Tropical Cyclone Discussion

313
WTPA42 PHFO 131439
TCDCP2
 
Tropical Storm Lala Discussion Number   5
NWS Central Pacific Hurricane Center Honolulu HI   CP012026
Issued by NWS National Hurricane Center Miami FL
500 AM HST Thu Aug 13 2026

Over the past several hours, deep convection has been increasing 
near the center and in bands on the north side of the system.  In 
addition, the circulation appears less elongated and more 
consolidated.  Based on the improvement in its appearance, the 
system now meets the criteria of a tropical storm.  The initial 
intensity of Lala is estimated to be 35 kt, which is near the middle 
of the latest satellite intensity estimates.  An Air Force 
reconnaissance aircraft is scheduled to investigate Lala later this 
morning, and that data will be quite helpful in better assessing the 
storm's intensity and structure.
 
Lala is moving generally westward at about 9 kt.  The track forecast
philosophy appears fairly straightforward.  A large mid-level high
pressure system located to the north of the Hawaiian Islands should
keep Lala on a westward to west-northwestward track, taking the core
of the system near or just south of the Big Island by early
Saturday.  Lala will very likely pass south of the smaller islands
during the remainder of the weekend.  The guidance has trended a bit
to the south this cycle, and the NHC track forecast has been nudged
in that direction.  It is important to note, that the NHC 48-h track
error is about 50 to 60 miles.
 
The storm is likely to strengthen during the next couple of days as
the environmental conditions are expected to be generally favorable
for the system.  The NHC intensity forecast brings Lala up to 60 kt
around the time it nears the Big Island, but there is some very
skillful guidance, including the Google DeepMind and HCCA that show
it becoming a category 1 hurricane during that time.  An upper-level
low is expected to develop and impart shear, helping intrude dry air
in the circulation when Lala moves to the south of the smaller
islands, and that could cause some weakening this weekend.
However, re-strengthening is forecast early next week when the
system pulls away from the Hawaiian Islands. The NHC intensity
forecast lies near the high end of the guidance in the short term,
but lies near the middle of the guidance envelope thereafter.
 
 
Key Messages:
 
1. Lala is forecast to strengthen and it could be near hurricane 
strength when it approaches the Big Island by early Saturday.  A 
Hurricane Watch has been issued for the island. Winds are expected 
to be the strongest downslope of higher terrain, over headlands, and 
through passes.
 
2. Heavy rainfall associated with Tropical Storm Lala will begin to 
impact the Big Island Friday, spreading westward across the island 
chain during the weekend.  This rainfall may produce 
life-threatening flooding and mudslides, especially in areas of 
steep terrain.

3. Large and dangerous waves, especially on the Big Island, are 
expected this weekend, with the greatest impacts along the southern 
shores. This prolonged period of heavy surf may cause localized 
coastal flooding and significant beach erosion.
 
4. Interests in the smaller islands should monitor the progress of 
Lala, and Tropical Storm Watches could be required later today or 
Friday.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  13/1500Z 15.2N 145.5W   35 KT  40 MPH
 12H  14/0000Z 15.9N 146.9W   40 KT  45 MPH
 24H  14/1200Z 16.6N 149.2W   45 KT  50 MPH
 36H  15/0000Z 17.4N 151.7W   50 KT  60 MPH
 48H  15/1200Z 18.0N 154.1W   60 KT  70 MPH
 60H  16/0000Z 18.7N 156.3W   60 KT  70 MPH
 72H  16/1200Z 19.6N 159.0W   55 KT  65 MPH
 96H  17/1200Z 21.0N 164.3W   60 KT  70 MPH
120H  18/1200Z 22.6N 169.5W   70 KT  80 MPH