CPAC: ULIKA - Post-Tropical

Moderator: S2k Moderators

Message
Author
hurricanes1234
Category 5
Category 5
Posts: 2701
Joined: Sat Jul 28, 2012 6:19 pm
Location: Southern Caribbean

Re: EPAC: ULIKA - Tropical Storm

#41 Postby hurricanes1234 » Wed Sep 28, 2016 4:46 am

Amazing little hurricane. :ggreen: :ggreen:
0 likes   
PLEASE NOTE: With the exception of information from weather agencies that I may copy and paste here, my posts will NEVER be official, since I am NOT a meteorologist. They are solely my amateur opinion, and may or may not be accurate. Therefore, please DO NOT use them as official details, particularly when making important decisions. Thank you.

User avatar
Yellow Evan
Category 5
Category 5
Posts: 11261
Age: 20
Joined: Fri Jul 15, 2011 12:48 pm
Location: Henderson, Nevada/Norman, Oklahoma
Contact:

Re: EPAC: ULIKA - Hurricane

#42 Postby Yellow Evan » Wed Sep 28, 2016 8:22 am

Seems to be leveling off.
0 likes   

hurricanes1234
Category 5
Category 5
Posts: 2701
Joined: Sat Jul 28, 2012 6:19 pm
Location: Southern Caribbean

Re: EPAC: ULIKA - Tropical Storm

#43 Postby hurricanes1234 » Wed Sep 28, 2016 2:42 pm

No longer a hurricane. :( :( :(

Ulika was maintaining a small central dense overcast (CDO), with the
center well embedded within this convective mass overnight. Since
then, the cloud pattern has undergone considerable degradation. The
CDO has become much less distinct, to the point that it has no
longer become discernible. The deep convection in the former CDO
has also decreased in coverage and cloud top temperatures have
warmed substantially. TAFB and SAB provided a satellite
classifications of T4.0 and T2.5 at 1200 UTC, respectively. Since
that time, the cyclone's cloud pattern has further degraded, and the
initial intensity is lowered to a possibly generous 60 kt.

Ulika's environment already appears to have become much less
favorable. West-southwesterly to southwesterly shear is only likely
to increase as the cyclone gains latitude during the next couple of
days. In fact, the SHIPS model output indicates more than 30 kt of
shear by 36 hours. This, combined with a marginally moist
environment and an increasingly convergent flow aloft, means that
steady weakening is most likely. Global models show Ulika being
sheared apart in about 2 days, with the mid-level center racing
northeastward away from the low-level center. Rapid weakening
should occur by then, if it has not begun already, and remnant low
status is forecast in 72 hours. The new intensity forecast is
lowered relative to the previous one, and is near or below the
multi-model consensus.

The initial motion is 030/06. Ulika should turn northward soon,
as it rotates around a nearly stationary mid-tropospheric low seen
in water vapor imagery around 17N 143W. Once the system decouples
fully, the shallower cyclone's motion will be governed by the
low-level trade wind flow and turn westward with an increase in
forward speed. The new track forecast is a little to the right of
the previous one through 24 hours and then is very similar, with
the new forecast close to the multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 28/1500Z 14.5N 138.7W 60 KT 70 MPH
12H 29/0000Z 15.3N 138.6W 55 KT 65 MPH
24H 29/1200Z 16.0N 139.2W 50 KT 60 MPH
36H 30/0000Z 16.7N 140.1W 45 KT 50 MPH
48H 30/1200Z 17.3N 141.2W 35 KT 40 MPH
72H 01/1200Z 17.5N 144.1W 30 KT 35 MPH...POST-TROP/REMNT LOW
96H 02/1200Z 17.5N 148.6W 20 KT 25 MPH...POST-TROP/REMNT LOW
120H 03/1200Z...DISSIPATED

$$
Forecaster Kimberlain
0 likes   
PLEASE NOTE: With the exception of information from weather agencies that I may copy and paste here, my posts will NEVER be official, since I am NOT a meteorologist. They are solely my amateur opinion, and may or may not be accurate. Therefore, please DO NOT use them as official details, particularly when making important decisions. Thank you.

hurricanes1234
Category 5
Category 5
Posts: 2701
Joined: Sat Jul 28, 2012 6:19 pm
Location: Southern Caribbean

