Tropical Weather Discussion
NWS National Hurricane Center Miami FL
0005 UTC Wed Aug 23 2023

Tropical Weather Discussion for North America, Central America
Gulf of Mexico, Caribbean Sea, northern sections of South
America, and Atlantic Ocean to the African coast from the
Equator to 31N. The following information is based on satellite
imagery, weather observations, radar and meteorological analysis.

Based on 1800 UTC surface analysis and satellite imagery
through 2100 UTC.

…SPECIAL FEATURES…

Tropical Depression Harold is centered near 27.6N 99.3W at
22/2100 UTC or 10 nm E of Laredo Texas, moving WNW at 18 kt.
Estimated minimum central pressure is 999 mb. Maximum sustained
wind speed is 30 kt with gusts to 40 kt. Seas are up to 11 ft.
Scattered moderate conveciton is noted north of 27N and west of
98W. The depression is moving toward the west-northwest near 18
kt, and this motion should continue until it dissipates on
Wednesday. Harold is expected to produce rainfall amounts of 2 to
4 inches, with isolated higher amounts of 6 inches, across South
Texas through early Wednesday. Across Mexico, rainfall amounts
of 4 to 6 inches, with local amounts of 10 inches, are expected
across portions of northern Coahuila and northern Nuevo Leon
through Wednesday. Scattered instances of flash flooding are
expected.

Tropical Storm Franklin is centered near 15.8N 71.4W at 22/2100
UTC or 180 nm SSW of Santo Domingo Dominican Republic, moving NW
at 6 kt. Estimated minimum central pressure is 1002 mb. Maximum
sustained wind speed is 35 kt with gusts to 45 kt. Seas are up to
18 ft. Scattered moderate and isolated strong convection is
noted within 180 NM of its center. A turn toward the north is
expected tonight, followed by a turn toward the northeast by
Thursday. On the forecast track, the center of Franklin is
expected to approach the southern coast of Hispaniola tonight,
cross the island on Wednesday, and then emerge over the
southwestern Atlantic waters late Wednesday. Little change in
strength is forecast during the next couple of days while
Franklin moves near and across Hispaniola. Some strengthening is
possible late Thursday into Friday as Franklin moves farther
northeast over the southwestern Atlantic waters. Franklin is
expected to produce rainfall totals of 5 to 10 inches, with
isolated higher amounts up to 15 inches across portions of
Hispaniola through Wednesday. Rainfall totals of 1 to 3 inches,
with storm total maxima of 6 inches, are expected across Puerto
Rico and Vieques into Thursday.

Please read the latest HIGH SEAS FORECAST issued by the National
Hurricane Center at website –
https://www.nhc.noaa.gov/text/MIAHSFAT2.shtml and the latest
Franklin and Harold NHC Forecast/Advisory and Public Advisory at
www.hurricanes.gov for more details.

…TROPICAL WAVES…

A tropical wave has its axis along 31W extending from 05N-21N
with a 1008 mb low centered at 17N31W. Scattered moderate
convection is noted from 11N-19N between 30W-40W. Environmental
conditions now appear only marginally conducive for gradual
development of this system – also known as AL92, but a tropical
depression could still form later this week or over the weekend
while it moves west-northwestward to northwestward across the
eastern and central Atlantic.

…MONSOON TROUGH/ITCZ…

The monsoon trough passes through the coastal border areas of
Senegal and Mauritania near 16N16W, to the AL92 1008 mb low
pressure center at 17N31W, to 13N43W. The ITCZ continues from
13N43W to 13N53W. Scattered moderate convection is noted from
11N-19N between 30W-40W and from 10N-13N east of 21W.

The E Pacific monsoon trough extends from Costa Rica at 10N83W to
13N77W in the Caribbean. Scattered moderate and isolated strong
convection is noted south of 14N and west of 78W.

