5:00 PM AST Wed Sep 22
 the center of Eighteen was located near 10.1, -33.9
 with movement W at 15 mph.
 The minimum central pressure was 1008 mb
 with maximum sustained winds of about 35 mph.

Tropical Depression Eighteen Public Advisory Number 1

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT33 KNHC 222100 CCA
TCPAT3
 
BULLETIN
Tropical Depression Eighteen Advisory Number   1...Corrected
NWS National Hurricane Center Miami FL       AL182021
500 PM AST Wed Sep 22 2021

Corrected to include a location reference point for the system. 

...ANOTHER TROPICAL DEPRESSION FORMS IN THE EASTERN ATLANTIC..
...EXPECTED TO STRENGTHEN OVER THE NEXT SEVERAL DAYS...
 
 
SUMMARY OF 500 PM AST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...10.1N 33.9W
ABOUT 2030 MI...3265 KM ESE OF THE NORTHERN LEEWARD ISLANDS
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 15 MPH...24 KM/H
MINIMUM CENTRAL PRESSURE...1008 MB...29.77 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 500 PM AST (2100 UTC), the center of Tropical Depression Eighteen
was located near latitude 10.1 North, longitude 33.9 West. The
depression is moving toward the west near 15 mph (24 km/h) and this
motion is expected to continue for the next day or so followed by a
gradual turn to the west-northwest by Friday.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Strengthening is forecast over the next several days. The
depression is forecast to become a tropical storm by tomorrow, and
could be near hurricane intensity by the weekend.
 
The estimated minimum central pressure is 1008 mb (29.77 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
None.
 
 
NEXT ADVISORY
-------------
Next complete advisory at 1100 PM AST.
 
$$
Forecaster Papin

Tropical Depression Eighteen Forecast Advisory Number 1

Issued at 2100 UTC WED SEP 22 2021  

000
WTNT23 KNHC 222049
TCMAT3
 
TROPICAL DEPRESSION EIGHTEEN FORECAST/ADVISORY NUMBER   1
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182021
2100 UTC WED SEP 22 2021
 
THERE ARE NO COASTAL WATCHES OR WARNINGS IN EFFECT.
 
TROPICAL DEPRESSION CENTER LOCATED NEAR 10.1N  33.9W AT 22/2100Z
POSITION ACCURATE WITHIN  30 NM
 
PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT  13 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1008 MB
MAX SUSTAINED WINDS  30 KT WITH GUSTS TO  40 KT.
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 10.1N  33.9W AT 22/2100Z
AT 22/1800Z CENTER WAS LOCATED NEAR 10.1N  33.2W
 
FORECAST VALID 23/0600Z 10.1N  36.0W
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 30NE   0SE   0SW  30NW.
 
FORECAST VALID 23/1800Z 10.5N  38.6W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT... 50NE   0SE   0SW  40NW.
 
FORECAST VALID 24/0600Z 11.0N  41.1W
MAX WIND  50 KT...GUSTS  60 KT.
50 KT... 20NE   0SE   0SW   0NW.
34 KT... 60NE  30SE   0SW  40NW.
 
FORECAST VALID 24/1800Z 11.7N  43.4W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 20NE  20SE   0SW  20NW.
34 KT... 80NE  50SE  20SW  60NW.
 
FORECAST VALID 25/0600Z 12.4N  45.3W
MAX WIND  70 KT...GUSTS  85 KT.
50 KT... 40NE  30SE  20SW  30NW.
34 KT... 80NE  60SE  40SW  60NW.
 
FORECAST VALID 25/1800Z 13.0N  46.8W
MAX WIND  80 KT...GUSTS 100 KT.
50 KT... 40NE  30SE  20SW  30NW.
34 KT... 90NE  60SE  40SW  80NW.
 
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 26/1800Z 14.2N  49.5W
MAX WIND  90 KT...GUSTS 110 KT.
 
OUTLOOK VALID 27/1800Z 16.0N  52.5W
MAX WIND 100 KT...GUSTS 120 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 10.1N  33.9W
 
NEXT ADVISORY AT 23/0300Z
 
$$
FORECASTER PAPIN

Tropical Depression Eighteen Forecast Discussion Number 1

Issued at 500 PM AST Wed Sep 22 2021  

000
WTNT43 KNHC 222054
TCDAT3
 
Tropical Depression Eighteen Discussion Number   1
NWS National Hurricane Center Miami FL       AL182021
500 PM AST Wed Sep 22 2021

The tropical wave that NHC has been monitoring over the last several 
days has gradually become better organized. The satellite structure 
in particular is quite impressive for a tropical depression, with 
both the 1800 UTC subjective Dvorak estimates from TAFB and SAB 
at T2.5/35 kt. This bigger question, however, was if the system 
possessed a well-defined closed earth-relative circulation. An 
ASCAT-C pass from earlier this morning hinted that the circulation 
was becoming better defined, with the development of westerly 
low-level winds to the south of the convective shield. This westerly 
low-level flow is also confirmed by atmospheric motion vectors 
(AMVs) available from the GOES-16 meso domain over the system. While 
the low-level circulation may still be somewhat broad, it now 
appears to be well-defined enough to mark the formation of a 
tropical cyclone. The initial intensity is set at 30-kt, in 
agreement with peak wind retrievals of 28-30 kt by the earlier 
scatterometer data.  

