Post-Tropical Cyclone Linda Discussion Number 42
NWS Central Pacific Hurricane Center Honolulu HI EP122021
500 AM HST Fri Aug 20 2021
Linda's time as a tropical cyclone has come to an end. Infrared and
VIIRS day-night satellite imagery depict an elongating low cloud
swirl, and deep convection has been absent over the center for
nearly 24 hours, thus Linda is deemed to be post-tropical. The
initial intensity estimate of 35 kt for this advisory remains
heavily influenced by a recent scatterometer pass that indicated
winds to 40 kt north of the center.
The initial motion estimate is 280/15 kt, with Linda being steered
by a persistent low- to mid-level ridge to the north. Tightly-
clustered track guidance indicates that the ridge will continue to
drive the post-tropical remains of Linda toward the west, with a
slight reduction in forward speed tonight and Saturday. The guidance
has trended southward over the last couple of days, and the official
forecast indicates that remnants of Linda will impact portions of
the main Hawaiian Islands Sunday and Monday, in line with the
corrected consensus guidance HCCA, and the GEFS mean.
Compared to the recent rapid weakening, a relatively slow rate of
decay of the wind field is expected over the next couple of days.
As the system gradually spins down, gale force winds north of the
center will be slow to diminish, due to the gradient between the
high to the north and the remnant low. Some sporadic deep convection
may also occur, but the combined effects of dry air in the mid- and
upper-levels and increasing vertical wind shear will prevent
regeneration into a tropical cyclone, and lead to system dissipation
by day 4. This is supported by the reliable global models, as well
as the intensity consensus IVCN.
This is the last advisory issued by the Central Pacific Hurricane
Center on Linda. Future information on this system can be found in
forecasts issued by the National Weather Service in Honolulu, on
the web at http://weather.gov/hfo.