EPAC: JULIETTE - Post-Tropical - Discussion

[Subtrop]

EP, 92, 2025082400, , BEST, 0, 141N, 1054W, 25, 1007, DB, 34, NEQ, 0, 0, 0, 0, 1010, 180, 90, 0, 0, E, 0, , 0, 0, INVEST, S, 0, , 0, 0, 0, 0, genesis-num, 019, SPAWNINVEST, ep712025 to ep922025,

https://ftp.nhc.noaa.gov/atcf/btk/bep922025.dat

[StormWeather]

Tropical Depression Ten-E Advisory Number 1
NWS National Hurricane Center Miami FL EP102025
200 PM MST Sun Aug 24 2025

...NEW EAST PACIFIC TROPICAL DEPRESSION FORMS...


SUMMARY OF 200 PM MST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...16.0N 109.7W
ABOUT 475 MI...765 KM S OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...35 MPH...55 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...1006 MB...29.71 INCHES




Tropical Depression Ten-E Discussion Number 1
NWS National Hurricane Center Miami FL EP102025
200 PM MST Sun Aug 24 2025

Data from both the ASCAT-B and ASCAT-C scatterometers indicate that
the broad area of low pressure located well offshore of the
southwestern coast of Mexico now has a well-defined circulation.
The deep convection has been forming a rudimentary banding
structure over the western semicircle of the circulation. Thus,
the system is being designated as Tropical Depression Ten-E at this
time. The scatterometer observations indicate that the system is
just below tropical storm strength, and the intensity estimate is
in good agreement with a Dvorak estimate from TAFB.

The initial motion estimate is west-northwestward, or 290/12 kt. A
mid-level ridge is expected to remain to the northeast of the
tropical cyclone during the next few days. This steering pattern
should cause a west-northwestward to northwestward track for most
of the forecast period. In 4-5 days, the weakening cyclone is
expected turn more westward in the low-level flow. The official
track forecast lies between the NOAA corrected consensus, HCCA,
model and the Google Deep Mind, GDMI, predictions.

The cyclone is currently over warm waters within moderate
northeasterly vertical wind shear. Although the shear is predicted
to lessen over the next couple of days, gradually cooling ocean
waters should partially offset the more conducive wind
environment. Therefore, only modest strengthening is forecast, and
the NHC prediction is roughly in the middle of the model guidance.
Around the end of the forecast period, significantly lower SSTs are
likely to reduce the system to a remnant low.


FORECAST POSITIONS AND MAX WINDS

INIT 24/2100Z 16.0N 109.7W 30 KT 35 MPH
12H 25/0600Z 16.7N 111.4W 35 KT 40 MPH
24H 25/1800Z 17.7N 113.5W 40 KT 45 MPH
36H 26/0600Z 18.7N 115.5W 45 KT 50 MPH
48H 26/1800Z 19.7N 117.3W 45 KT 50 MPH
60H 27/0600Z 21.0N 118.8W 45 KT 50 MPH
72H 27/1800Z 22.4N 120.0W 40 KT 45 MPH
96H 28/1800Z 24.5N 121.5W 30 KT 35 MPH
120H 29/1800Z 25.0N 122.5W 25 KT 30 MPH...POST-TROP/REMNT LOW

[Sciencerocks]

[cycloneye]

EP, 10, 2025082500, , BEST, 0, 162N, 1101W, 30, 1005, TD

[cycloneye]

Tropical Depression Ten-E Discussion Number 2
NWS National Hurricane Center Miami FL EP102025
800 PM MST Sun Aug 24 2025

The depression has changed little over the past several hours, and
it continues to maintain a broad structure with numerous bands of
deep convection. The convection, however, is not particularly well
organized and remains confined to the western half of the
circulation due to moderate northeasterly vertical wind shear. The
initial intensity remains 30 kt based on a blend of the latest
satellite estimates.

Tropical Depression Ten-E is moving west-northwestward at 11 kt on
the south side of a subtropical high. This general motion is
expected to continue during the next day or so as the steering
pattern persists. After that time, a gradual turn to the northwest
and then the north-northwest is forecast as the system moves into a
weakness within the subtropical ridge. The NHC track forecast is
similar to the previous one, and lies near the middle of the
guidance envelope.

