Central Pacific Basin Tropical Cyclones

Hurricane Dora Forecast Discussion

WTPA42 PHFO 070833

Hurricane Dora Discussion Number  28
NWS Central Pacific Hurricane Center Honolulu HI   EP052023
1100 PM HST Sun Aug 06 2023

The satellite presentation of Dora remains impressive this evening 
with a very warm 10 nautical mile wide eye surrounded by a very cold 
dense overcast. The latest subjective Dvorak current intensity 
estimates from PHFO, SAB, and JTWC came in at 6.0 (115 kt), 6.5 (127 
kt), 6.5 (127 kt) respectively, while the objective Dvorak ADT and 
AiDT estimates from UW-CIMSS were both 6.0 (115 kt). Using a blend 
of these data, the initial intensity is set at 120 kt.

Dora is moving slightly south of due west at 20 kt. This general 
motion is expected to continue during the next several days as a 
deep layer ridge builds to the north of the Hawaiian Islands. A 
turn to the northwest is forecast beyond day 3 as the tropical 
cyclone rounds the southwestern periphery of the deep layer 
subtropical ridge to the north of Hawaii. On this forecast track, 
Dora is expected to move into the western Pacific basin late this 
week. The forecast track has changed little from the previous 
advisory and is roughly a blend of the HCCA and TVCN consensus 
guidance and deterministic GFS and ECMWF guidance.

The environmental conditions along the forecast track of Dora during 
the next several days are generally conducive for maintenance of a 
very intense tropical cyclone, with the exception of the mid-level 
dry air surrounding the system. Vertical wind shear will remain low 
during the next 4 days, while sea surface temperatures remain around 
27C. Beyond day 4 the SSTs increase into the 28/29C range, but 
vertical wind shear is forecast to rise substantially. Given the 
current annular appearance of Dora, the intensity forecast calls 
for a very slow and steady decrease through the forecast period, 
with the tropical cyclone being influenced primarily by the dry 
mid-level environment surrounding the system. This forecast is 
essentially a blend of the statistical and dynamical intensity 
guidance and very close to the previous intensity forecast through 
day 3, and slightly higher at days 4 and 5.


INIT  07/0900Z 12.5N 146.3W  120 KT 140 MPH
 12H  07/1800Z 12.4N 149.1W  115 KT 130 MPH
 24H  08/0600Z 12.3N 152.9W  110 KT 125 MPH
 36H  08/1800Z 12.2N 156.8W  105 KT 120 MPH
 48H  09/0600Z 12.3N 160.7W   95 KT 110 MPH
 60H  09/1800Z 12.5N 164.4W   90 KT 105 MPH
 72H  10/0600Z 12.9N 168.0W   90 KT 105 MPH
 96H  11/0600Z 14.5N 175.5W   80 KT  90 MPH
120H  12/0600Z 16.5N 178.5E   70 KT  80 MPH

Forecaster Jelsema

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