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WTPA42 PHFO 190247
Hurricane Lane Discussion Number 17
NWS Central Pacific Hurricane Center Honolulu HI EP142018
500 PM HST Sat Aug 18 2018
Lane's satellite presentation has degraded a bit over the past few
hours, with the eye clouding over and cooling. The central
convective ring has become a bit asymmetric, becoming elongated
east-to west roughly along the axis of 15 to 18 kt vertical shear.
Outflow seems more favorable now to the east-northeast than 6 to 12
hours ago. Nevertheless, Lane remains a powerful hurricane, with
objective Dvorak Current Intensity (CI) numbers between 6.0/115 kt
(JTWC/SAB) and 6.5/127 kt (PHFO). ADT from UW-CIMSS is weaker at
5.0/105 kt. The initial intensity is set at 115 kt for this
advisory, based on a mix of these estimates.
Lane continues moving toward the west-northwest at about 14 kt,
representing a slight increase in forward speed. This system
should continue on this track through 24 hours, driven by a large
subtropical ridge to its north. As the ridge builds westward, Lane
should shift to a more westerly track from 24 through 72 hours. A
shift back toward the west-northwest should occur from 96 through
120 hours as Lane approaches the western portion of the ridge.
Track guidance remains rather tight, depicting a gradual decrease
in forward speed through the forecast period. The first few
forecast points were pushed forward slightly to account for the
small bump in initial forward speed, but the overall forecast track
closely resembles the previous one, neatly following TVCE consensus.
The intensity forecast roughly follows IVCN consensus guidance,
depicting a gradual weakening through 120 hours. SSTs will remain
in the 27 to 28 degree C range, but with 10 to 15 kt of vertical
shear expected through the forecast period, a forecast for gradual
weakening seems sound.
Lane is forecast to pass south of the main Hawaiian Islands
Wednesday and Thursday, potentially causing local impacts as it
tracks west northwestward. Interests in those islands should watch
the progress of Lane closely, since day 4 and 5 forecast track
errors can be large.
FORECAST POSITIONS AND MAX WINDS
INIT 19/0300Z 12.8N 141.0W 115 KT 130 MPH
12H 19/1200Z 13.2N 143.0W 105 KT 120 MPH
24H 20/0000Z 13.5N 145.2W 100 KT 115 MPH
36H 20/1200Z 13.7N 147.1W 95 KT 110 MPH
48H 21/0000Z 13.9N 148.9W 90 KT 105 MPH
72H 22/0000Z 14.2N 152.2W 80 KT 90 MPH
96H 23/0000Z 15.0N 155.7W 65 KT 75 MPH
120H 24/0000Z 16.2N 159.2W 55 KT 65 MPH