…GULF OF MEXICO…

The effects of Tropical Depression HAROLD are in the NW Gulf of
Mexico. Please, read the SPECIAL FEATURES section, for details.
Elsewhere, fresh NE winds cover the Straits of Florida with winds
moderate or lighter over the remainder of the Gulf. Seas away
from Harold are 4-6 over the Straits of Florida and the central
Gulf, with 2-4 ft in the NE Gulf of SW Gulf.

For the forecast, Harold will move farther inland to 28.7N
101.9W Wed morning and dissipate Wed afternoon. Numerous showers
and thunderstorms with strong gusty winds in the wake of Harold
will continue to move toward the NW Gulf through Wed. Conditions
will gradually improve in the NW Gulf beginning Wed as high
pressure builds in over the area from the E.

…CARIBBEAN SEA…

The effects of Tropical Storm FRANKLIN are in the NW Gulf of
Mexico. Please, read the SPECIAL FEATURES section, for details.
Elsewhere, the trades are moderate to fresh, except for moderate
to fresh SW winds in the SW Caribbean and just north of Colombia.
Seas away from Franklin are 3-6 ft.

For the forecast, Franklin will move to near 17.0N 71.3W late
tonight, inland the Dominican Republic near 19.1N 70.9W Wed
afternoon, then back over water near 20.9N 70.3W late Wed night
with maximum sustained winds 35 kt gusts 45 kt, and begin to
gradually intensify as it moves farther away from the Caribbean
through the end of the week. Gert is now a post-tropical low near
17N60W with pressure of 1008 mb. The low will continue to weaken
as it moves to near 19N60W early Wed and drift slightly
southeastward Thu, dissipating by early Thu evening. Conditions
in the Caribbean will improve Wed night into early Thu.

…ATLANTIC OCEAN…

Two weak lows are present: Post-Tropical Cyclone Emily at 24N47W
with 1011 mb central pressure and Post-Tropical Cyclone Gert at
18N60W with 1009 mb central pressure. PTC Emily has fresh to
strong winds, seas 8-9 ft, and scattered moderate convection
within 180 NM of its center in the NE semicircle. PTC Gert only
has moderate winds, though it still has scattered moderate
convection within 90 NM of its center in the E semicircle.
Elsewehre, winds are moderate or lighter across the basin with
seas 4-6 ft.

For the forecast, Tropical Storm Franklin is expected to move
back over water near 20.9N 70.3W late Wed night with maximum
sustained winds 35 kt gusts 45 kt, and begin to gradually
intensify as it moves to near 22.0N 69.3W Thu afternoon, to near
22.5N 68.2W late Thu night night with maximum sustained winds 45
kt gusts 55 kt, to near 22.9N 67.3W Fri afternoon with maximum
sustained winds 50 kt gusts 60 kt, to near 24.3N 66.7W Sat
afternoon with maximum sustained winds 60 kt gusts 75 kt and
reach hurricane strength near 27.6N 67.7W Sun afternoon with
maximum sustained winds 75 kt gusts 90 kt. The remnant low of
former tropical cyclone Gert is expected to reach near 19N60W by
early Wed, with little or no impacts on winds and seas. A cold
front is expected to move across the waters E of northern Florida
Wed through Thu followed by fresh to strong northeast winds and
building seas.

$$
Landsea

000
WTNT43 KNHC 222045
TCDAT3
 
Tropical Storm Franklin Discussion Number   9
NWS National Hurricane Center Miami FL       AL082023
500 PM EDT Tue Aug 22 2023
 
Franklin is not a healthy tropical cyclone--and there is still some
question if it even is a tropical cyclone.  A NOAA Hurricane
Hunter aircraft investigating the system found a broad low-level
cyclonic wind field exposed to the west of the deep convection, but
this feature is well to the west of where we would have expected the
center to be.  At the same time, developing deep convection with
some mid-level turning is noted about 90 n mi to the east, which
would more closely follow persistence from previous forecasts.
Either way, Franklin is not well organized, and for now the initial
position is held closer to the convection in case a new center
re-forms in that area.  In fact, a dropsonde recently released by
the NOAA crew near the convection measured a surface pressure
of 1003 mb with winds of 32 kt, giving additional credence that a
new center could be forming.  The crew also reported that the SFMR
winds were running too high, and the highest 850-mb flight-level
wind was 41 kt, suggesting that Franklin's initial intensity is
probably down to about 35 kt.
 
