197 
WTPA42 PHFO 151453
TCDCP2
 
Tropical Storm Lala Discussion Number  13
NWS Central Pacific Hurricane Center Honolulu HI   CP012026
Issued by NWS National Hurricane Center Miami FL
500 AM HST Sat Aug 15 2026

A ragged eye-like feature has formed in radar imagery from the
South Point, Hawaii, radar site, even though Lala's satellite
presentation has not improved much since the previous advisory.
Radar velocities are as high as 55-60 kt between 10,000 and 15,000
ft in deep convection to the northeast of the center. Along with
satellite estimates, these data support holding Lala's intensity at
55 kt.
 
Lala's current motion remains west-northwestward, or 285/11 kt, but
that is likely to change later today as the circulation begins to
interact with terrain of the Big Island. Dynamical model fields
suggest that the center may get pulled northwestward into or near
the Big Island later this afternoon while at the same time a
leeside trough or broad low forms west of the island. This may
cause a discontinuous track that is reflected in the official
forecast points or track forecast cone. After the cyclone
reconstitutes itself west of the Big Island, it is likely to turn
toward the west on Sunday and continue on that path for several
days due to high pressure north of the Hawaiian Islands. A
shortwave trough moving across the northern Pacific around the
middle of next week may weaken the ridge enough to allow Lala to
turn toward the west-northwest and then northwest, potentially
approaching western portions of the Northwestern Hawaiian
Islands.
 
Lala has about 12 hours left for some strengthening before the
center reaches the Big Island, and the NHC forecast continues to
show the storm becoming a hurricane near the southern coast of the
Big Island. Even if the storm only manages to strengthen slightly,
there is no practical difference between a 60-kt tropical storm and
a 65-kt hurricane, especially since hurricane-force gusts are
expected on the Big Island regardless. Weakening is expected after
the circulation interacts with the Big Island, and it will likely
take a few days for the storm to re-organize. Environmental
conditions appear conducive to support intensification in 3-5 days.
The intensity guidance has not changed much of this cycle, and the
new NHC forecast is very similar to the previous one.
 
Lala's center is sufficiently well defined in radar imagery that we
plan to start hourly updates at 6 AM HST (1600 UTC) via the
Tropical Cyclone Update product (HFOTCUCP2). These hourly updates
will continue as long as the center remains well defined in radar
imagery.
 
 
Key Messages:
 
1. Damaging hurricane-force winds are expected on the Big Island of
Hawaii later today, with the strongest wind gusts expected in areas
of higher terrain. Tropical-storm-force winds are already beginning
on the Big Island, and preparations should now be complete.
Tropical-storm-force wind gusts are also beginning across portions
of the smaller islands and should continue through Sunday.
 
2. Heavy rainfall will continue to increase over the Big Island this
morning and then spread westward across the remainder of the island
chain over the weekend. This rainfall will produce life-threatening
flooding and mudslides, especially in areas of steep terrain.
 
3. Large and dangerous waves are expected across portions of the
Hawaiian Islands this weekend. Surf is already building along
east-facing shores and will increase along exposed southern shores
as Lala passes through the region. This heavy surf may cause
localized coastal flooding and significant beach erosion.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  15/1500Z 17.8N 154.6W   55 KT  65 MPH
 12H  16/0000Z 18.7N 155.5W   65 KT  75 MPH
 24H  16/1200Z 19.9N 158.1W   55 KT  65 MPH
 36H  17/0000Z 20.3N 160.9W   50 KT  60 MPH
 48H  17/1200Z 20.5N 163.2W   50 KT  60 MPH
 60H  18/0000Z 20.6N 165.4W   55 KT  65 MPH
 72H  18/1200Z 20.7N 167.3W   60 KT  70 MPH
 96H  19/1200Z 21.6N 170.5W   65 KT  75 MPH
120H  20/1200Z 23.5N 172.7W   70 KT  80 MPH
 
$$
Forecaster Berg