Overall Green Tropical Cyclone for HERNAN-26 Off-shore from 13 Aug 2026 03:00 UTC to 09:00

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Overall Green Tropical Cyclone for HERNAN-26

Off-shore

Global Telecommunication Service

GTS (Global Telecommunication Service) is the official Warning and Alerting channel by the World Meteorological Organization (WMO) adopted by several Warning Organizations. As soon as a new GTS message regarding Tropical Cyclones(WT) or Tsunami(WE) the messages are processed and possibly assigned to the specific event. When a new GTS message is present an new tab in the specific event report page is present.The presence of a GTS message is shown in the homepage with a dedicated icon.

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Measurements Levels

SOURCE	GAUGE LOCATION	LAT	LON	TIME (UTC)	HEIGHT (m)	PERIOD (min)

13/08 08:42 WTPZ43KNHC130839

13/08 08:40 WTPZ33KNHC130838

13/08 08:39 WTPZ23KNHC130838

13/08 02:53 WTPZ43KNHC130251

13/08 02:52 WTPZ33KNHC130250

13/08 02:50 WTPZ23KNHC130249

Original Message :

WTPZ43 KNHC 130839
TCDEP3

Tropical Storm Hernan Discussion Number 2
NWS National Hurricane Center Miami FL EP082026
200 AM PDT Thu Aug 13 2026

A recent ASCAT pass has shown that the winds have increased on
the western side of the cyclone to around 35 kts. While the most
recent TAFB Dvorak fix has a Final T 2.0 with a max winds of 30
kt. DPRINT has a wind maximum around 39 kt while the ADT and AiDT
are close to 32 and 33 kt respectively. Based on the observations
from the ASCAT, the initial NHC intensity has been set to 35 kt.

The initial motion is estimated to be west, or 270 degrees at 3 kt.
As a trough near the west coast of the U.S. pulls away and some
weak ridging builds back in to the north, the cyclone should
gradually turn toward the southwest as it feels a tug from lower
pressures to the southwest of the system. The current NHC forecast
track is adjusted slightly to the right of the previous track, but
generally still in the middle of the spread in the models and close
to HCCA. However, given that the track guidance still has a large
spread, the track confidence is still a bit below average.

The cyclone is experiencing moderate to strong westerly wind shear,
mainly due to the aforementioned trough to the north and outflow
from Potential Tropical Cyclone One-C. Therefore, at best only
minor additional strengthening appears likely, and the most likely
scenario is that the wind shear will prevent any additional
strengthening. Models forecast the environment to remain
unfavorable and that the storm may well degenerate to a remnant low
within 48 h. Indeed, the GFS and ECMWF simulated satellite imagery
indicate that it could a remnant low sooner than currently
forecast. The remnants should gradually spin down and dissipate in a
few days.

FORECAST POSITIONS AND MAX WINDS

INIT 13/0900Z 18.1N 131.9W 35 KT 40 MPH
12H 13/1800Z 18.0N 132.0W 35 KT 40 MPH
24H 14/0600Z 17.3N 132.4W 35 KT 40 MPH
36H 14/1800Z 16.5N 132.9W 30 KT 35 MPH
48H 15/0600Z 15.8N 133.7W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 15/1800Z 15.3N 135.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 16/0600Z 14.9N 136.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 17/0600Z...DISSIPATED

$$
Forecaster Katz/Beven

Original Message :

WTPZ33 KNHC 130838
TCPEP3

BULLETIN
TROPICAL STORM HERNAN ADVISORY NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082026
200 AM PDT THU AUG 13 2026

...TROPICAL DEPRESSION BECOMES TROPICAL STORM HERNAN OVER THE EAST
PACIFIC...

SUMMARY OF 200 AM PDT...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...18.1N 131.9W
ABOUT 1460 MI...2350 KM W OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...W OR 270 DEGREES AT 2 MPH...4 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 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 HERNAN WAS
LOCATED NEAR LATITUDE 18.1 NORTH, LONGITUDE 131.9 WEST. HERNAN IS
MOVING TOWARD THE WEST NEAR 2 MPH (4 KM/H). A GRADUAL TURN TO THE
SOUTHWEST IS EXPECTED OVER THE NEXT DAY OR SO.

