Central Pacific Basin Tropical Cyclones

Hurricane Dora Forecast Discussion

WTPA42 PHFO 090239

Hurricane Dora Discussion Number  35
NWS Central Pacific Hurricane Center Honolulu HI   EP052023
500 PM HST Tue Aug 08 2023

Dora remains a powerful but small hurricane this afternoon, with a
persistent and relatively symmetric ring of deep convection
surrounding the eye. 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. At fix time, 
subjective Dvorak intensity estimate of 5.5 from both PHFO and SAB, 
while objective Dvorak ADT shows a value of 5.8. Cold cloud tops 
have wrapped around the convection this afternoon and little overall 
change in appearance over the last 24 hours supports keeping the 
intensity at 115 kt.

The initial motion vector for this advisory is 265/20 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. 
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 southward from the
previous forecast, closer model consensus. 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  09/0300Z 11.4N 160.1W  115 KT 130 MPH
 12H  09/1200Z 11.6N 163.1W  110 KT 125 MPH
 24H  10/0000Z 12.0N 166.9W  105 KT 120 MPH
 36H  10/1200Z 12.7N 170.5W  100 KT 115 MPH
 48H  11/0000Z 13.5N 173.9W   95 KT 110 MPH
 60H  11/1200Z 14.6N 177.1W   95 KT 110 MPH
 72H  12/0000Z 15.8N 179.9E   90 KT 105 MPH
 96H  13/0000Z 17.5N 174.0E   65 KT  75 MPH
120H  14/0000Z 18.9N 168.6E   45 KT  50 MPH

Forecaster Foster/Birchard

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