Central Pacific Basin Tropical Cyclones

Hurricane Dora Forecast Discussion



000
WTPA42 PHFO 091436
TCDCP2

Hurricane Dora Discussion Number  37
NWS Central Pacific Hurricane Center Honolulu HI   EP052023
500 AM HST Wed Aug 09 2023

Dora is on track to pass far south of Johnston Island later today, 
with large surf lasting through Thursday. Compact and powerful Dora 
continues to have a well-defined eye with a ring of persistant and 
symmetrical convection overnight. Satellite animation shows Dora has 
started to move slightly north of west over the last few hours. 
Subjective Dvorak estimates of 6.0 from PHFO and 5.5 from both SAB 
and JTWC, and the CIMSS objective estimates between 104 and 112 kt, 
show that Dora has changed little overnight. More recent satellite 
images show the system developing colder cloud tops suggesting that 
Dora has gone through some minor fluctuations and remains around 
115 kt, thus have held the intensity.

The initial motion with this advisory is 275/19 kt. Model guidance 
remains closely clustered through the remaining time Dora will be 
exploring the central Pacific. Dora continues to move to the west, 
along the southern edge of a strong ridge to the north. The westward 
track will become west-northwestward later today as it moves along 
the southwestern edge of the ridge, and turn to the northwest 
Thursday as it approaches the date line. There remains more 
variability in the track and speed as the tropical cyclone enters 
the western Pacific basin on Friday. The forecast track remains 
closely aligned with the previous advisory, and largely follows 
the TVCN model consensus.

The environmental conditions surrounding, and immediately ahead of 
Dora continue to be favorable, with the system moving into slightly 
warmer waters today with neglible shear. Combined with little change 
in intensity over the last 24 hours, and the 06Z ECMWF SHIPS having 
indicated a steady state through 11/06Z, have held the intensity 
higher than the previous advisory for the first 24 hours. 
Southwesterly deep layer shear will increase around hour 48, which 
despite moving over even warmer waters at the time, is likely to 
contribute to a weakening trend. The shear is expected to increase 
as the system moves across the date line on Friday. The 
forecast intensity keeps it a little higher than most of the models 
in the short term, and leans towards the LGEM guidance for the 
later periods.


FORECAST POSITIONS AND MAX WINDS

INIT  09/1500Z 11.4N 164.0W  115 KT 130 MPH
 12H  10/0000Z 11.8N 166.9W  115 KT 130 MPH
 24H  10/1200Z 12.6N 170.6W  110 KT 125 MPH
 36H  11/0000Z 13.4N 174.0W  110 KT 125 MPH
 48H  11/1200Z 14.5N 177.2W  105 KT 120 MPH
 60H  12/0000Z 15.6N 180.0E  100 KT 115 MPH
 72H  12/1200Z 16.5N 177.2E   90 KT 105 MPH
 96H  13/1200Z 17.7N 172.3E   65 KT  75 MPH
120H  14/1200Z 18.9N 167.9E   50 KT  60 MPH

$$
Forecaster M Ballard/Jelsema



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