EPAC: SERGIO - Remnants

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Re: EPAC: SERGIO - Hurricane

#81 Postby 1900hurricane » Thu Oct 04, 2018 5:37 pm

That's a pretty large eye emerging.
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Re: EPAC: SERGIO - Hurricane

#82 Postby mrbagyo » Thu Oct 04, 2018 6:07 pm

Goin Annular?
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Re: EPAC: SERGIO - Hurricane

#83 Postby Kingarabian » Thu Oct 04, 2018 6:54 pm

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Re: EPAC: SERGIO - Hurricane

#84 Postby Kingarabian » Thu Oct 04, 2018 6:55 pm

mrbagyo wrote:Goin Annular?


There's still a heavy feeder band
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Re: EPAC: SERGIO - Hurricane

#85 Postby Ntxw » Thu Oct 04, 2018 7:15 pm

Storm has become very photogenic of late. Shear still looks low the next couple of days with ample warm water. It will be until day 5 that some cooler waters than current may effect some but conditions still look decent. Will be around for awhile longer.

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Re: EPAC: SERGIO - Hurricane

#86 Postby Kingarabian » Thu Oct 04, 2018 7:20 pm

And the GFS continues to show its true peak within 72 hours.
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Re: EPAC: SERGIO - Hurricane

#87 Postby mrbagyo » Thu Oct 04, 2018 7:50 pm

Kingarabian wrote:
mrbagyo wrote:Goin Annular?


There's still a heavy feeder band


Yep I know, but I think it could go in that direction (once it eliminated the said feeder band).
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Re: EPAC: SERGIO - Hurricane

#88 Postby cycloneye » Thu Oct 04, 2018 9:39 pm

Hurricane Sergio Discussion Number 23
NWS National Hurricane Center Miami FL EP212018
800 PM PDT Thu Oct 04 2018

Sergio's cloud pattern has deteriorated somewhat since the previous
advisory, with cloud tops warming and the eye becoming more ragged
and less distinct. The initial intensity is reduced to 110 kt based
on a blend of the latest objective and subjective Dvorak estimates.
Sergio is expected to steadily weaken for the next 48 hours while
moving into a drier and more stable environment. By then, most of
the guidance suggests little change from 48-72 hours before the
shear increases by the end of the period and SSTs cool to between
26C and 27C, which should again result in weakening. The new NHC
intensity forecast is lower than the previous one during the first
48 hours to account for the observed weakening and the trend in the
guidance, but is similar after that time. This prediction is close
to or a bit above the latest HCCA intensity consensus aid.

Sergio has turned toward the left during the past few hours, with an
initial motion estimate now 305/07. A mid-level ridge building to
the northwest of Sergio will steer the hurricane toward the west and
even toward the west-southwest during the next 36 to 48 hours. After
that time, an amplifying longwave trough over western North America
will erode the ridge and cause Sergio to recurve, with a faster
northeastward motion shown by day 5. The new NHC track forecast has
been adjusted to the south of the previous one from 24 to 48 hours,
following the trend of the latest consensus aids, which are showing
a more equatorward motion during this time. At days 3 through 5, the
NHC track is largely an update of the previous one, and lies between
the faster GFS and the slower ECMWF models.

FORECAST POSITIONS AND MAX WINDS

INIT 05/0300Z 15.9N 120.5W 110 KT 125 MPH
12H 05/1200Z 16.0N 121.4W 100 KT 115 MPH
24H 06/0000Z 15.9N 122.5W 95 KT 110 MPH
36H 06/1200Z 15.6N 123.8W 85 KT 100 MPH
48H 07/0000Z 15.5N 125.0W 80 KT 90 MPH
72H 08/0000Z 16.0N 127.0W 80 KT 90 MPH
96H 09/0000Z 17.5N 127.0W 70 KT 80 MPH
120H 10/0000Z 19.5N 124.5W 65 KT 75 MPH

$$
Forecaster Brennan
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Re: EPAC: SERGIO - Hurricane

