Central Pacific Basin Tropical Cyclones

Tropical Depression Hone Forecast Discussion



000
WTPA41 PHFO 301432
TCDCP1

Tropical Depression Hone Discussion Number  33
NWS Central Pacific Hurricane Center Honolulu HI   CP012024
500 AM HST Fri Aug 30 2024

Like last night, convection bloomed across the eastern flank of 
Hone's low level circulation center (LLCC) between 06Z and 12Z. 
This recent convection partially obscured the LLCC initially, but 
has been sheared eastward just enough to make this feature 
discernible in satellite imagery. Subjective Dvorak satellite 
current intensity estimates were 2.0/30 kt from PHFO and JTWC, and 
1.5/25 kt from SAB. Unfortunately, the ASCAT pass missed Hone 
entirely. The 1110Z objective Dvorak estimate from UW/CIMSS of 32 kt 
remains close to the subjective estimates, and the intensity is set 
at 30 kt for this advisory, maintaining Hone's status as a tropical 
depression.

Hone began a slight turn to the north last evening and continues to 
make this turn with the 12Z cycle. The initial motion of 290 
degrees at 7 kt is in line with the previous forecast track and 
little change was introduced to the current forecast track through 
24 hours. As before, forecast track philosophy revolves around 
likely interaction of the LLCC with an upper low north of Midway 
Atoll. This upper low is forecast to dig southward over the next few 
days and Hone is expected to be pulled northwestward toward it. 
After Hone's LLCC and the upper low become aligned, the tropical 
cyclone is expected to resume a west-northwest motion over the 
western Pacific. The track guidance envelope through 72 hours 
remains rather tight, but has shifted to the right between 24 and 72 
hours, possibly predicting a stronger interaction with the upper 
low.The forecast track for this cycle has been adjusted a bit to 
the right of the previous one from 24 to 72 hours, with little 
change introduced outside of this window. Combined with the current 
motion, this results in a forecast track which depicts a steeper 
climb northward in the mid term.

Hone needs to maintain a shroud of organized deep convection for 
reintensification, and the recent nocturnal bloom was certainly a 
good start. If Hone manages to survive the 45 kt of westerly shear 
it is seeing now, there may be an opportunity for 
reintensification. However, in spite of a bit of a boost from last 
cycle, intensity models remain somewhat bearish on this possibility. 
Only HAFS, representing the high side of the envelope, takes Hone 
back to hurricane/typhoon strength. HWRF depicts Hone as a minimal 
tropical storm through 72 hours before granting a bit of 
strengthening. HCCA gradually strengthens Hone to 50 kt at 72 hours, 
then tries to dissipate it shortly after 120 hours. Global models 
generally try to do the same. In other words, intensity guidance 
varies widely after 48 hours as each model or ensemble copes with 
the uncertainty associated with Hone's interaction with the upper 
low north of Midway Atoll. The current intensity forecast closely 
follows the previous one, which lies within the wide guidance 
spread. Following our track and intensity forecast, Hone should 
cross the International Dateline as a mid-range tropical storm on 
Sunday, Hawaii time.

FORECAST POSITIONS AND MAX WINDS

INIT  30/1500Z 21.8N 174.7W   30 KT  35 MPH
 12H  31/0000Z 22.4N 175.7W   30 KT  35 MPH
 24H  31/1200Z 23.7N 176.4W   35 KT  40 MPH
 36H  01/0000Z 24.8N 177.3W   40 KT  45 MPH
 48H  01/1200Z 25.8N 178.6W   40 KT  45 MPH
 60H  02/0000Z 26.6N 179.7E   45 KT  50 MPH
 72H  02/1200Z 27.1N 177.8E   45 KT  50 MPH
 96H  03/1200Z 28.7N 174.2E   50 KT  60 MPH
120H  04/1200Z 31.3N 171.1E   50 KT  60 MPH

$$
Forecaster Powell



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