...ISELLE STRENGTHENS SLIGHTLY...
 
 
SUMMARY OF 200 AM PDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...17.8N 116.2W
ABOUT 540 MI...865 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...NW OR 315 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES
 
 
WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.
 
 
DISCUSSION AND OUTLOOK
----------------------
At 200 AM PDT (0900 UTC), the center of Tropical Storm Iselle was
located near latitude 17.8 North, longitude 116.2 West. Iselle is
moving toward the northwest near 12 mph (19 km/h) and this motion is
expected to continue through tonight, followed by a gradual turn
toward the west-northwest on Tuesday.
 
Maximum sustained winds have increased to near 60 mph (95 km/h) with 
higher gusts. Some strengthening is expected over the next day or 
so, and Iselle could become a short-lived hurricane by late tonight. 
Gradual weakening is then forecast starting on Tuesday. 
 
Tropical-storm-force winds extend outward up to 125 miles (205 km)
from the center.
 
The estimated minimum central pressure is 996 mb (29.42 inches).
 
 
HAZARDS AFFECTING LAND
----------------------
SURF: Swells generated by Iselle will affect the west coast of the
Baja California Peninsula beginning today. 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 800 AM PDT.

TROPICAL STORM ISELLE FORECAST/ADVISORY NUMBER   4
NWS NATIONAL HURRICANE CENTER MIAMI FL       EP092026
0900 UTC MON AUG 24 2026
 
TROPICAL STORM CENTER LOCATED NEAR 17.8N 116.2W AT 24/0900Z
POSITION ACCURATE WITHIN  40 NM
 
PRESENT MOVEMENT TOWARD THE NORTHWEST OR 315 DEGREES AT  10 KT
 
ESTIMATED MINIMUM CENTRAL PRESSURE  996 MB
MAX SUSTAINED WINDS  50 KT WITH GUSTS TO  60 KT.
50 KT....... 40NE  40SE   0SW   0NW.
34 KT.......100NE 100SE 110SW  60NW.
4 M SEAS....210NE 150SE  75SW 120NW.
WINDS AND SEAS VARY GREATLY IN EACH QUADRANT.  RADII IN NAUTICAL
MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT.
 
REPEAT...CENTER LOCATED NEAR 17.8N 116.2W AT 24/0900Z
AT 24/0600Z CENTER WAS LOCATED NEAR 17.6N 115.8W
 
FORECAST VALID 24/1800Z 19.0N 117.4W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 50NE  40SE   0SW  20NW.
34 KT...100NE 100SE  90SW  80NW.
 
FORECAST VALID 25/0600Z 20.1N 118.9W
MAX WIND  65 KT...GUSTS  80 KT.
64 KT... 20NE   0SE   0SW   0NW.
50 KT... 50NE  40SE   0SW  30NW.
34 KT...110NE 110SE  80SW  90NW.
 
FORECAST VALID 25/1800Z 20.9N 120.7W
MAX WIND  60 KT...GUSTS  75 KT.
50 KT... 50NE  30SE   0SW  30NW.
34 KT...120NE 100SE  80SW 100NW.
 
FORECAST VALID 26/0600Z 21.5N 122.5W
MAX WIND  55 KT...GUSTS  65 KT.
50 KT... 40NE  30SE   0SW  30NW.
34 KT...100NE  80SE  60SW 100NW.
 
FORECAST VALID 26/1800Z 21.9N 124.4W
MAX WIND  50 KT...GUSTS  60 KT.
50 KT... 30NE   0SE   0SW  30NW.
34 KT... 80NE  60SE  50SW  80NW.
 
FORECAST VALID 27/0600Z 22.4N 126.3W
MAX WIND  45 KT...GUSTS  55 KT.
34 KT... 60NE  40SE  30SW  60NW.
 
EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM
ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY
 
OUTLOOK VALID 28/0600Z 23.1N 130.1W
MAX WIND  35 KT...GUSTS  45 KT.
34 KT... 30NE   0SE   0SW  40NW.
 
OUTLOOK VALID 29/0600Z 23.9N 134.1W...POST-TROP/REMNT LOW
MAX WIND  30 KT...GUSTS  40 KT.
 
REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 17.8N 116.2W
 
NEXT ADVISORY AT 24/1500Z

Expires:No;;271694
WTPZ44 KNHC 240851
TCDEP4
 
Tropical Storm Iselle Discussion Number   4
NWS National Hurricane Center Miami FL       EP092026
200 AM PDT Mon Aug 24 2026
 
Iselle is being affected by northwesterly shear, with much of the 
deep convection displaced to the south and east of the center. Over 
the past several hours, the convective structure has evolved, with 
curved banding becoming increasingly established around the center. 
The latest Dvorak intensity estimate from TAFB at 0600 UTC was 
3.0/45 kt; however, recent objective intensity estimates from 
UW-CIMSS have increased and range from 43-59 kt. Given the improved 
banding evident on satellite imagery and the upward trend in 
objective intensity estimates, the initial intensity is set at 50 kt 
for this advisory. 

The tropical storm is moving northwestward around 10 kt, steered by 
a mid-level ridge centered over the southwestern United States. 
Iselle is forecast to turn toward the west-northwest as the ridge 
expands westward into the eastern Pacific, and this general motion 
is expected through much of this week. The latest NHC forecast is 
very similar to the previous advisory and lies near the middle of 
the track guidance envelope, closest to the HFIP Corrected Consensus 
(HCCA) and the Google DeepMind (GDMI) model. There is considerable 
spread among the guidance during the latter portion of the forecast 
period, resulting in slightly below-average confidence in the track 
forecast. 

Iselle is moving over warm waters around 29-30 C and remains within 
a fairly moist mid-level environment, which should support gradual 
strengthening during the next 12-24 h. The latest NHC forecast 
brings Iselle to hurricane strength during this period, near the 
upper end of the intensity guidance, and is consistent with HCCA and 
GDM. Beyond 24 h, increasing wind shear, cooler waters and 
progressively drier mid-level air are expected to lead to gradual 
weakening from Tuesday through the remainder of the week. The ECMWF 
and GFS simulated satellite imagery suggest that Iselle may struggle 
to maintain organized convection by late this week, raising the 
possibility that the cyclone could become post-tropical earlier than 
currently forecast. 
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  24/0900Z 17.8N 116.2W   50 KT  60 MPH
 12H  24/1800Z 19.0N 117.4W   60 KT  70 MPH
 24H  25/0600Z 20.1N 118.9W   65 KT  75 MPH
 36H  25/1800Z 20.9N 120.7W   60 KT  70 MPH
 48H  26/0600Z 21.5N 122.5W   55 KT  65 MPH
 60H  26/1800Z 21.9N 124.4W   50 KT  60 MPH
 72H  27/0600Z 22.4N 126.3W   45 KT  50 MPH
 96H  28/0600Z 23.1N 130.1W   35 KT  40 MPH
120H  29/0600Z 23.9N 134.1W   30 KT  35 MPH...POST-TROP/REMNT LOW