Tropical Cyclone Discussion

561
WTPA42 PHFO 031437
TCDCP2
 
Hurricane Nolo Discussion Number  52
NWS Central Pacific Hurricane Center Honolulu HI   EP152026
Issued by NWS National Hurricane Center Miami FL
500 AM HST Sat Oct 03 2026

Nolo may be taking a short breather during its intensification
phase. The hurricane has a fairly symmetric convective pattern,
with cloud tops as cold as -68 degrees Celsius in the southern
eyewall and an eye temperature of about 14 degrees Celsius. This
pattern yielded subjective Dvorak estimates of T5.0/90 kt from HFO
and JTWC, while objective numbers from UW-CIMSS are as high as
90-95 kt. As a result, Nolo's current intensity is maintained at 95
kt.
 
Nolo is moving faster as expected, and the current motion is now
westward (265 degrees) at 12 kt. Strong ridging to the north is
expected to cause Nolo to accelerate further toward the west,
potentially reaching a forward speed of around 20 kt by day 4. The
track models are very tightly clustered for the next 3 days, and
confidence in that part of the forecast is very high. Nolo is
expected to be west of the International Date Line by hour 36.
There is higher-than-normal spread in the guidance on days 4 and 5,
mainly related to how Nolo might interact with a disturbance
currently near the Marshall Islands (Invest 94W) and a longwave
trough expected to move east of Japan. The NHC forecast favors the
models on the southern end of the guidance envelope, showing a
continued westward track, and is very close to the previous
prediction.
 
Nolo's intensification is likely to resume soon while it moves over
sea surface temperatures around 28 degrees Celsius, and deep-layer
shear becomes almost negligible. A lot of dry air surrounds the
hurricane, with mid-level relative humidity around 40 percent,
but the low shear should minimize how much dry air can
infiltrate Nolo's circulation. Nolo is expected to become a major
hurricane later today and could peak at category 4 intensity in
about 36 hours, if not sooner. There is some model signal for a
faster rate of intensification during the first 24 hours than what
is shown in the official forecast, with the SHIPS Rapid
Intensification Index showing a 40 percent chance of a 20-kt
increase in winds over the next 12 hours. The HAFS-A/B hurricane
models are also slightly higher through 36 hours. Internal dynamics,
such as an eyewall replacement, as well as a slight increase in
shear will likely induce some weakening after 36 hours, but Nolo is
expected to remain a hurricane--or a typhoon west of the Date
Line--through the end of the 5-day forecast period.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  03/1500Z 23.1N 171.2W   95 KT 110 MPH
 12H  04/0000Z 23.2N 173.9W  105 KT 120 MPH
 24H  04/1200Z 23.6N 177.4W  115 KT 130 MPH
 36H  05/0000Z 24.3N 179.3E  120 KT 140 MPH
 48H  05/1200Z 25.1N 176.2E  115 KT 130 MPH
 60H  06/0000Z 25.3N 172.8E  110 KT 125 MPH
 72H  06/1200Z 25.5N 168.8E  100 KT 115 MPH
 96H  07/1200Z 26.2N 160.4E   80 KT  90 MPH
120H  08/1200Z 26.9N 153.8E   70 KT  80 MPH