#89 Postby cycloneye » Fri Oct 05, 2018 4:56 am

Hurricane Sergio Discussion Number 24
NWS National Hurricane Center Miami FL EP212018
200 AM PDT Fri Oct 05 2018

Sergio's eye has cooled somewhat during the past few hours, but
there have been no significant changes to the surrounding deep
convection. Despite that observation, all available intensity
estimates have fallen to between 100-105 kt, and the advisory
intensity is therefore set at 105 kt. The gradual weakening trend
Sergio has been on is expected to continue for the duration of the
forecast period as the hurricane moves toward slightly cooler
waters and into a drier, more stable environment. An increase in
shear by days 4 and 5 should also help the weakening process along.
The updated NHC intensity forecast is not too different from the
previous one and is close to the intensity consensus, HCCA, and
Florida State Superensemble.

Sergio has continued to turn to the left and is now moving
west-northwestward, or 290/7 kt. Northerly flow behind a mid-level
trough that will swing across the Baja California peninsula will
likely push Sergio west-southwestward by 24 hours, and the NHC
forecast continues to reflect that scenario. After 48 hours, a
break in the ridge left behind by the trough should allow Sergio
to turn toward the north by days 3-4. Another shortwave trough is
then expected to cause a northeastward acceleration by the end of
the forecast period. The GFS and ECMWF, along with the other
major track models, have come into better agreement on this
acceleration by day 5, and the new official forecast is therefore a
little faster than the previous one at that time.


FORECAST POSITIONS AND MAX WINDS

INIT 05/0900Z 16.0N 121.2W 105 KT 120 MPH
12H 05/1800Z 16.0N 122.0W 95 KT 110 MPH
24H 06/0600Z 15.7N 123.1W 90 KT 105 MPH
36H 06/1800Z 15.5N 124.3W 85 KT 100 MPH
48H 07/0600Z 15.4N 125.5W 80 KT 90 MPH
72H 08/0600Z 16.3N 126.9W 80 KT 90 MPH
96H 09/0600Z 18.0N 126.0W 70 KT 80 MPH
120H 10/0600Z 20.5N 122.5W 65 KT 75 MPH

$$
Forecaster Berg
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Re: EPAC: SERGIO - Hurricane

#90 Postby cycloneye » Fri Oct 05, 2018 9:55 am

Hurricane Sergio Discussion Number 24
NWS National Hurricane Center Miami FL EP212018
200 AM PDT Fri Oct 05 2018

Sergio's eye has cooled somewhat during the past few hours, but
there have been no significant changes to the surrounding deep
convection. Despite that observation, all available intensity
estimates have fallen to between 100-105 kt, and the advisory
intensity is therefore set at 105 kt. The gradual weakening trend
Sergio has been on is expected to continue for the duration of the
forecast period as the hurricane moves toward slightly cooler
waters and into a drier, more stable environment. An increase in
shear by days 4 and 5 should also help the weakening process along.
The updated NHC intensity forecast is not too different from the
previous one and is close to the intensity consensus, HCCA, and
Florida State Superensemble.

Sergio has continued to turn to the left and is now moving
west-northwestward, or 290/7 kt. Northerly flow behind a mid-level
trough that will swing across the Baja California peninsula will
likely push Sergio west-southwestward by 24 hours, and the NHC
forecast continues to reflect that scenario. After 48 hours, a
break in the ridge left behind by the trough should allow Sergio
to turn toward the north by days 3-4. Another shortwave trough is
then expected to cause a northeastward acceleration by the end of
the forecast period. The GFS and ECMWF, along with the other
major track models, have come into better agreement on this
acceleration by day 5, and the new official forecast is therefore a
little faster than the previous one at that time.