The smoothed 12-hour motion remains northwestward (320 degrees) at
6 kt.  The track model guidance continues to insist that Franklin
will move slowly northward and then northeastward during the next 3
days or so, toward broad troughing located over the western
Atlantic.  This track should take Franklin northward across
Hispaniola during the next 12-36 hours, with the system then
turning northeastward over the western Atlantic.  By days 4 and 5,
a shortwave trough is expected to amplify near the northeastern
U.S. while a stronger mid-level ridge develops over the central
Atlantic, likely causing Franklin to turn back to the north by the
end of the forecast period.  Despite the possibility of center
re-formations, which could cause Franklin's track to jump around,
the model guidance is in good agreement on this general forecast
scenario, even if all the details are not yet ironed out.
 
The new intensity forecast probably has the biggest change from the
previous advisory, at least in the short term.  Little change in
strength is expected during the next 48 hours or so due to
Franklin's current disheveled state and its expected crossing of the
high terrain of Hispaniola on Wednesday.  Once Franklin moves over
the western Atlantic waters, a more diffluent upper-level
environment could foster some intensification, and the NHC forecast
continues to show the system becoming a hurricane by the end of the
5-day forecast period.  This forecast remains close to the HCCA and
IVCN consensus aids.
 
 
KEY MESSAGES:
 
1. Heavy rainfall from Franklin is expected across portions of
Hispaniola and Puerto Rico into Thursday. The heavy rainfall may
produce areas of flash and urban flooding as well as river rises and
mudslides. Across Hispaniola, significant and potentially
life-threatening flash flooding is possible Tuesday into Wednesday.
 
2. Franklin is expected to bring tropical storm conditions to
portions of the Dominican Republic and Haiti, where Tropical Storm
Warnings are in effect, beginning later tonight and continuing
through Wednesday.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/2100Z 15.8N  71.4W   35 KT  40 MPH
 12H  23/0600Z 17.0N  71.3W   40 KT  45 MPH
 24H  23/1800Z 19.1N  70.9W   35 KT  40 MPH...OVER HISPANIOLA
 36H  24/0600Z 20.9N  70.3W   35 KT  40 MPH...OVER WATER
 48H  24/1800Z 22.0N  69.3W   40 KT  45 MPH
 60H  25/0600Z 22.5N  68.2W   45 KT  50 MPH
 72H  25/1800Z 22.9N  67.3W   50 KT  60 MPH
 96H  26/1800Z 24.3N  66.7W   60 KT  70 MPH
120H  27/1800Z 27.6N  67.7W   75 KT  85 MPH
 
$$
Forecaster Berg
 

000
FONT13 KNHC 222044
PWSAT3
                                                                    
TROPICAL STORM FRANKLIN WIND SPEED PROBABILITIES NUMBER   9         
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL082023              
2100 UTC TUE AUG 22 2023                                            
                                                                    
AT 2100Z THE CENTER OF TROPICAL STORM FRANKLIN WAS LOCATED NEAR     
LATITUDE 15.8 NORTH...LONGITUDE 71.4 WEST WITH MAXIMUM SUSTAINED    
WINDS NEAR 35 KTS...40 MPH...65 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 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       18Z TUE 06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT
PERIODS         TO      TO      TO      TO      TO      TO      TO  
             06Z WED 18Z WED 06Z THU 18Z THU 18Z FRI 18Z SAT 18Z SUN
                                                                    
FORECAST HOUR    (12)   (24)    (36)    (48)    (72)    (96)   (120)
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 
LOCATION       KT                                                   
                                                                    