Re: EPAC: ULIKA - Tropical Storm

#44 Postby hurricanes1234 » Wed Sep 28, 2016 4:09 pm

Down to 50 knots. :cry:

However, I'm very happy it got the brief window to strengthen into a miniature little hurricane.
:sun: :sun:

000
WTPZ44 KNHC 282031
TCDEP4

TROPICAL STORM ULIKA DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL EP192016
200 PM PDT WED SEP 28 2016

Ulika's cloud pattern consists of a small area of deep convection
near the estimated center, with limited or no banding features.
The current intensity estimate has been reduced to 50 kt which is a
blend of Dvorak estimates from TAFB and SAB. Vertical shear,
mainly due to westerly upper-level flow associated with a broad
trough over the east-central Pacific, is predicted by the global
models to increase substantially over the next couple of days.
This, along with dry mid-tropospheric air, should cause steady
weakening and Ulika is likely to degenerate into a post-tropical
remnant low in 48 hours or less.

Ulika is turning gradually to the left, and the initial motion is
now estimated to be 010/6. As long as it maintains some vertical
depth, the small circulation of the tropical cyclone should
continue to rotate counter-clockwise around a mid-level low to its
west. Assuming that the system becomes a shallow cyclone in 36 to
48 hours, it should move generally westward in the low-level flow
by that time. The official forecast is very similar to the
previous one and lies between the latest GFS and ECMWF predictions.

FORECAST POSITIONS AND MAX WINDS

INIT 28/2100Z 15.1N 138.7W 50 KT 60 MPH
12H 29/0600Z 16.0N 138.9W 40 KT 45 MPH
24H 29/1800Z 16.9N 139.4W 35 KT 40 MPH
36H 30/0600Z 17.4N 140.2W 30 KT 35 MPH
48H 30/1800Z 17.6N 141.2W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 01/1800Z 17.7N 144.5W 15 KT 15 MPH...POST-TROP/REMNT LOW
96H 02/1800Z...DISSIPATED

$$
Forecaster Pasch/Kimberlain
0 likes   
PLEASE NOTE: With the exception of information from weather agencies that I may copy and paste here, my posts will NEVER be official, since I am NOT a meteorologist. They are solely my amateur opinion, and may or may not be accurate. Therefore, please DO NOT use them as official details, particularly when making important decisions. Thank you.

User avatar
Kingarabian
S2K Supporter
S2K Supporter
Posts: 9784
Joined: Sat Aug 08, 2009 3:06 am
Location: Honolulu, Hawaii

Re: EPAC: ULIKA - Tropical Storm

#45 Postby Kingarabian » Wed Sep 28, 2016 7:25 pm

18z GFS keeps it around for a while lol.
0 likes   
Image

User avatar
cycloneye
Storm2k Moderator
Storm2k Moderator
Posts: 114715
Age: 62
Joined: Thu Oct 10, 2002 10:54 am
Location: San Juan, Puerto Rico

Re: CPAC: ULIKA - Tropical Storm

#46 Postby cycloneye » Thu Sep 29, 2016 10:35 am

TROPICAL STORM ULIKA DISCUSSION NUMBER 13
NWS NATIONAL HURRICANE CENTER MIAMI FL EP192016
800 AM PDT THU SEP 29 2016

Ulika's cloud pattern continues to have a sheared appearance this
morning, with only a small area of bursting deep convection to the
east of the estimated low-level center location. The initial
intensity is set at 40 kt, which is a blend of Dvorak estimates from
SAB and TAFB. A very hostile dynamic environment lies ahead of
Ulika, with westerly shear forecast to increase to 40-50 kt in 36
hours. Given such unfavorable conditions, the system should
degenerate into a remnant low by the weekend, or sooner.

The cyclone has turned toward the northwest, and the initial motion
is estimated to be around 320/6 kt. The flow on the southern side
of a weak low- to mid-level ridge should cause Ulika to turn toward
the west-northwest and then west over the next couple of days. The
official track forecast is between the latest GFS and ECMWF tracks
and only a little bit north of the previous NHC forecast.

The next advisory on Ulika will be issued by the Central Pacific
Hurricane Center.