FORECAST POSITIONS AND MAX WINDS

INIT 05/0900Z 16.0N 121.2W 105 KT 120 MPH
12H 05/1800Z 16.0N 122.0W 95 KT 110 MPH
24H 06/0600Z 15.7N 123.1W 90 KT 105 MPH
36H 06/1800Z 15.5N 124.3W 85 KT 100 MPH
48H 07/0600Z 15.4N 125.5W 80 KT 90 MPH
72H 08/0600Z 16.3N 126.9W 80 KT 90 MPH
96H 09/0600Z 18.0N 126.0W 70 KT 80 MPH
120H 10/0600Z 20.5N 122.5W 65 KT 75 MPH

$$
Forecaster Berg
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Re: EPAC: SERGIO - Hurricane

#91 Postby TorSkk » Fri Oct 05, 2018 10:02 am

Hurricane Sergio Discussion Number 25
NWS National Hurricane Center Miami FL EP212018
800 AM PDT Fri Oct 05 2018

GOES-16 images and a 1054 UTC ATMS microwave overpass indicate
that Sergio's 25 n mi eye has become a bit ragged this morning, and
has continued to cool. Despite the eye's irregularity, the inner
core convection is still intact and is producing very cold (-76C)
cloud tops. Primarily due to the eye adjustment temperature,
however, the subjective and objective satellite intensity estimates,
as well as a recent SATCON analysis, have again decreased to 95-100
kt, and the initial intensity is subsequently lowered to 100 kt.

Although due to the possibility of unpredicted inner core structure
changes in the short term which could cause Sergio to strengthen
again, the current weakening trend is expected to continue through
day 5 as Sergio moves toward decreasing oceanic temperatures and
into a stabilizing surrounding atmosphere. The statistical
intensity guidance as well as the large-scale models show increasing
southwesterly shear entering the picture after 72 hours. This
should also aid in the forecast weakening trend. The official
forecast is just an update of the previous one and follows the
NOAA-HCCA consensus and is just above the Florida State
Superensemble.

Sergio is moving a little left of the previous 6-hr motion...now
westward, or 280/7 kt. A gradual turn toward the west-southwest
during the next 36 hours is expected as high pressure located
north-northeast of the Hawaiian Islands builds to the north of
Sergio. Over the weekend, a decrease in forward speed and a turn
toward the northwest is forecast as the aforementioned mid-level
high retrogrades in response to an amplifying trough over the
southwestern United States and Baja California peninsula. Beyond the
72 hour period, increasing southwesterly mid-tropospheric flow
should induce a northeastward accelerated motion through the
remaining portion of the forecast. The NHC forecast is adjusted a
little toward the south of the last advisory through 72 hours to
agree more with the various consensus models, but is quite similar
in motion and forward speed beyond that period.


FORECAST POSITIONS AND MAX WINDS

INIT 05/1500Z 15.9N 121.8W 100 KT 115 MPH
12H 06/0000Z 15.8N 122.7W 95 KT 110 MPH
24H 06/1200Z 15.5N 123.8W 90 KT 105 MPH
36H 07/0000Z 15.2N 125.0W 85 KT 100 MPH
48H 07/1200Z 15.3N 126.0W 85 KT 100 MPH
72H 08/1200Z 16.5N 126.8W 80 KT 90 MPH
96H 09/1200Z 18.5N 125.0W 70 KT 80 MPH
120H 10/1200Z 21.5N 120.8W 60 KT 70 MPH

$$
Forecaster Roberts
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Re: EPAC: SERGIO - Hurricane

#92 Postby Kingarabian » Fri Oct 05, 2018 2:33 pm

Hints that a transition towards annular status is now beginning:

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Re: EPAC: SERGIO - Hurricane

#93 Postby cycloneye » Fri Oct 05, 2018 3:45 pm

Hurricane Sergio Discussion Number 26
NWS National Hurricane Center Miami FL EP212018
200 PM PDT Fri Oct 05 2018

This afternoon's satellite presentation shows that Sergio has become
a little better organized. Eyewall cloud temperatures have once
again cooled, and the ragged, cloud-filled eye has warmed during the
past 6 hours. Accordingly, the subjective and objective T-numbers
support increasing the initial intensity to 105 kt for this
advisory.