BERMUDA        34  X   X( X)   X( X)   X( X)   X( X)   1( 1)   6( 7)
 
MAYAGUANA      34  X   X( X)   X( X)   1( 1)   1( 2)   1( 3)   2( 5)
 
GRAND TURK     34  X   1( 1)   8( 9)   5(14)   3(17)   1(18)   1(19)
GRAND TURK     50  X   X( X)   1( 1)   1( 2)   X( 2)   1( 3)   X( 3)
 
PORT-AU-PRINCE 34  1   2( 3)   X( 3)   1( 4)   X( 4)   1( 5)   X( 5)
 
CAPE BEATA     34 45   8(53)   X(53)   X(53)   X(53)   X(53)   X(53)
CAPE BEATA     50  2   1( 3)   X( 3)   X( 3)   X( 3)   X( 3)   X( 3)
 
PUERTO PLATA   34  1  23(24)  13(37)   1(38)   1(39)   1(40)   X(40)
PUERTO PLATA   50  X   1( 1)   2( 3)   1( 4)   X( 4)   X( 4)   X( 4)
 
SANTO DOMINGO  34  7  21(28)   1(29)   X(29)   1(30)   1(31)   X(31)
 
PONCE PR       34  X   1( 1)   X( 1)   1( 2)   2( 4)   2( 6)   X( 6)
 
AGUADILLA PR   34  1   X( 1)   1( 2)   1( 3)   2( 5)   2( 7)   1( 8)
 
VIEQUES PR     34  X   X( X)   X( X)   1( 1)   1( 2)   2( 4)   1( 5)
 
SAINT THOMAS   34  X   X( X)   X( X)   X( X)   2( 2)   2( 4)   1( 5)
 
SAINT JOHN     34  X   X( X)   X( X)   X( X)   2( 2)   2( 4)   1( 5)
 
SAINT CROIX    34  X   X( X)   X( X)   X( X)   1( 1)   1( 2)   1( 3)
 
$$                                                                  
FORECASTER BERG                                         

000
WTNT23 KNHC 222043
TCMAT3
 
TROPICAL STORM FRANKLIN FORECAST/ADVISORY NUMBER   9
NWS NATIONAL HURRICANE CENTER MIAMI FL       AL082023
2100 UTC TUE AUG 22 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 15.8N  71.4W AT 22/2100Z
POSITION ACCURATE WITHIN  60 NM
 
PRESENT MOVEMENT TOWARD THE NORTHWEST OR 320 DEGREES AT   6 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE 1002 MB
MAX SUSTAINED WINDS  35 KT WITH GUSTS TO  45 KT.
34 KT....... 90NE  90SE   0SW   0NW.
12 FT SEAS.. 75NE  45SE  30SW  60NW.
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 15.8N  71.4W AT 22/2100Z
AT 22/1800Z CENTER WAS LOCATED NEAR 15.4N  71.4W
 
FORECAST VALID 23/0600Z 17.0N  71.3W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT... 70NE  90SE  10SW  10NW.
 
FORECAST VALID 23/1800Z 19.1N  70.9W...OVER HISPANIOLA
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 50NE  70SE   0SW  10NW.
 
FORECAST VALID 24/0600Z 20.9N  70.3W...OVER WATER
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 50NE  50SE  10SW  20NW.
 
FORECAST VALID 24/1800Z 22.0N  69.3W
MAX WIND  40 KT...GUSTS  50 KT.
34 KT... 50NE  50SE  20SW  30NW.
 
FORECAST VALID 25/0600Z 22.5N  68.2W
MAX WIND  45 KT...GUSTS  55 KT.
34 KT... 60NE  70SE  30SW  30NW.
 
FORECAST VALID 25/1800Z 22.9N  67.3W
MAX WIND  50 KT...GUSTS  60 KT.
50 KT... 20NE  20SE   0SW  20NW.
34 KT... 70NE  80SE  30SW  50NW.
 
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 26/1800Z 24.3N  66.7W
MAX WIND  60 KT...GUSTS  75 KT.
 