MAXIMUM SUSTAINED WINDS ARE NEAR 40 MPH (65 KM/H) WITH HIGHER GUSTS.
SLIGHT STRENGTHENING IS POSSIBLE THROUGH TONIGHT. WEAKENING IS
EXPECTED TO BEGIN BY FRIDAY.

TROPICAL-STORM-FORCE WINDS EXTEND OUTWARD UP TO 40 MILES (65 KM)
FROM THE CENTER.

THE ESTIMATED MINIMUM CENTRAL PRESSURE IS 1006 MB (29.71 INCHES).

HAZARDS AFFECTING LAND
----------------------
NONE

NEXT ADVISORY
-------------
NEXT COMPLETE ADVISORY AT 800 AM PDT.

$$
FORECASTER KATZ/BEVEN=

Original Message :

WTPZ23 KNHC 130838
TCMEP3

TROPICAL STORM HERNAN FORECAST/ADVISORY NUMBER 2
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082026
0900 UTC THU AUG 13 2026

TROPICAL STORM CENTER LOCATED NEAR 18.1N 131.9W AT 13/0900Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST OR 270 DEGREES AT 2 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1006 MB
MAX SUSTAINED WINDS 35 KT WITH GUSTS TO 45 KT.
34 KT....... 0NE 0SE 30SW 35NW.
4 M SEAS.... 0NE 0SE 60SW 60NW.
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 18.1N 131.9W AT 13/0900Z
AT 13/0600Z CENTER WAS LOCATED NEAR 18.1N 131.8W

FORECAST VALID 13/1800Z 18.0N 132.0W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 0NE 0SE 20SW 30NW.

FORECAST VALID 14/0600Z 17.3N 132.4W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 0NE 0SE 10SW 20NW.

FORECAST VALID 14/1800Z 16.5N 132.9W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 15/0600Z 15.8N 133.7W...POST-TROP/REMNT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 15/1800Z 15.3N 135.3W...POST-TROP/REMNT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 16/0600Z 14.9N 136.8W...POST-TROP/REMNT LOW
MAX WIND 20 KT...GUSTS 30 KT.

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 17/0600Z...DISSIPATED

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.1N 131.9W

NEXT ADVISORY AT 13/1500Z

$$
FORECASTER KATZ/BEVEN=

Original Message :

WTPZ43 KNHC 130251
TCDEP3

Tropical Depression Eight-E Discussion Number 1
NWS National Hurricane Center Miami FL EP082026
800 PM PDT Wed Aug 12 2026

Scatterometer passes over the past day or so have indicated that
Invest 99E has had a closed, well-defined circulation during that
time, including a recent OSCAT pass. Deep convection has pulsed up
and down over the past day, but has recently been persisting
well-enough for the past 6 hours to be classified as a tropical
cyclone. The latest subjective Dvorak fix from TAFB is 1.5/25 kt,
but wind vectors from OSCAT, as well as the ASCAT pass from
yesterday, suggest that it likely has winds near 30 kt, and that is
the initial NHC intensity for this advisory.

The initial motion is estimated to be west-northwestward, or 300
degrees at 6 kt. As a trough near the west coast of the U.S. pulls
away and some weak ridging builds back in to the north, the cyclone
should gradually turn toward the southwest as it feels a tug from
lower pressures toward the southwest of the system. The NHC
forecast lies near, but slightly south of, the latest HFIP corrected
consensus (HCCA) model. The spread in the models is a little
greater than average, so the confidence in the track forecast is a
bit below average.

The cyclone is experiencing moderate to strong westerly wind shear,
mainly due to the aforementioned trough to the north and outflow
from Potential Tropical Cyclone One-C. Therefore, very little
strengthening is likely. The NHC forecast calls for a peak
intensity of 35 kt in 12-24 hours, which is near the high end of the
intensity guidance suite. Thereafter, although shear may decrease
some as that trough pulls away, mid-level humidities are expected to
decrease at the same time, and model guidance suggests there may not
be much left of the cyclone by 48 h. The NHC forecast calls for the
system to become a remnant low in 48 h, but GFS and ECMWF simulated
satellite imagery indicate it could become a remnant low even sooner
than forecast. After that, model guidance shows the system
gradually spinning down and dissipating in about 3 days.