As mentioned in this morning's discussion, unforeseen short term
inner-core structure changes could cause some intensity
fluctuations. Since the environment is forecast to remain favorable
during the next 24 hours or so, little change in strength is
forecast, and again, the cyclone could become a little stronger than
reflected in the forecast. Beyond this period, gradual weakening is
expected through day 5 as Sergio moves toward decreasing sea-surface
temperatures and into a more stable surrounding environment. The
Decay-SHIPS and LGEM intensity guidance, as well as the large-scale
models, show increasing southwesterly shear disrupting Sergio's
outflow pattern after 72 hours. The intensity forecast is similar
to the previous package, and is just above the NOAA-HCCA and IVCN
consensus models and below the statistical intensity aids.

Sergio's motion is estimated to be west-southwestward, or 250/6 kt
within the mid-level steering flow produced by a building high
pressure system located north-northeast of the Hawaiian Islands. By
early next week, a decrease in forward speed and a turn toward the
northwest to north-northwest is forecast as the aforementioned
mid-level high retrogrades in response to an amplifying trough over
the southwestern United States and Baja California peninsula. Beyond
day 3, increasing southwesterly mid-tropospheric flow should induce
a northeastward accelerated motion through day 5. The NHC forecast
is again adjusted south of the last advisory through 48 hours, and
is close to the various multi-model consensus guidance.

FORECAST POSITIONS AND MAX WINDS

INIT 05/2100Z 15.7N 122.3W 105 KT 120 MPH
12H 06/0600Z 15.3N 123.1W 105 KT 120 MPH
24H 06/1800Z 14.9N 124.3W 100 KT 115 MPH
36H 07/0600Z 14.8N 125.4W 100 KT 115 MPH
48H 07/1800Z 15.1N 126.3W 90 KT 105 MPH
72H 08/1800Z 16.7N 126.5W 80 KT 90 MPH
96H 09/1800Z 18.9N 123.9W 70 KT 80 MPH
120H 10/1800Z 22.0N 119.3W 65 KT 75 MPH

$$
Forecaster Roberts
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Re: EPAC: SERGIO - Hurricane

#94 Postby Ntxw » Fri Oct 05, 2018 4:23 pm

Starting to take on some annular characteristics. Moving into warmer SSTs and low shear for a day or two. ACE about 20 so far another 10-15 to go at least.

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Re: EPAC: SERGIO - Hurricane

#95 Postby cycloneye » Fri Oct 05, 2018 9:38 pm

Hurricane Sergio Discussion Number 27
NWS National Hurricane Center Miami FL EP212018
800 PM PDT Fri Oct 05 2018

Sergio has maintained a 25-30-nmi wide eye this evening, and a ring
of cold cloud tops has cooled around the well-defined eye. Satellite
intensity estimates range from T5.5/102 kt from TAFB and SAB to
T5.9/122 kt from ADT and a T6.0/115 kt NHC objective T-number, so
the intensity has been bumped up to 110 kt for this advisory.
Upper-level outflow and the overall convective pattern have both
improved since the previous advisory while Sergio has lost latitude
and moved over warmer waters.

The motion is now southwestward, or 235/06 kt. Sergio's recent
southwestward motion is forecast to be short lived, with a return to
a west-southwestward to westward motion expected within the next 12
hours. The deep-layer ridge to the north of Sergio is forecast to
become more narrow due to a passing shortwave trough, but it is
basically expected to remain intact. This feature will steer the
hurricane slowly westward through Sunday. By Monday, however, a
stronger trough is forecast by the global models to drop southward
off the coasts of California and Baja California, causing a
significant weakening and erosion of the western portion of the
ridge. This is expected to result in Sergio turning slowly
northeastward on Monday, and accelerate on days 4 and 5. The new NHC
forecast track is similar to the previous advisory track, and lies
close to consensus models TVCE and NOAA-HCCA.

