000
WTPA32 PHFO 230844
TCPCP2
BULLETIN
Tropical Depression Fifteen-E Advisory Number 11
NWS Central Pacific Hurricane Center Honolulu HI EP152026
Issued by NWS National Hurricane Center Miami FL
1100 PM HST Tue Sep 22 2026
...DEPRESSION REDEVELOPS SOUTHEAST OF HAWAIIAN ISLANDS...
...FORECAST TO STRENGTHEN QUICKLY...
SUMMARY OF 1100 PM HST...0900 UTC...INFORMATION
-----------------------------------------------
LOCATION...14.0N 153.7W
ABOUT 405 MI...650 KM SSE OF HILO HAWAII
ABOUT 575 MI...925 KM SSE OF HONOLULU HAWAII
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES
WATCHES AND WARNINGS
--------------------
Interests in the Hawaiian Islands should closely monitor the
progress of this system. A Hurricane or Tropical Storm Watch will
likely be required for a portion of the state on Wednesday.
DISCUSSION AND OUTLOOK
----------------------
At 1100 PM HST (0900 UTC), the center of Tropical Depression
Fifteen-C was located near latitude 14.0 North, longitude 153.7
West. The depression is moving toward the west-northwest near 12 mph
(19 km/h) and this motion with a decrease in forward speed is
expected for the next day or so. A sharp turn to the north or
north-northeast is expected on Thursday, with this motion continuing
through the end of the week. On the forecast track, the depression
is expected to approach the Big Island of Hawaii on Friday, as a
hurricane.
Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Steady strengthening is forecast, and the system is expected to be
a tropical storm later today and a hurricane in a couple of days.
The estimated minimum central pressure is 1006 mb (29.71 inches).
HAZARDS AFFECTING LAND
----------------------
Key messages for Tropical Depression Fifteen-E can be found in the
can be found in the Tropical Cyclone Discussion under AWIPS header
HFOTCPCP2 and WMO header WTPA42 PHFO.
WIND: There is an increasing risk of wind impacts in the Hawaiian
Islands regardless of the exact track of this system.
RAINFALL: Heavy rainfall associated with Tropical Depression
Fifteen-E will begin to affect the eastern portions of Hawaii
Wednesday. Periods of heavy rain are likely to continue across the
Big Island and Maui through the weekend. Life-threatening,
catastrophic flooding and mudslides are possible, especially in
areas of steep terrain. Across the remainder of Hawaii, lesser
rainfall totals are expected, with isolated flooding possible.
SURF: Swells generated by Tropical Depression Fifteen-E are
expected to reach the east and south-facing shores of the Big Island
on Friday, spreading westward and building through the weekend.
These swells are likely to cause life-threatening surf and rip
current conditions. Please consult products from your local weather
office.
NEXT ADVISORY
-------------
Next complete advisory at 500 AM HST.
$$
Forecaster Kelly/Cangialosi
000
WTPA42 PHFO 230844
TCDCP2
Tropical Depression Fifteen-E Discussion Number 11
NWS Central Pacific Hurricane Center Honolulu HI EP152026
Issued by NWS National Hurricane Center Miami FL
1100 PM HST Tue Sep 22 2026
Recent satellite imagery indicates that the low-level circulation
associated with the remnants of former Tropical Depression Fifteen-E
has once again become well-defined as the system crossed from the
western East Pacific basin into the central Pacific basin. There has
been persistent deep convection, mainly in a band to the north and
west of the low-level center. Since the remnants have maintained
trackable with continuity for over a week since losing its tropical
cyclone status, advisories are being re-initiated and the system
will retain its original designation as Tropical Depression
Fifteen-E. The initial intensity is set at 30 kt and is based on the
latest objective intensity estimates from UW-CIMSS. It is worth
noting that if the cyclone becomes a tropical storm, it will receive
the Central Pacific name Nolo.
The depression is moving west-northwestward at about 10 kt on the
southwest side of a low- to mid-level ridge. This ridge is expected
to shift eastward and weaken while a mid- to upper-level low dives
southwestward near the northwestern Hawaiian Islands. This pattern
change should cause the cyclone to slow down and then turn northward
or north-northeastward later this week. That motion should take the
cyclone near the Big Island of Hawaii late Friday or on Saturday.
Around that time, the upper low is expected to weaken and move
westward, allowing mid-level ridging to become re-established to the
north of the system. In response, the cyclone should turn and then
accelerate westward. The NHC track forecast is closest to the
best-performing models of the year so far, HCCA and GDMI. Given the
complex steering evolution and significant model spread, confidence
in the details of the track forecast is low. Interests in the
Hawaiian Islands, especially on the Big Island, should closely
monitor the system.
The environmental conditions are favorable for strengthening over
the next few days with vertical wind shear expected to be around or
less than 10 kt, high mid-level humidities, and SSTs of around 29
C. The only limiting factor is the system's sprawling low-level
structure. Considering these conditions, the NHC intensity forecast
calls for slow strengthening to start, followed by more significant
intensification when the system moves toward Hawaii. Most of the
reliable intensity models are quite aggressive, and the NHC
intensity forecast follows a combination of the HAFS guidance and
HCCA and GDMI aids. This prediction shows the system becoming a
hurricane in a couple of days and nearing major hurricane strength
when it approaches the Big Island of Hawaii by the weekend.
Key Messages:
1. Tropical Depression Fifteen-E is expected to strengthen into a
tropical storm on Wednesday and a hurricane in a couple of days as
it turns northward. Although it is too soon to specify the exact
location and magnitude of impacts, interests in Hawaii should
closely monitor the latest forecast updates and ensure that they
have their preparedness plan in place.
2. Heavy rainfall associated with Tropical Depression Fifteen-E will
begin to affect the eastern portions of Hawaii Wednesday. Periods of
heavy rain are likely to continue across the Big Island and Maui
through Saturday. Life-threatening, catastrophic flooding and
mudslides are possible from rainfall totals in excess of a foot,
especially in areas of steep terrain. Across the remainder of
Hawaii, lesser rainfall totals are expected, with isolated flooding
possible.
3. There is an increasing risk of wind and wave impacts in the
Hawaiian Islands regardless of the exact track and intensity of the
system. Hurricane or Tropical Storm Watches may be required for
portions of the Hawaiian Islands on Wednesday.
FORECAST POSITIONS AND MAX WINDS
INIT 23/0900Z 14.0N 153.7W 30 KT 35 MPH
12H 23/1800Z 14.4N 154.7W 35 KT 40 MPH
24H 24/0600Z 14.6N 155.5W 45 KT 50 MPH
36H 24/1800Z 15.0N 155.6W 55 KT 65 MPH
48H 25/0600Z 15.9N 155.2W 70 KT 80 MPH
60H 25/1800Z 17.0N 154.9W 85 KT 100 MPH
72H 26/0600Z 17.9N 154.7W 95 KT 110 MPH
96H 27/0600Z 18.3N 156.0W 95 KT 110 MPH
120H 28/0600Z 18.2N 159.0W 95 KT 110 MPH
$$
Forecaster Kelly/Cangialosi