The shear over the system is expected to lessen soon, and that
should allow the cyclone to strengthen over the next day or two.
However, any strengthening is likely to be short-lived as the system
is expected to move over sub 26C waters in about 48 hours. The
expected track over cooler water combined with a progressively drier
airmass should cause a weakening trend, and ultimately lead to the
system becoming a post-tropical low in about 4 days. The NHC
intensity forecast is slightly higher than the previous one and lies
fairly close to the IVCN consensus aid.


FORECAST POSITIONS AND MAX WINDS

INIT 25/0300Z 16.5N 110.6W 30 KT 35 MPH
12H 25/1200Z 17.2N 112.2W 35 KT 40 MPH
24H 26/0000Z 18.2N 114.2W 40 KT 45 MPH
36H 26/1200Z 19.2N 116.1W 45 KT 50 MPH
48H 27/0000Z 20.4N 117.9W 50 KT 60 MPH
60H 27/1200Z 21.7N 119.2W 45 KT 50 MPH
72H 28/0000Z 23.0N 120.2W 40 KT 45 MPH
96H 29/0000Z 25.0N 121.5W 30 KT 35 MPH...POST-TROP/REMNT LOW
120H 30/0000Z 26.3N 122.2W 25 KT 30 MPH...POST-TROP/REMNT LOW

$$
Forecaster Cangialosi

[Kingarabian]

Likely a TS. Deep convection west of the center

[Sciencerocks]

[StormWeather]

Welcome Juliette.

Tropical Storm Juliette Advisory Number 3
NWS National Hurricane Center Miami FL EP102025
200 AM MST Mon Aug 25 2025

...DEPRESSION STRENGTHENS TO TENTH TROPICAL STORM OF THE 2025 EAST
PACIFIC HURRICANE SEASON...


SUMMARY OF 200 AM MST...0900 UTC...INFORMATION
----------------------------------------------
LOCATION...16.8N 111.8W
ABOUT 440 MI...705 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...40 MPH...65 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES



Tropical Storm Juliette Discussion Number 3
NWS National Hurricane Center Miami FL EP102025
200 AM MST Mon Aug 25 2025

Since the time of the previous NHC advisory, the sheared convective
burst associated with the tropical cyclone has grown larger, with a
large area of cloud tops colder than -80C on GOES-West infrared
imagery. Furthermore, the low level center, which had been exposed
to the east of the burst, appears to have moved underneath the
eastern edge of the convection. This suggests the moderate
northeasterly vertical wind shear is weakening. The UW-CIMSS
objective intensity estimates have been steadily increasing, and
are now in the 32-35 kt range. TAFB provided a subjective Dvorak
estimate of 35 kt, and an ASCAT pass from 25/0441 UTC showed a few
35 kt vectors in the deep convection that might have been a bit
rain-inflated. Regardless of the accuracy of the ASCAT data, given
the improving satellite presentation and persistence of the large,
cold convective mass, the depression is upgraded to Tropical Storm
Juliette with a 35-kt intensity.

Juliette is moving west-northwestward, or 290/11 kt on the south
side of a subtropical high. This general motion is expected to
continue during the next day or so. After that time, a gradual
turn to the northwest is forecast as the system is influenced by a
weakness in the subtropical ridge. The model guidance has shifted
to the left and a bit faster compared to the previous cycle, and so
has the NHC forecast. The latest official forecast is in best
agreement with the HFIP corrected consensus (HCCA) model. Spread
in the model guidance increases by day 3, and the NHC forecast
shows the cyclone slowing down at that time, similar to consensus
aids.

Environmental conditions appear favorable for Juliette to strengthen
for at least 36-42 more hours. The 10-kt northeasterly vertical
shear being experienced by the cyclone should diminish to single
digits later today, while the system traverses warm ocean waters.
By 48 h, Juliette should reach colder waters and a more stable
atmosphere, and these conditions will induce weakening. The latest
NHC intensity forecast is slightly higher than the previous one and
lies at the high end of the model guidance at 36-48 h. The reason
for this is that with the shift in the forecast track to the left,
Juliette should have a few additional hours to strengthen before it
reaches the less favorable conditions. With the decreasing shear
later today, there should be enough time for Juliette to become a
high-end tropical storm.


