EPAC: KARINA - Post-Tropical

[cycloneye]

HURRICANE KARINA DISCUSSION NUMBER 8
NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014
200 PM PDT THU AUG 14 2014

Despite moderate northeasterly vertical wind shear, Karina has
managed to develop a closed mid-level eye with a diameter of around
10-12 nmi since the previous advisory as noted in recent SSMI/S and
AMSU microwave imagery. Visible satellite imagery also indicates
that a cloud-filled eye has appeared in the middle of the nearly
circular CDO during past hour or so. Satellite intensity estimates
are a consensus T4.0/65 kt, and ADT estimates from UW-CIMSS ADT
have been steady at T4.4/75 kt for the past couple of hours. As a
result of these data, the intensity has been increased to 65 kt.

The initial motion estimate is 270/13 kt, which is based primarily
on passive microwave satellite position fixes. Karina's apparent
westward acceleration is likely due to the low-level center moving
or reforming underneath the well-defined mid-level eye. As a result,
this westward jog is expected to be a temporary motion, and Karina
should slow down somewhat in the near-term. Otherwise, the
hurricane is expected to remain on a basic westward track for the
next 4 days as Karina is steered by a deep-layer ridge to its north.
Afterwards, the cyclone is expected to slow down significantly and
make a turn toward the west-southwest or southwest as Karina begins
to interact with possible multiple tropical cyclones developing in
the central Pacific and eastern Pacific basins. As mentioned in the
previous discussion, rather than committing to any one particular
model solution this far out in time, the NHC track forecast instead
just shows a significant slow down in Karina's motion. The official
forecast track is just an extension of the previous advisory track,
and lies south of the consensus model TVCE, near the extreme
southern edge of the NHC guidance envelope.

The GFS-based SHIPS model indicates that the vertical shear is
expected to increase to near 20 kt during the 12-24 hour period,
while the shear vector veers around to the east. Given the
well-defined and small eye mentioned previously, some additional
strengthening is expected while Karina remains in favorable
thermodynamic and oceanic environments. By 36 hours and beyond, the
shear is forecast to decrease significantly, but this will occur
when the cyclone is moving over marginal SSTs. The result is that
a general leveling off of the intensity is expected, although there
could obviously be some fluctuations in the intensity due to
internal eyewall dynamics that can not be forecast this far in
advance. The official intensity forecast remains well above the
consensus model ICON due to the persistent weakening of Karina
shown by the GFDL and HWRF models thus far, and instead follows the
trend of the SHIPS and LGEM models.

FORECAST POSITIONS AND MAX WINDS

INIT 14/2100Z 17.1N 117.6W 65 KT 75 MPH
12H 15/0600Z 17.4N 119.1W 75 KT 85 MPH
24H 15/1800Z 17.8N 121.3W 80 KT 90 MPH
36H 16/0600Z 18.1N 123.6W 80 KT 90 MPH
48H 16/1800Z 18.2N 125.8W 80 KT 90 MPH
72H 17/1800Z 18.1N 129.5W 80 KT 90 MPH
96H 18/1800Z 17.7N 132.6W 75 KT 85 MPH
120H 19/1800Z 17.6N 134.2W 70 KT 80 MPH

$$
Forecaster Stewart

[meriland23]

Where did 90E go? Though it was to remain stationary for a possible fujiwara?

[Kingarabian]

Where did 90E go? Though it was to remain stationary for a possible fujiwara?

Variables in the tropics are subject to frequent changes.

[Hurricaneman]

Where did 90E go? Though it was to remain stationary for a possible fujiwara?

it became 94C from what I can see

[TheStormExpert]

Where did 90E go? Though it was to remain stationary for a possible fujiwara?

it became 94C from what I can see

Whelp there goes our chances of not seeing Ana till next year. Lol!

[hurricanes1234]

I'm not too keen on this intensifying much more if shear is going to be 20 knots soon.