OUTLOOK VALID 27/1800Z 27.6N  67.7W
MAX WIND  75 KT...GUSTS  90 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 15.8N  71.4W
 
INTERMEDIATE PUBLIC ADVISORY...WTNT33 KNHC/MIATCPAT3...AT 23/0000Z
 
NEXT ADVISORY AT 23/0300Z
 
$$
FORECASTER BERG
 
 

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Tue Aug 22 2023

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

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Franklin, located over the east-central Caribbean Sea, on
Tropical Storm Harold, located inland over south Texas, and has
issued the final advisory on Post-Tropical Cyclone Gert, located a
few hundred miles east-southeast of the northern Leeward Islands.

Eastern Tropical Atlantic (AL92):
Disorganized showers and thunderstorms located a few hundred miles
west of the Cabo Verde Islands are associated with a tropical wave.
Environmental conditions now appear only marginally conducive for
gradual development of this system, but a tropical depression could
still form later this week or over the weekend while it moves
west-northwestward to northwestward across the eastern and central
Atlantic.
* Formation chance through 48 hours…low…10 percent.
* Formation chance through 7 days…medium…40 percent.

Central Tropical Atlantic:
The remnants of former Tropical Storm Emily are located over the
central tropical Atlantic several hundred miles east-northeast of
the Leeward Islands. Although development is unlikely in the next
day or so due to unfavorable environmental conditions, some
development is possible by Friday or Saturday when the system moves
northward over the subtropical central Atlantic. The system should
move north of the Gulf Stream on Sunday where further development is
not expected.
* Formation chance through 48 hours…low…10 percent.
* Formation chance through 7 days…low…30 percent.

$$
Forecaster Papin/R. Zelinsky

 
 000
 NOUS42 KNHC 221513
 REPRPD
 WEATHER RECONNAISSANCE FLIGHTS
 CARCAH, NATIONAL HURRICANE CENTER, MIAMI, FL.
 1115 AM EDT TUE 22 AUGUST 2023
 SUBJECT: TROPICAL CYCLONE PLAN OF THE DAY (TCPOD)
          VALID 23/1100Z TO 24/1100Z AUGUST 2023
          TCPOD NUMBER.....23-084 CORRECTION
 
 I.  ATLANTIC REQUIREMENTS
     1. TROPICAL STORM FRANKLIN
        FLIGHT ONE - NOAA 43          FLIGHT TWO - TEAL 74
        A. 23/1800Z                   A. 23/2330Z,24/0530Z
        B. NOAA3 0508A FRANKLIN       B. AFXXX 0608A FRANKLIN
        C. 23/1400Z                   C. 23/2200Z
        D. 19.8N 70.5W                D. 20.4N 70.2W
        E. 23/1500Z TO 23/2000Z       E. 23/2300Z TO 24/0530Z
        F. SFC TO 10,000 FT           F. SFC TO 10,000 FT
        G. TAIL DOPPLER RADAR         G. FIX
 
        FLIGHT THREE - TEAL 75 (CORRECTED)
        A. 24/1130Z,1730Z
        B. AFXXX 0708A FRANKLIN
        C. 24/1000Z
        D. 22.0N 69.3W
        E. 24/1100Z TO 24/1730Z
        F. SFC TO 10,000 FT
        G. FIX
 
     2. OUTLOOK FOR SUCCEEDING DAY:  BEGIN 12-HRLY FIXES AT 25/0000Z.
     3. REMARK: THE NOAA 49 G-IV TAIL DOPPLER RADAR MISSION TASKED IN
        TCPOD 23-083 WAS CANCELED BY NHC AT 22/1330Z.
 
 II. PACIFIC REQUIREMENTS
     1. NEGATIVE RECONNAISSANCE REQUIREMENTS.
     2. OUTLOOK FOR SUCCEEDING DAY.....NEGATIVE.
 
 $$
 SEF
 
 NNNN