Other than very brief intrusions of dry mid-level air and possible
upwelling beneath the hurricane due to its slow forward speed, there
do not appear to be any other negative factors that would
significantly disrupt Sergio's intensity for the next 36-48 hours.
By 72 hours and beyond, however, increasing southwesterly vertical
wind shear is expected to induce a steady weakening trend after the
cyclone begins accelerating toward the northeast, and on days 4 and
5 passing over the cold wake left behind by former Hurricane Rosa.
The new official intensity forecast is similar to the previous one,
and is near an average of the NOAA-HCCA and IVCN consensus models.

FORECAST POSITIONS AND MAX WINDS

INIT 06/0300Z 15.3N 122.7W 110 KT 125 MPH
12H 06/1200Z 15.0N 123.6W 110 KT 125 MPH
24H 07/0000Z 14.7N 124.8W 105 KT 120 MPH
36H 07/1200Z 14.8N 125.8W 100 KT 115 MPH
48H 08/0000Z 15.4N 126.5W 95 KT 110 MPH
72H 09/0000Z 17.1N 126.0W 85 KT 100 MPH
96H 10/0000Z 19.4N 122.7W 70 KT 80 MPH
120H 11/0000Z 23.0N 118.0W 60 KT 70 MPH

$$
Forecaster Stewart
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Re: EPAC: SERGIO - Hurricane

#96 Postby cycloneye » Sat Oct 06, 2018 5:14 am

Hurricane Sergio Discussion Number 28
NWS National Hurricane Center Miami FL EP212018
200 AM PDT Sat Oct 06 2018

Sergio has changed little in structure since the last advisory. It
still has a 25-30 n mi wide eye surrounded by cold convective tops,
and with not much change in intensity estimates, the estimated
maximum winds remain 110 kt. Sergio's intensity is not likely to
change much during the next day or two, although some slight
weakening is possible as the hurricane's speed slows down and it
upwells some colder water from below, or due to possible internal
structural changes. More definitive weakening is anticipated by
days 4 and 5 due to an increase in westerly and southwesterly
shear and the hurricane reaching colder waters. The NHC intensity
forecast remains close to a blend of the ICON consensus and the HCCA
model. However, the statistical-dynamical models remain a bit
higher, and it is possible that Sergio won't lose quite as much
punch during the next several days as is indicated by the official
forecast.

Sergio continues to dive southwestward with an initial motion of
235/7 kt. A shortwave trough swinging across the Baja California
peninsula will bypass Sergio during the day, leaving a weakness in
the ridge that will allow the hurricane to begin making a sharp
northward and then northeastward turn during the next 24-72 hours.
Another shortwave trough forecast to dig southward off the
California coast will then cause Sergio to accelerate northeastward
on days 4 and 5. Notable changes in this forecast update include a
slightly wider turn from 24-72 hours, and more spread in the model
speeds once Sergio accelerates toward the Baja California
peninsula. As is usually the case in these scenarios, the ECMWF is
much slower than the other models, and because of that, the new NHC
forecast is a bit slower than the previous one, especially on day 5.


FORECAST POSITIONS AND MAX WINDS

INIT 06/0900Z 14.9N 123.5W 110 KT 125 MPH
12H 06/1800Z 14.6N 124.4W 105 KT 120 MPH
24H 07/0600Z 14.4N 125.6W 100 KT 115 MPH
36H 07/1800Z 14.7N 126.5W 95 KT 110 MPH
48H 08/0600Z 15.2N 127.0W 90 KT 105 MPH
72H 09/0600Z 16.9N 126.1W 80 KT 90 MPH
96H 10/0600Z 19.0N 123.0W 65 KT 75 MPH
120H 11/0600Z 23.0N 118.0W 55 KT 65 MPH

$$
Forecaster Berg
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Re: EPAC: SERGIO - Hurricane