FORECAST POSITIONS AND MAX WINDS

INIT 29/1500Z 16.7N 139.7W 40 KT 45 MPH
12H 30/0000Z 17.3N 140.4W 35 KT 40 MPH
24H 30/1200Z 17.8N 141.8W 30 KT 35 MPH
36H 01/0000Z 18.0N 143.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 01/1200Z 18.0N 145.0W 25 KT 30 MPH...POST-TROP/REMNT LOW
72H 02/1200Z...DISSIPATED

$$
Forecaster Pasch
0 likes   
Visit the Caribbean-Central America Weather Thread where you can find at first post web cams,radars
and observations from Caribbean basin members Click Here

User avatar
cycloneye
Storm2k Moderator
Storm2k Moderator
Posts: 114715
Age: 62
Joined: Thu Oct 10, 2002 10:54 am
Location: San Juan, Puerto Rico

Re: CPAC: ULIKA - Tropical Storm

#47 Postby cycloneye » Thu Sep 29, 2016 4:18 pm

TROPICAL STORM ULIKA DISCUSSION NUMBER 14
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP192016
1100 AM HST THU SEP 29 2016

After a burst of deep convection that persisted near the
center of Ulika for most of the night, visible satellite imagery
indicates that the low-level circulation center of Ulika is now
exposed to the southwest of an area of waning deep convection.
Meanwhile, water vapor imagery shows that Ulika is embedded in a
hostile environment aloft, with a mid-level low centered to its
northwest supplying over 30 kt of vertical wind shear. A
conservative blend of the subjective Dvorak current intensity
estimates of 1.5/25 kt from GTW, 2.0/30 kt from HFO and SAB, and the
ADT estimate of 2.9/43 kt from UW-CIMSS yielded an initial intensity
estimate of 35 kt for this cycle. This was subsequently confirmed by
an 1858Z ASCAT pass that detected 35 kt in the north and northeast
semicircles.

The initial motion estimate for this advisory is 305/07 kt, with
Ulika being steered toward the northwest by the flow around the
nearby mid-level low. This feature will likely prohibit deep
convection from re-developing over the center as associated shear is
forecast to steadily increase to near 60 kt over the next 2 days.
This will cause the cyclone to become increasingly shallow over the
next 12 to 24 hours, with spin-down to a remnant low expected to
occur soon. The shallow cyclone is then forecast to move toward the
west (until dissipation occurs) within the low-level trade wind flow
supported by a surface high far to the north. The updated official
track forecast parallels the previous, but is shifted to the right
and moves the cyclone at a greater forward speed, in line with
observed trends, and the latest GFS and ECMWF guidance. The updated
intensity forecast closely follows the previous and SHIPS/LGEM
guidance, but is not as aggressive in anticipating dissipation,
which SHIPS indicates will occur within 36 hours.


FORECAST POSITIONS AND MAX WINDS

INIT 29/2100Z 17.2N 140.2W 35 KT 40 MPH
12H 30/0600Z 17.7N 141.2W 30 KT 35 MPH
24H 30/1800Z 18.3N 142.9W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 01/0600Z 18.4N 144.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 01/1800Z 18.2N 147.6W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 02/1800Z...DISSIPATED

$$
Forecaster Birchard
0 likes   
Visit the Caribbean-Central America Weather Thread where you can find at first post web cams,radars
and observations from Caribbean basin members Click Here

hurricanes1234
Category 5
Category 5
Posts: 2701
Joined: Sat Jul 28, 2012 6:19 pm
Location: Southern Caribbean

Re: CPAC: ULIKA - Tropical Storm

#48 Postby hurricanes1234 » Thu Sep 29, 2016 10:09 pm

WTPA42 PHFO 300239
TCDCP2

TROPICAL STORM ULIKA DISCUSSION NUMBER 15
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP192016
500 PM HST THU SEP 29 2016

The well-defined low-level circulation center of Ulika has been
exposed to the south and southwest of limited deep convection for
most of the time since the previous advisory, but modest new
convection has more recently developed close to the center, despite
strong westerly shear on the order of 30-40 kt. Subjective Dvorak
current intensity estimates have been trending lower, and range from
too weak to classify from SAB to 1.5/25 kt from HFO/GTW, while ADT
has diminished to 2.2/32 kt. The initial intensity of 35 kt used for
this advisory is primarily based on a pair of mid-morning ASCAT
passes that indicated winds of at least 35 kt, and the fact that the
satellite presentation has changed little since.