FORECAST POSITIONS AND MAX WINDS

INIT 25/0900Z 16.8N 111.8W 35 KT 40 MPH
12H 25/1800Z 17.5N 113.5W 40 KT 45 MPH
24H 26/0600Z 18.4N 115.5W 45 KT 50 MPH
36H 26/1800Z 19.4N 117.3W 55 KT 65 MPH
48H 27/0600Z 20.6N 118.9W 55 KT 65 MPH
60H 27/1800Z 21.9N 120.2W 45 KT 50 MPH
72H 28/0600Z 23.2N 121.1W 35 KT 40 MPH
96H 29/0600Z 25.0N 122.1W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 30/0600Z 25.9N 122.9W 20 KT 25 MPH...POST-TROP/REMNT LOW

$$
Forecaster Hagen

[cycloneye]

Tropical Storm Juliette Advisory Number 4
NWS National Hurricane Center Miami FL EP102025
800 AM MST Mon Aug 25 2025

...JULIETTE A LITTLE STRONGER...


SUMMARY OF 800 AM MST...1500 UTC...INFORMATION
----------------------------------------------
LOCATION...17.1N 113.1W
ABOUT 180 MI...290 KM SW OF SOCORRO ISLAND
ABOUT 450 MI...725 KM SSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 13 MPH...20 KM/H
MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES



Tropical Storm Juliette Discussion Number 4
NWS National Hurricane Center Miami FL EP102025
800 AM MST Mon Aug 25 2025

Deep convection, with a fair amount of lightning, continues to
burst over Juliette's center. There still appears to be some shear
affecting the cyclone, although various diagnostics from UW-CIMSS
and SHIPS suggest it has decreased to about 10 kt. Objective
satellite intensity estimates are gradually increasing, and the
maximum winds are estimated to now be 40 kt. With the shear now
lower, steady intensification is anticipated during the next 36
hours or so while Juliette remains over waters warmer than 26
degrees Celsius. The NHC intensity forecast is at the top end of
the guidance during this period. Weakening is forecast after 36
hours due to cooler waters and a drier, more stable atmosphere. The
NHC forecast calls for Juliette to become post-tropical by Friday,
although it could happen as early as Thursday.

Juliette continues west-northwestward (290 degrees) at 11 kt. Due
to a break in the subtropical ridge which has developed near and to
the west of the Baja California peninsula, Juliette is expected to
gradually turn toward the northwest on Tuesday, and then the
north-northwest and north by Thursday and Friday. There is a
typical amount of spread among the track guidance, and the NHC
forecast takes a blend of the HCCA, Florida State Superensemble,
Google Deep Mind, and TVCE consensus aids. This updated forecast
is not too different from the previous prediction.


FORECAST POSITIONS AND MAX WINDS

INIT 25/1500Z 17.1N 113.1W 40 KT 45 MPH
12H 26/0000Z 17.9N 114.7W 45 KT 50 MPH
24H 26/1200Z 18.8N 116.5W 50 KT 60 MPH
36H 27/0000Z 20.1N 118.2W 55 KT 65 MPH
48H 27/1200Z 21.6N 119.6W 50 KT 60 MPH
60H 28/0000Z 23.0N 120.7W 40 KT 45 MPH
72H 28/1200Z 24.2N 121.4W 35 KT 40 MPH
96H 29/1200Z 26.0N 121.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 30/1200Z 26.2N 122.3W 15 KT 15 MPH...POST-TROP/REMNT LOW

$$
Forecaster Berg

[Sciencerocks]

[cycloneye]

BULLETIN
Tropical Storm Juliette Advisory Number 5
NWS National Hurricane Center Miami FL EP102025
200 PM MST Mon Aug 25 2025

...JULIETTE CONTINUES TO STRENGTHEN...


