Central Pacific Basin Tropical Cyclones

Hurricane Dora Forecast Discussion

WTPA42 PHFO 080843

Hurricane Dora Discussion Number  32
NWS Central Pacific Hurricane Center Honolulu HI   EP052023
1100 PM HST Mon Aug 07 2023

The satellite presentation of Dora remains impressive this evening, 
with the tropical cyclone continuing to display annular 
characteristics. The 15 nautical mile wide eye remains very warm and 
surrounded by a very cold dense overcast. Microwave imagery from 
earlier this evening showed a well defined eyewall structure in 
place as well. The latest subjective Dvorak current intensity 
estimates from PHFO and SAB were both 6.0 (115 kt), while the 
objective Dvorak ADT and AiDT estimates from UW-CIMSS were 117 kt 
each. As a result, the initial intensity has been held at 115 kt for 
this advisory.

Dora is moving slightly south of due west at 20 kt. This general 
motion is expected to continue during the next couple days as a deep 
layer ridge builds north of the Hawaiian Islands. A turn to the 
west- northwest is forecast beyond day 2 as the tropical cyclone 
rounds the southwestern periphery of the deep layer subtropical 
ridge north of Hawaii. On this forecast track, Dora is expected to 
move into the western Pacific basin late Friday. The official 
forecast track was nudged southward slightly during the next couple 
days due to the recent southward jog that Dora has taken and to 
bring it in better alignment with the latest consensus guidance. 
Beyond 48 hours, the forecast track is virtually identical to the 
previous advisory. 

The environmental conditions along the forecast track of Dora appear 
conducive for maintaining a very intense tropical cyclone during the 
next several days, with the only potential negative factor being the 
surrounding dry mid-level air around the system. Given the current 
annular appearance of Dora, and the fact it has appeared annular for 
several days now, the dry mid-level air surrounding the storm will 
likely have a difficult time being entrained into the system. 
Vertical wind shear will remain low during the next 3 days, before 
increasing slightly by day 4, and more substantially by day 5. 
Meanwhile sea surface temperatures will change little during the 
next 24 to 36 hours, remaining around 27C. Beyond 36 hours, the SSTs 
will gradually increase into the 28/29C range, with ocean heat 
content values rising considerably from day 2 onward. The official 
intensity forecast shows a slow and gradual decrease during the next 
24 hours, with the intensity then held steady through day 3. There 
is the potential that Dora could strengthen again in the 48 through 
72 hour time frame due to the increase in SSTs and OHC. By day 4, 
vertical wind shear should begin to impact the tropical cyclone, 
with a more drastic decline in intensity expected by day 5 as shear 
begins to overwhelm Dora. This forecast is weighted heavily toward 
the intensity consensus guidance, which has been performing much 
better than the dynamical models over the last couple days.


INIT  08/0900Z 11.7N 154.2W  115 KT 130 MPH
 12H  08/1800Z 11.6N 157.2W  110 KT 125 MPH
 24H  09/0600Z 11.6N 161.1W  105 KT 120 MPH
 36H  09/1800Z 11.9N 164.8W  105 KT 120 MPH
 48H  10/0600Z 12.5N 168.5W  105 KT 120 MPH
 60H  10/1800Z 13.3N 172.2W  105 KT 120 MPH
 72H  11/0600Z 14.5N 175.7W  105 KT 120 MPH
 96H  12/0600Z 16.8N 178.4E   90 KT 105 MPH
120H  13/0600Z 18.5N 172.6E   60 KT  70 MPH

Forecaster Jelsema

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