FORECAST POSITIONS AND MAX WINDS

INIT 13/0300Z 18.1N 131.7W 30 KT 35 MPH
12H 13/1200Z 18.2N 131.9W 35 KT 40 MPH
24H 14/0000Z 17.9N 132.3W 35 KT 40 MPH
36H 14/1200Z 17.0N 132.7W 30 KT 35 MPH
48H 15/0000Z 16.2N 133.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 15/1200Z 15.5N 134.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 16/0000Z 15.2N 136.1W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 17/0000Z...DISSIPATED

$$
Forecaster Hagen

Original Message :

WTPZ33 KNHC 130250
TCPEP3

BULLETIN
Tropical Depression Eight-E Advisory Number 1
NWS National Hurricane Center Miami FL EP082026
800 PM PDT Wed Aug 12 2026

...NEW TROPICAL DEPRESSION FORMS OVER THE OPEN WATERS OF THE EAST
PACIFIC...

SUMMARY OF 800 PM PDT...0300 UTC...INFORMATION
----------------------------------------------
LOCATION...18.1N 131.7W
ABOUT 1445 MI...2330 KM W OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 7 MPH...11 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES

WATCHES AND WARNINGS
--------------------
There are no coastal watches or warnings in effect.

DISCUSSION AND OUTLOOK
----------------------
At 800 PM PDT (0300 UTC), the center of Tropical Depression Eight-E
was located near latitude 18.1 North, longitude 131.7 West. The
depression is moving toward the west-northwest near 7 mph (11 km/h).
A gradual turn to the west and southwest is expected over the next
day or so.

Maximum sustained winds are near 35 mph (55 km/h) with higher gusts.
Some slight strengthening is possible during the next day or so, and
the depression could become a tropical storm by Thursday. Weakening
is expected to begin by Friday.

The estimated minimum central pressure is 1006 mb (29.71 inches).

HAZARDS AFFECTING LAND
----------------------
None

NEXT ADVISORY
-------------
Next complete advisory at 200 AM PDT.

$$
Forecaster Hagen

Original Message :

WTPZ23 KNHC 130249
TCMEP3

TROPICAL DEPRESSION EIGHT-E FORECAST/ADVISORY NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL EP082026
0300 UTC THU AUG 13 2026

TROPICAL DEPRESSION CENTER LOCATED NEAR 18.1N 131.7W AT 13/0300Z
POSITION ACCURATE WITHIN 30 NM

PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 300 DEGREES AT 6 KT

ESTIMATED MINIMUM CENTRAL PRESSURE 1006 MB
MAX SUSTAINED WINDS 30 KT WITH GUSTS TO 40 KT.
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 18.1N 131.7W AT 13/0300Z
AT 13/0000Z CENTER WAS LOCATED NEAR 18.0N 131.7W

FORECAST VALID 13/1200Z 18.2N 131.9W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 30NE 0SE 0SW 30NW.

FORECAST VALID 14/0000Z 17.9N 132.3W
MAX WIND 35 KT...GUSTS 45 KT.
34 KT... 0NE 0SE 0SW 30NW.

FORECAST VALID 14/1200Z 17.0N 132.7W
MAX WIND 30 KT...GUSTS 40 KT.

FORECAST VALID 15/0000Z 16.2N 133.2W...POST-TROP/REMNT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 15/1200Z 15.5N 134.4W...POST-TROP/REMNT LOW
MAX WIND 25 KT...GUSTS 35 KT.

FORECAST VALID 16/0000Z 15.2N 136.1W...POST-TROP/REMNT LOW
MAX WIND 20 KT...GUSTS 30 KT.

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 17/0000Z...DISSIPATED

REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 18.1N 131.7W

NEXT ADVISORY AT 13/0900Z

$$
FORECASTER HAGEN=

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