SUMMARY OF 200 PM MST...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...17.6N 114.5W
ABOUT 245 MI...395 KM WSW OF SOCORRO ISLAND
ABOUT 470 MI...760 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...60 MPH...95 KM/H
PRESENT MOVEMENT...WNW OR 290 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...999 MB...29.50 INCHES



Tropical Storm Juliette Discussion Number 5
NWS National Hurricane Center Miami FL EP102025
200 PM MST Mon Aug 25 2025

A recent ASCAT-B scatterometer pass revealed that Juliette is now
producing maximum winds around 50 kt within the southeastern
quadrant. The center is well embedded beneath a persistent burst
of deep convection, but interestingly, the cyclone has also been
producing another semi-disconnected burst of convection to the
southwest of the center. Juliette has another 24-36 hours before
it reaches cooler waters and a drier, more stable atmosphere.
Continued strengthening is expected in the short term, and Juliette
does have the potential to become a hurricane. In fact, the
latest SHIPS Rapid Intensification indices are showing a 40-45
percent change of a 25-kt increase over the next day. The NHC
forecast therefore explicitly shows Juliette becoming a hurricane
in 24 hours. Weakening is anticipated to begin in 36 hours, and
Juliette could become post-tropical in about 3 days when it loses
its deep convection. Dissipation into a trough is likely by day 5.

The initial motion is west-northwestward (290 degrees) at 12 kt.
Due to a break in the subtropical ridge which has developed near
and to the west of the Baja California peninsula, Juliette is
expected to gradually turn toward the northwest on Tuesday, and then
the north-northwest by late Wednesday. The NHC largely follows a
blend of the previous forecast and the Google Deep Mind model, but
overall there isn't much spread in the track guidance.


FORECAST POSITIONS AND MAX WINDS

INIT 25/2100Z 17.6N 114.5W 50 KT 60 MPH
12H 26/0600Z 18.3N 116.0W 60 KT 70 MPH
24H 26/1800Z 19.3N 117.7W 65 KT 75 MPH
36H 27/0600Z 20.6N 119.2W 60 KT 70 MPH
48H 27/1800Z 22.2N 120.6W 55 KT 65 MPH
60H 28/0600Z 23.5N 121.5W 45 KT 50 MPH
72H 28/1800Z 24.5N 122.0W 35 KT 40 MPH...POST-TROPICAL
96H 29/1800Z 25.7N 122.5W 25 KT 30 MPH...POST-TROP/REMNT LOW
120H 30/1800Z...DISSIPATED

$$
Forecaster Berg

[Sciencerocks]

[zhukm29]

[Kingarabian]

Likely a hurricane now. AMSR2 had a solid mid levels eye.

[Kingarabian]

Dry air doing its thing now

[cycloneye]

BULLETIN
Tropical Storm Juliette Advisory Number 6
NWS National Hurricane Center Miami FL EP102025
800 PM PDT Mon Aug 25 2025

...JULIETTE COULD BECOME A HURRICANE ON TUESDAY...


SUMMARY OF 800 PM PDT...0300 UTC...INFORMATION
----------------------------------------------
LOCATION...17.8N 115.5W
ABOUT 305 MI...490 KM WSW OF SOCORRO ISLAND
ABOUT 505 MI...815 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 14 MPH...22 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES



Tropical Storm Juliette Discussion Number 6
NWS National Hurricane Center Miami FL EP102025
800 PM PDT Mon Aug 25 2025

Juliette continues to strengthen. A microwave pass from a few hours
ago suggested that the storm was developing an inner core, and
recent infrared satellite images indicate that banding features are
increasing south of the center. The Dvorak estimates from TAFB, SAB,
and CIMSS have all increased to 3.5/55 kt, and therefore, the
initial wind speed is increased to that value.

Juliette is expected to remain in favorable conditions to strengthen
for about another day, and it seems likely that it will become a
hurricane on Tuesday. However, the strengthening trend should end by
Tuesday night when the storm is forecast to cross the 26 C SST
isotherm and then move into an environment of drier air and stronger
shear. Juliette is expected to become a remnant low in about 3 days
when it is forecast to be over cool 22 C waters, and dissipate
entirely this weekend. The NHC intensity forecast is a blend of the
HCCA and IVCN models.