#97 Postby cycloneye » Sat Oct 06, 2018 9:45 am

Hurricane Sergio Discussion Number 29
NWS National Hurricane Center Miami FL EP212018
800 AM PDT Sat Oct 06 2018

Sergio has remained nearly steady-state since last night and the
clear eye is still surrounded by very cold cloud tops. The initial
intensity remains 110 kt, based on a blend of subjective and
objective Dvorak intensity estimates. The primary moderating factor
for Sergio's intensity over the next few days will likely be sea
surface temperatures since GFS and ECMWF SHIPS diagnostics suggest
that the environment will be otherwise favorable. Sergio is now
moving west-southwestward at around 6 kt, likely just fast enough to
outrun its own cold wake. Little change in Sergio's intensity is
expected for the next day or so while the hurricane is forecast to
continue moving at around this same forward speed. By early next
week, a slower motion will likely cause some weakening to occur, as
Sergio becomes trapped over colder upwelled waters, with further
weakening likely when Sergio reaches much cooler waters to the
north. The ocean-coupled regional models show more weakening than
currently indicated by the official forecast, while DSHP and LGEM
show a stronger storm, probably in part because those models use a
constant ocean field. Confidence in the intensity forecast is not
very high, and it is likely that the faster Sergio moves, the
stronger it will be.

The global models are in fairly good agreement on the general track
of Sergio through the middle of next week, but they disagree on how
quickly Sergio will move along that path. Sergio is still forecast
to make a sharp u-turn toward the northeast over the next 3 days and
then accelerate in that direction between 72 and 120 h. Most of the
models are showing a slightly slower forward speed than earlier
cycles. However there are still large differences in their
representation of a shortwave trough off the coast of California
that will cause Sergio's acceleration, and the model spread remains
high. The new official track forecast is similar to the previous
advisory but generally shows a slower speed, especially after 48 h,
in line with the latest track consensus models.

FORECAST POSITIONS AND MAX WINDS

INIT 06/1500Z 14.7N 124.0W 110 KT 125 MPH
12H 07/0000Z 14.5N 125.0W 110 KT 125 MPH
24H 07/1200Z 14.5N 126.0W 105 KT 120 MPH
36H 08/0000Z 14.9N 126.8W 100 KT 115 MPH
48H 08/1200Z 15.5N 127.0W 90 KT 105 MPH
72H 09/1200Z 17.2N 125.6W 80 KT 90 MPH
96H 10/1200Z 19.5N 122.0W 70 KT 80 MPH
120H 11/1200Z 23.6N 117.0W 50 KT 60 MPH

$$
Forecaster Zelinsky
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Re: EPAC: SERGIO - Hurricane

#98 Postby cycloneye » Sat Oct 06, 2018 3:45 pm

Hurricane Sergio Discussion Number 30
NWS National Hurricane Center Miami FL EP212018
200 PM PDT Sat Oct 06 2018

There has been little change in Sergio's satellite presentation
today. The large eye remains well defined in visible and infrared
satellite imagery, but there has been a slight warming of the
surrounding cloud tops since this morning. However, the latest
subjective and objective satellite intensity estimates still support
an initial wind speed of 110 kt. As mentioned in the previous
discussion, the primary factor regarding Sergio's future intensity
will be ocean temperatures beneath the cyclone over the next few
days, since the other environmental conditions are expected to
remain favorable. Sergio should remain over warm waters during the
next day or so, but some upwelling of cooler water is possible as
Sergio slows down and makes its predicted sharp turn Sunday night
and Monday, and this is forecast to cause some gradual weakening
during that time. After 72 hours, cooler waters, increasing
southwesterly shear, and less favorable thermodynamic conditions are
likely to result in additional weakening. The NHC intensity
forecast lies between the higher statistical guidance and the
consensus aids, and is very similar to the previous advisory.

