Central Pacific Basin Tropical Cyclones

Hurricane Dora Forecast Discussion

WTPA42 PHFO 082055

Hurricane Dora Discussion Number  34
NWS Central Pacific Hurricane Center Honolulu HI   EP052023
1100 AM HST Tue Aug 08 2023

Dora remains a powerful but small hurricane this morning, with a 
persistent and relatively symmetric ring of deep convection 
surrounding an eye that has recently become somewhat cloud-filled. 
With a lack of discrete rain bands, a well-defined eye, and a 
resistance to intensity change, Dora has displayed characteristics 
of an annular hurricane for at least the last day or so, despite an 
AHI (Annular Hurricane Index) score of zero this morning. 
Regardless, utilizing subjective Dvorak current intensity estimates 
of 6.0/115 kt, a 1618Z RCM-2 SAR pass, and 1431Z and 1436Z 
microwave intensity estimates from UW-CIMSS' D-MINT, the initial 
intensity is estimated to be 115 kt. 

The initial motion vector for this advisory is 270/19 kt, as Dora 
continues on its rapid westward track across the basin. A deep-layer 
ridge moving westward in tandem with Dora had been supporting this 
motion, and will generally continue to do so for the next day or 
two. Despite the recent (somewhat unusual) south of west motion, 
the forecast track anticipates that Dora will gradually gain 
latitude as it reaches the southwestern periphery of the ridge. The 
updated track forecast is nudged slightly northward from the 
previous forecast, closer to the well-performing HAFS-A and TVCE 
guidance. On the forecast track, Dora will pass well south of 
Johnston Island Wednesday night, and into the western Pacific basin 
on Friday.

Environmental conditions along the forecast track remain conducive 
for maintaining a strong tropical cyclone over the next couple of 
days, with relatively low vertical wind shear and sufficiently high 
SSTs/OHC. Little change in intensity is indicated in the updated 
forecast until the later forecast periods, when increasing 
southwesterly vertical wind shear may lead to a fairly rapid demise 
of the small cyclone's core. The updated intensity forecast lies 
close to the IVCN consensus, with LGEM guidance influencing the 
forecast in the later periods. 


INIT  08/2100Z 11.5N 158.1W  115 KT 130 MPH
 12H  09/0600Z 11.6N 161.0W  110 KT 125 MPH
 24H  09/1800Z 12.0N 164.8W  105 KT 120 MPH
 36H  10/0600Z 12.5N 168.5W  100 KT 115 MPH
 48H  10/1800Z 13.3N 172.0W  100 KT 115 MPH
 60H  11/0600Z 14.3N 175.4W   95 KT 110 MPH
 72H  11/1800Z 15.5N 178.5W   90 KT 105 MPH
 96H  12/1800Z 17.6N 175.6E   65 KT  75 MPH
120H  13/1800Z 19.0N 170.0E   45 KT  50 MPH

Forecaster Birchard

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