The storm is moving west-northwestward at 12 kt on the southwest
side of a mid-level ridge. A gradual turn to the northwest and
then the north-northwest with a notable reduction in forward speed
is expected over the next few days as Juliette moves toward a
weakness in the ridge. The NHC track forecast is largely an update
of the previous one and lies on the western side of the guidance
envelope, in best agreement with EMXI and the Google DeepMind
models.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0300Z 17.8N 115.5W 55 KT 65 MPH
12H 26/1200Z 18.5N 116.8W 65 KT 75 MPH
24H 27/0000Z 19.8N 118.3W 65 KT 75 MPH
36H 27/1200Z 21.3N 119.7W 60 KT 70 MPH
48H 28/0000Z 22.8N 120.9W 50 KT 60 MPH
60H 28/1200Z 24.0N 121.6W 40 KT 45 MPH
72H 29/0000Z 24.9N 122.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 30/0000Z 25.6N 122.9W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 31/0000Z...DISSIPATED

$$
Forecaster Cangialosi

[cycloneye]

Tropical Storm Juliette Discussion Number 7
NWS National Hurricane Center Miami FL EP102025
200 AM PDT Tue Aug 26 2025

Juliette's satellite appearance has remained fairly steady overnight
with curved banding mainly to the south of the center. Recent
microwave imagery shows that Juliette is still trying to develop a
small inner core, which has not become better established since the
previous advisory. Unfortunately, scatterometer missed tonight given
the small size of the system it fell within the data gap. There is a
bit of a range from subjective and objective intensity estimates
this cycle between 44 to 65 kt. Using a blend of these estimates,
the initial intensity for this advisory is held at 55 kt.

The system is moving west-northwestward at an estimated motion of
290/ 11 kt. The storm is being steered along the southwestern edge
of a mid-level ridge located to the north. A gradual turn to the
northwest then north-northwest is anticipated as a weakness in the
ridge develops over the next couple of days. The NHC forecast track
was nudged slightly to the right in the short term between the
consensus aids on the right with Google DeepMind and EMXI on the
left.

Juliette should remain within a favorable environment, with warm sea
surface temperatures and light to moderate wind shear for the next
18-24 h , which will allow for some strengthening. However, by early
Wednesday the system will be crossing into cooler sea surface
temperatures, and into a drier airmass. Latest SHIPS model guidance
depicts wind shear also increases in about 48 h. The latest NHC
intensity forecast lies near the consensus aids, and shows some
strengthening possible today, although since the inner core has not
established, the peak intensity is now just below hurricane
strength. A gradual weakening trend is then forecast between 24-36
h, followed by a faster rate of weakening beyond 36 h. Juliette is
forecast to become a remnant low by 60 h, before opening into a
trough and dissipating by day 4.


FORECAST POSITIONS AND MAX WINDS

INIT 26/0900Z 18.3N 116.3W 55 KT 65 MPH
12H 26/1800Z 19.3N 117.4W 60 KT 70 MPH
24H 27/0600Z 20.8N 119.0W 55 KT 65 MPH
36H 27/1800Z 22.4N 120.4W 50 KT 60 MPH
48H 28/0600Z 23.6N 121.2W 40 KT 45 MPH
60H 28/1800Z 24.6N 121.9W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 29/0600Z 25.3N 122.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
96H 30/0600Z...DISSIPATED

[cycloneye]

BULLETIN
Tropical Storm Juliette Advisory Number 8
NWS National Hurricane Center Miami FL EP102025
800 AM PDT Tue Aug 26 2025

...JULIETTE A LITTLE STRONGER...


SUMMARY OF 800 AM PDT...1500 UTC...INFORMATION
----------------------------------------------
LOCATION...19.1N 116.5W
ABOUT 360 MI...580 KM W OF SOCORRO ISLAND
ABOUT 500 MI...805 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/H
PRESENT MOVEMENT...NW OR 320 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...994 MB...29.36 INCHES



Tropical Storm Juliette Discussion Number 8
NWS National Hurricane Center Miami FL EP102025
800 AM PDT Tue Aug 26 2025

Conventional satellite imagery and a recent GPM/GMI microwave pass
indicate that Juliette has become better organized during the
past few hours. Deep convection has increased near and to the east
of the surface center, and the GPM image revealed an impressive
tightly curved band wrapping around the center from the southwest.
Based on the cyclone's improved cloud pattern and the subjective
intensity estimates from TAFB and SAB, the initial intensity is
nudged upward to 60 kt.

