Central Pacific Basin Tropical Cyclones

Tropical Storm Hone Forecast Discussion



000
WTPA41 PHFO 010246
TCDCP1

Tropical Storm Hone Discussion Number  39
NWS Central Pacific Hurricane Center Honolulu HI   CP012024
500 PM HST Sat Aug 31 2024

Earlier this afternoon, the increasingly ragged low-level 
circulation center (LLCC) of Hone tucked itself underneath a burst 
of deep convection, but as the convection began to dissipate, it 
caused even more disruption to the once again exposed LLCC. GOES-
West derived total precipitable water imagery reveals a nose of 
dry air is working cyclonically around the southern portion of an 
upper low about 220 nm south of Midway Atoll. This dry air has 
managed to overspread what's left of Hone's LLCC. Current intensity 
estimates remain 2.0 from PHFO and JTWC, and 2.5 from SAB. 
Objective estimates were slightly higher, and seemed to agree well 
with the uncontaminated ASCAT-B winds from the 2149 UTC pass. Thus, 
the initial intensity is maintained at 35 kt for this advisory. 

The initial motion is 340/9, as Hone continues to work its way 
toward the low aloft. The track guidance is in good agreement that 
Hone's more recent northward motion will become more west-northwest 
again over the next 24 hours as the two features merge. This should 
be followed by significant slowing in the 24 to 36 hour timeframe. 
An erratic, slow motion between 36 and 48 hours should lead to a 
gradually increasing northward motion near the International Date 
Line by 48 hours as the now vertically-aligned Hone starts to move 
toward a mid-level col. The track guidance beyond 48 hours 
continues to trend slower with Hone as the models now show a deep 
layer anticyclone at the surface and aloft building north of the 
system. The forecast once again has been similarly adjusted toward 
the guidance consensus at the longer time ranges. 

The intensity forecast remains rather challenging, and the guidance 
continues to trend gradually weaker with time. Although Hone is 
finally entering a weak shear environment with sea surface 
temperatures of 28C or so through the first 48 hours, increasing 
dry air entrainment is now expected to allow for only modest 
intensification. The latest forecast has been adjusted slightly 
lower once again to follow this idea, but near the high 
end of the envelope of the reliable guidance.

Due to the greater-than-normal uncertainties in the track, size, 
and intensity of Hone as it continues to interact with the low 
aloft, we are maintaining Tropical Storm Watches for Kure, 
Midway Atoll, and Pearl and Hermes Atolls.


FORECAST POSITIONS AND MAX WINDS

INIT  01/0300Z 23.9N 176.7W   35 KT  40 MPH
 12H  01/1200Z 25.1N 177.5W   35 KT  40 MPH
 24H  02/0000Z 26.1N 179.2W   40 KT  45 MPH
 36H  02/1200Z 26.5N 179.9E   40 KT  45 MPH
 48H  03/0000Z 27.5N 179.9E   45 KT  50 MPH
 60H  03/1200Z 29.0N 180.0E   45 KT  50 MPH
 72H  04/0000Z 30.4N 179.6E   40 KT  45 MPH
 96H  05/0000Z 32.2N 178.1E   35 KT  40 MPH
120H  06/0000Z 33.9N 176.8E   30 KT  35 MPH

$$
Forecaster R Ballard



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