The initial motion is estimated to be at 270/13 kt, though this is 
somewhat uncertain given that the center has only recently formed. 
An expansive mid-level ridge is located to the north and west of 
the cyclone, which should maintain its heading toward the west, 
though with a gradual gain in latitude as the system approaches 
the western extent of the ridge by day 5. The track guidance is in 
excellent agreement on this track evolution for the first three 
days, with just a bit more spread in the guidance thereafter. The 
ECMWF and its ensemble mean towards the end of the forecast is on 
the left side of the guidance envelope, while the GFS and HWRF 
models are currently on the right side. For the first NHC track 
forecast, I have elected to stay close to the track consensus aids, 
taking a blend of the HCCA and TCVN aids which are near the 
middle of the guidance envelope.

The environment ahead of the tropical depression appears quite 
favorable for intensification. Vertical wind shear is forecast by 
both the ECWMF- and GFS-based SHIPS guidance to stay at or under 10 
kt for the next 3-5 days as the storm traverses warm 28-29 C sea 
surface temperatures. Most of the guidance responds to this 
environment by indicating strengthening, and the NHC intensity 
guidance follows suit, showing a steady increase in intensity 
throughout the forecast period. While it might take a bit of time 
for the formative low-level circulation to become vertically aligned 
with the mid-level center, once that occurs, it is possible a period 
of rapid intensification could occur during the five day forecast. 
The forecast intensity by 120 hours (100 kt) is on the higher end of 
the guidance envelope, but not as high as the latest HWRF or HAFS-B 
forecasts. 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 10.1N  33.9W   30 KT  35 MPH
 12H  23/0600Z 10.1N  36.0W   35 KT  40 MPH
 24H  23/1800Z 10.5N  38.6W   40 KT  45 MPH
 36H  24/0600Z 11.0N  41.1W   50 KT  60 MPH
 48H  24/1800Z 11.7N  43.4W   60 KT  70 MPH
 60H  25/0600Z 12.4N  45.3W   70 KT  80 MPH
 72H  25/1800Z 13.0N  46.8W   80 KT  90 MPH
 96H  26/1800Z 14.2N  49.5W   90 KT 105 MPH
120H  27/1800Z 16.0N  52.5W  100 KT 115 MPH
 
$$
Forecaster Papin

Tropical Depression Eighteen Wind Speed Probabilities Number 1

Issued at 2100 UTC WED SEP 22 2021                                              

000
FONT13 KNHC 222051
PWSAT3
                                                                    
TROPICAL DEPRESSION EIGHTEEN WIND SPEED PROBABILITIES NUMBER   1    
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL182021               
2100 UTC WED SEP 22 2021                                            
                                                                    
AT 2100Z THE CENTER OF TROPICAL DEPRESSION EIGHTEEN WAS LOCATED NEAR
LATITUDE 10.1 NORTH...LONGITUDE 33.9 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           
        18Z WED 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       18Z WED 06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             06Z THU 18Z THU 06Z FRI 18Z FRI 18Z SAT 18Z SUN 18Z MON
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
$$                                                                  
FORECASTER PAPIN

Tropical Depression Eighteen Graphics

Tropical Depression Eighteen 5-Day Uncertainty Track Image
5-Day Uncertainty Track last updated Wed, 22 Sep 2021 20:53:55 GMT

Tropical Depression Eighteen 34-Knot Wind Speed Probabilities
Wind Speed Probabilities last updated Wed, 22 Sep 2021 20:53:55 GMT

Eastern Pacific

Eastern North Pacific Tropical Weather Outlook

339 
ABPZ20 KNHC 221745
TWOEP 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Wed Sep 22 2021

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

A broad and elongated area of low pressure located several hundred 
miles southwest of the southern tip of the Baja California peninsula 
continues to produce disorganized showers and thunderstorms.  
Development of this system during the next day or two, if any, is 
likely to be slow.  After that time, this system is forecast to move 
into an environment of stable air and strong upper-level winds, 
which should inhibit further development.
* Formation chance through 48 hours...low...30 percent. 
* Formation chance through 5 days...low...30 percent.

$$
Forecaster Beven

There are no tropical cyclones at this time.

No tropical cyclones as of Wed, 22 Sep 2021 21:04:21 GMT