Although not explicitly shown in the NHC forecast, there's still a
possibility that Juliette could briefly become a hurricane later
today, and a couple of the hurricane models are indicating this as
well. By Wednesday, however, a weakening trend is expected while
Juliette traverses progressively cooler oceanic surface
temperatures and moves into a more inhibiting surrounding
thermodynamic environment. Juliette is likely to degenerate into a
remnant low by Thursday night and open into a trough over the
weekend. The NHC intensity forecast is similar to the previous
advisory and resembles the IVCN intensity consensus aid.

Juliette's initial motion is estimated to be northwestward, or
320/9 kt along the southwestern periphery of a mid-level
subtropical ridge to the northeast. A slower north-northwestward
motion is expected late Wednesday in response to a growing weakness
in the aforementioned subtropical ridge. The official track
forecast is nudged a bit to the left of the previous one and
is close to the Google DeepMind ensemble and ECMWF deterministic
models.


FORECAST POSITIONS AND MAX WINDS

INIT 26/1500Z 19.1N 116.5W 60 KT 70 MPH
12H 27/0000Z 20.1N 117.6W 60 KT 70 MPH
24H 27/1200Z 21.6N 119.2W 55 KT 65 MPH
36H 28/0000Z 22.9N 120.5W 50 KT 60 MPH
48H 28/1200Z 24.0N 121.4W 40 KT 45 MPH
60H 29/0000Z 24.8N 122.0W 30 KT 35 MPH...POST-TROP/REMNT LOW
72H 29/1200Z 25.6N 122.7W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 30/1200Z...DISSIPATED

$$
Forecaster Roberts

NNNN

[cycloneye]

BULLETIN
Tropical Storm Juliette Advisory Number 9
NWS National Hurricane Center Miami FL EP102025
200 PM PDT Tue Aug 26 2025

...JULIETTE FORECAST TO WEAKEN OVER THE NEXT COUPLE DAYS...


SUMMARY OF 200 PM PDT...2100 UTC...INFORMATION
----------------------------------------------
LOCATION...19.9N 117.2W
ABOUT 410 MI...660 KM WNW OF SOCORRO ISLAND
ABOUT 515 MI...825 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 10 MPH...17 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES




Tropical Storm Juliette Discussion Number 9
NWS National Hurricane Center Miami FL EP102025
200 PM PDT Tue Aug 26 2025

The center of Juliette appears to be near the northern edge of the
central convective area, as there could still be some moderate
northeasterly shear affecting the cyclone. Overall, the structure
appears similar to, but slightly degraded compared to, the system's
appearance on satellite imagery 6 h ago. The latest objective
intensity estimates have been running in the 45-50 kt range, and the
latest Final-T numbers from TAFB and SAB are both 3.5 (55 kt). The
initial intensity is set at 55 kt for this advisory.

Although vertical wind shear over Juliette is forecast to be very
low for the next 24-30 h, the cyclone is expected to cross the 26C
sea-surface temperature (SST) isotherm by hour 12, and water
temperatures will continue to decrease with time along its path.
Juliette will also be moving into a progressively drier and more
stable airmass. Little change in strength is expected over the next
12-24 h, but steady weakening is expected when the cyclone moves
over colder water and through drier air. The NHC intensity forecast
is near the higher end of the guidance through 24 h, but lies in the
middle of the guidance envelope thereafter. Beyond 36 h,
southwesterly wind shear will increase as Juliette moves closer to
an upper-level trough located well to its northwest. The increasing
shear, along with the cold SSTs and dry air, should cause the
cyclone to lose its convection and become post-tropical in about 2
days. Global models show the remnant low gradually spinning down and
dissipating in 3 to 4 days.