Sergio is moving west-southwestward at about 6 kt. The hurricane
should turn westward tonight before making a sharp northeastward
turn as a mid-level trough drops southward to the north of Sergio
and erodes the western portion of the ridge. By early next week,
Sergio should move northeastward ahead of the aforementioned trough.
The track guidance is in good agreement on the overall scenario but
there continues to be differences in the future forward speed of the
hurricane. The guidance has once again trended a little slower this
cycle, and the new NHC track lies between the previous forecast and
the latest consensus models.

FORECAST POSITIONS AND MAX WINDS

INIT 06/2100Z 14.6N 124.7W 110 KT 125 MPH
12H 07/0600Z 14.5N 125.7W 110 KT 125 MPH
24H 07/1800Z 14.6N 126.9W 105 KT 120 MPH
36H 08/0600Z 15.1N 127.4W 100 KT 115 MPH
48H 08/1800Z 15.7N 127.4W 90 KT 105 MPH
72H 09/1800Z 17.5N 125.6W 80 KT 90 MPH
96H 10/1800Z 20.0N 121.8W 70 KT 80 MPH
120H 11/1800Z 24.2N 116.5W 50 KT 60 MPH

$$
Forecaster Brown
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Re: EPAC: SERGIO - Hurricane

#99 Postby 1900hurricane » Sun Oct 07, 2018 9:13 am

The eye has emerged even larger now.

Image
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Re: EPAC: SERGIO - Hurricane

#100 Postby cycloneye » Sun Oct 07, 2018 9:44 am

Hurricane Sergio Discussion Number 33
NWS National Hurricane Center Miami FL EP212018
800 AM PDT Sun Oct 07 2018

Somewhat quickly and unexpectedly, Sergio took on the appearance of
an annular hurricane overnight. The eye of the hurricane expanded,
nearly doubling in size (now 70 n mi across), and most of the
banding features disappeared. However, IR imagery over the past
hour or two indicates that the hurricane is still somewhat
asymmetrical, suggesting that the hurricane may not have a classical
annular structure, at least not yet. The initial intensity has been
lowered to 90 kt, in agreement with the latest current intensity
estimates from TAFB and SAB.

The hurricane continues to move due west with an initial forward
speed of 7 kt. Sergio is still expected to slow down and turn first
northward, and then northeastward over the next couple of days. By
mid-week, a mid-level shortwave trough moving southward off coast of
California should cause Sergio to accelerate northeastward toward
the Baja California peninsula. The global models remain in fairly
good agreement on the track of the cyclone through the middle of
next week, and only small changes were made to the NHC track
forecast to move it closer to the model consensus.

As long as Sergio can maintain its annular-like structure, only slow
weakening is anticipated due to continued effects of ocean upwelling
combined with the slow forward motion of the hurricane. By the end
of the forecast period, Sergio will be moving over much cooler SSTs
located west of the Baja California peninsula, and a faster
weakening rate is forecast. Given the lower initial intensity of
Sergio, the official intensity forecast is a little lower for the
first two days of the forecast, but is very similar beyond that
time.


FORECAST POSITIONS AND MAX WINDS

INIT 07/1500Z 14.5N 126.8W 90 KT 105 MPH
12H 08/0000Z 14.8N 127.6W 85 KT 100 MPH
24H 08/1200Z 15.2N 128.2W 80 KT 90 MPH
36H 09/0000Z 15.9N 128.1W 75 KT 85 MPH
48H 09/1200Z 16.7N 127.3W 70 KT 80 MPH
72H 10/1200Z 18.8N 123.8W 65 KT 75 MPH
96H 11/1200Z 22.0N 119.5W 55 KT 65 MPH
120H 12/1200Z 26.5N 114.0W 45 KT 50 MPH

$$
Forecaster Zelinsky
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