The initial motion estimate for this advisory is 305/09 kt, with
Ulika being steered toward the northwest by the counter-
clockwise flow around a mid-level low centered to the northwest.
Although isolated small thunderstorm cells have briefly developed
near the center of Ulika this afternoon, persistent deep convection
is not expected over the center as shear is forecast to further
increase the next 2 days. The cyclone is therefore expected to
become increasingly shallow over the next 12 to 24 hours, and
spin-down to a remnant low is expected to occur soon.

As the system weakens, the primary steering mechanism will become a
surface high far to the north, which will drive the system toward
the west until dissipation occurs. The official track forecast
closely follows the previous, and most closely follows the GFEX
model blend. Trends presented by SHIPS/LGEM were closely followed
for the intensity forecast, while HWFI/GHMI (and therefore IVCN)
were disregarded due to an unrealistic intensification trend
indicated on days 2 and 3.


FORECAST POSITIONS AND MAX WINDS

INIT 30/0300Z 17.7N 141.0W 35 KT 40 MPH
12H 30/1200Z 18.3N 142.3W 30 KT 35 MPH
24H 01/0000Z 18.6N 144.3W 25 KT 30 MPH...POST-TROP/REMNT LOW
36H 01/1200Z 18.6N 146.4W 25 KT 30 MPH...POST-TROP/REMNT LOW
48H 02/0000Z 18.6N 149.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
72H 03/0000Z...DISSIPATED

$$
Forecaster Birchard
0 likes   
PLEASE NOTE: With the exception of information from weather agencies that I may copy and paste here, my posts will NEVER be official, since I am NOT a meteorologist. They are solely my amateur opinion, and may or may not be accurate. Therefore, please DO NOT use them as official details, particularly when making important decisions. Thank you.

hurricanes1234
Category 5
Category 5
Posts: 2701
Joined: Sat Jul 28, 2012 6:19 pm
Location: Southern Caribbean

Re: CPAC: ULIKA - Tropical Depression

#49 Postby hurricanes1234 » Fri Sep 30, 2016 4:53 am

WTPA42 PHFO 300834
TCDCP2

TROPICAL DEPRESSION ULIKA DISCUSSION NUMBER 16
NWS CENTRAL PACIFIC HURRICANE CENTER HONOLULU HI EP192016
1100 PM HST THU SEP 29 2016

The last significant deep convection around Ulika dissipated this
morning. Only a low-level circulation center now remains. The
subjective Dvorak current intensity estimate from HFO was 1.0/25
kt while JTWC analyzed Ulika as too weak to classify. A 30/0630 UTC
ASCAT pass just west of Ulika showed maximum winds of 30 kt. I
have dropped the initial intensity to 30 kt for this advisory, so
Ulika has now weakened to a tropical depression.

The initial motion estimate for this advisory is 290/08 kt. Ulika
is expected to remain a shallow system steered by a ridge to the
northwest in the lower troposphere. There is a trough aloft to the
north of the system with a westerly jet stream along 20N. The strong
west winds aloft will help create strong vertical wind shear over
Ulika and prevent re-intensification. The official track forecast
closely follows the previous one. The intensity forecast continues
to closely follow SHIPS/LGEM. Ulika is expected to become a remnant
low on Friday and to dissipate by Saturday night.


FORECAST POSITIONS AND MAX WINDS

INIT 30/0900Z 18.0N 141.7W 30 KT 35 MPH
12H 30/1800Z 18.5N 142.8W 25 KT 30 MPH...POST-TROP/REMNT LOW
24H 01/0600Z 18.5N 145.0W 20 KT 25 MPH...POST-TROP/REMNT LOW
36H 01/1800Z 18.5N 147.5W 20 KT 25 MPH...POST-TROP/REMNT LOW
48H 02/0600Z...DISSIPATED

$$
Forecaster Donaldson
0 likes   
PLEASE NOTE: With the exception of information from weather agencies that I may copy and paste here, my posts will NEVER be official, since I am NOT a meteorologist. They are solely my amateur opinion, and may or may not be accurate. Therefore, please DO NOT use them as official details, particularly when making important decisions. Thank you.


Return to “2016”

Who is online

Users browsing this forum: No registered users and 1 guest