Juliette's initial motion is estimated to be northwest, or 325/9 kt.
This general motion should continue over the next couple of days as
Juliette moves in between two strong mid-level ridges, one located
over northwestern Mexico and the other located well to the
west-northwest of the cyclone. Juliette should slow down some on
Wednesday as the steering currents weaken on the west side of the
mid-level ridge over northwestern Mexico. There has been a large
northeastward shift to the guidance this cycle. The latest official
forecast is in best agreement with the Google DeepMind ensemble
mean, but not nearly as far to the right as some of the other
consensus models like the TCVE and HCCA.


FORECAST POSITIONS AND MAX WINDS

INIT 26/2100Z 19.9N 117.2W 55 KT 65 MPH
12H 27/0600Z 21.0N 118.4W 55 KT 65 MPH
24H 27/1800Z 22.7N 119.8W 50 KT 60 MPH
36H 28/0600Z 24.2N 120.7W 40 KT 45 MPH
48H 28/1800Z 25.2N 121.2W 30 KT 35 MPH...POST-TROP/REMNT LOW
60H 29/0600Z 26.0N 121.6W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 29/1800Z 26.5N 121.9W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 30/1800Z...DISSIPATED

$$
Forecaster Hagen

[cycloneye]

BULLETIN
Tropical Storm Juliette Advisory Number 10
NWS National Hurricane Center Miami FL EP102025
800 PM PDT Tue Aug 26 2025

...JULIETTE LIKELY TO COMMENCE WEAKENING SOON...


SUMMARY OF 800 PM PDT...0300 UTC...INFORMATION
----------------------------------------------
LOCATION...20.9N 118.1W
ABOUT 545 MI...875 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA
MAXIMUM SUSTAINED WINDS...65 MPH...100 KM/H
PRESENT MOVEMENT...NW OR 325 DEGREES AT 12 MPH...19 KM/H
MINIMUM CENTRAL PRESSURE...996 MB...29.42 INCHES





Tropical Storm Juliette Discussion Number 10
NWS National Hurricane Center Miami FL EP102025
800 PM PDT Tue Aug 26 2025

Juliette has changed little in organization since earlier today,
but the overall coverage and intensity of deep convection has
decreased. Most of the strongest thunderstorm activity is occurring
in a small cluster just to the southeast of the estimated center.
Convective banding features are not particularly well-defined. The
advisory intensity is held at 55 kt in agreement with Dvorak
classifications of 3.5/3.5 from both TAFB and SAB and an objective
DPRINT intensity estimate from UW-CIMSS.

The storm continues on its northwestward trek with a motion estimate
of about 325/10 kt. Juliette is moving on the western periphery of
a mid-level high pressure system centered over northern Mexico.
This steering regime should continue through tomorrow. In 48 hours,
the cyclone should weaken and move more slowly in the low-level
flow. The official track forecast is somewhat to the right of the
previous one, but not as far to the right as the latest dynamical
model consensus.

Juliette is currently crossing a strong gradient of SSTs and is
headed for much cooler waters. This, along with drier low- to
mid-level air and increasing west-southwesterly vertical wind shear
should cause weakening. The official intensity forecast is very
close to the DSHIPS, LGEM, and HCCA numerical guidance. Given the
expected future environment, the tropical cyclone could weaken even
faster then indicated here.

Mid- to upper-level moisture associated with Juliette or its
remnants will probably spread over portions of northwestern Mexico
and the southwestern U.S. during the next few days.


FORECAST POSITIONS AND MAX WINDS

INIT 27/0300Z 20.9N 118.1W 55 KT 65 MPH
12H 27/1200Z 22.3N 119.3W 50 KT 60 MPH
24H 28/0000Z 24.0N 120.3W 45 KT 50 MPH
36H 28/1200Z 25.4N 120.9W 35 KT 40 MPH
48H 29/0000Z 26.2N 121.2W 25 KT 30 MPH...POST-TROP/REMNT LOW
60H 29/1200Z 26.8N 121.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 30/0000Z 27.4N 121.8W 20 KT 25 MPH...POST-TROP/REMNT LOW
96H 31/0000Z...DISSIPATED

$$
Forecaster Pasch