Advisories

000
WTPA42 PHFO 220842
TCDCP2
 
Hurricane Lala Discussion Number  40
NWS Central Pacific Hurricane Center Honolulu HI   CP012026
Issued by NWS National Hurricane Center Miami FL
1100 PM HST Fri Aug 21 2026
 
Lala's structure has evolved over the past 6-12 hours due to
interaction with an upper-level trough to its west and southwest.
Deep convection has been sheared away from the center due to nearly
30 kt of south-southwesterly shear, and moderate convection now
wraps around the northern and western side of the circulation,
very similar to the structure of an occluded extratropical low.
Dvorak Current Intensity numbers from HFO and JTWC are still 4.5/77
kt, and given that winds can be slow to decrease when a tropical
cyclone positively interacts with an upper-level trough, the
current intensity estimate remains 75 kt. It is estimated that
Lala's wind field has also expanded as a result of the trough
interaction. A pair of ASCAT passes should hit the cyclone soon to
give us a better estimate of Lala's intensity and size.
 
The interaction with the trough has also caused Lala to turn and
temporarily accelerate toward the northwest (325/12 kt). A mid-level
ridge to the northeast should force the cyclone on a northwestward
trajectory for the next 3 days, but the steering is so weak that
Lala is likely to slow down considerably, only moving at 4-5 kt on
Sunday and Monday. A motion toward the north-northwest could occur
by Tuesday and Wednesday as the ridge shifts east of Lala, but
there is model spread regarding the degree and speed of that turn.
The NHC track forecast lies just left of the center of the guidance
envelope, leaning toward the HCCA and GDMI guidance, and is also not
very different from the previous forecast.
 
Deep-layer shear is forecast to fall to 10 kt or less in about 12
hours once Lala becomes embedded within the larger-scale longwave
trough. Since the hurricane is expected to slow down, water
temperatures and atmospheric instability are only expected to
gradually decrease during the next few days, which should allow for
at least moderate convection to continue. The NHC intensity
forecast continues to show gradual weakening, generally close to
the IVCN intensity consensus, and Lala could still be a tropical
cyclone at the end of the 5-day forecast period.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  22/0900Z 30.3N 172.0W   75 KT  85 MPH
 12H  22/1800Z 31.3N 172.7W   70 KT  80 MPH
 24H  23/0600Z 32.2N 173.6W   65 KT  75 MPH
 36H  23/1800Z 33.0N 174.4W   60 KT  70 MPH
 48H  24/0600Z 33.6N 175.0W   55 KT  65 MPH
 60H  24/1800Z 34.3N 175.6W   50 KT  60 MPH
 72H  25/0600Z 35.1N 176.4W   45 KT  50 MPH
 96H  26/0600Z 36.8N 178.1W   45 KT  50 MPH
120H  27/0600Z 38.9N 179.4W   40 KT  45 MPH
 
$$
Forecaster Berg