[wxmann_91]

Not sure what the NHC is thinking about additional intensification. They acknowledge the forecasted increase in shear, and it's already stripping the LLC bare. Expected significant weakening in the next 24 hours. And the NHC has said the shear would decrease in a couple of days for a couple of days now. It may decrease finally when Karina moves over 22C waters, lol.

[supercane4867]

Not sure what the NHC is thinking about additional intensification. They acknowledge the forecasted increase in shear, and it's already stripping the LLC bare. Expected significant weakening in the next 24 hours. And the NHC has said the shear would decrease in a couple of days for a couple of days now. It may decrease finally when Karina moves over 22C waters, lol.

According to SHIPS the shear is supposed decrease to near zero while the hurricane is still over 26℃ waters, we've seen many cases this year that storms were able intensify in very marginal SST environment. Right now windshear maybe taking its toll but I don't see how it will not intensify again anymore.

[Yellow Evan]

I'm not too keen on this intensifying much more if shear is going to be 20 knots soon.

Where are you getting this from? There's nothing to indicate 20 knts of shear.

[Yellow Evan]

Not sure what the NHC is thinking about additional intensification. They acknowledge the forecasted increase in shear, and it's already stripping the LLC bare. Expected significant weakening in the next 24 hours. And the NHC has said the shear would decrease in a couple of days for a couple of days now. It may decrease finally when Karina moves over 22C waters, lol.

According to SHIPS the shear is supposed decrease to near zero while the hurricane is still over 26℃ waters, we've seen many cases this year that storms were able intensify in very marginal SST environment. Right now windshear maybe taking its toll but I don't see how it will not intensify again anymore.

This. It'll be low from day 2-5. It should be a steady state the next two days.

The shear did decrease. That's why Karina is a hurricane now.

[Kingarabian]

Not sure what the NHC is thinking about additional intensification. They acknowledge the forecasted increase in shear, and it's already stripping the LLC bare. Expected significant weakening in the next 24 hours. And the NHC has said the shear would decrease in a couple of days for a couple of days now. It may decrease finally when Karina moves over 22C waters, lol.

Visible imagery shows nothing new in terms of shear impact.



Same structure if not better.

Microwave shows a solid compact core with a strong eyewall that is open to the north.

AVN appear to be showing a warming eye.

No 22C water unless Karina jumps over 23N within the next 24 hours. Else, all we have is water temps that range from 28C-25C to the end of the forecast track.

[Yellow Evan]

Not sure what the NHC is thinking about additional intensification. They acknowledge the forecasted increase in shear, and it's already stripping the LLC bare. Expected significant weakening in the next 24 hours. And the NHC has said the shear would decrease in a couple of days for a couple of days now. It may decrease finally when Karina moves over 22C waters, lol.

Visible imagery shows nothing new in terms of shear impact.

http://i.imgur.com/sEYf372.jpg

Same structure if not better.

Microwave shows a solid compact core with a strong eyewall that is open to the north.

AVN appear to be showing a warming eye.

No 22C water unless Karina jumps over 23N within the next 24 hours. Else, all we have is water temps that range from 28C-25C to the end of the forecast track.

Shear is probs affecting but should IMO not limit slow intensification. Probs held a steady state since the last adv.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[TropicalAnalystwx13]

Karina is definitely weakening this evening. The eye that was visible on conventional satellite imagery earlier is gone, and the low-level circulation is starting to become discernible under upper-level clouds if you look at a RGB loop.

Upper-level winds have presented themselves as more of an issue than models indicated several days ago. My forecast of a major hurricane from this will very likely bust.

[Yellow Evan]

EP, 11, 2014081500, , BEST, 0, 170N, 1178W, 65, 989, HU, 34, NEQ, 40, 40, 50, 50, 1008, 240, 10, 0, 0, E, 0, , 0, 0, KARINA, D,
EP, 11, 2014081500, , BEST, 0, 170N, 1178W, 65, 989, HU, 50, NEQ, 20, 20, 20, 20, 1008, 240, 10, 0, 0, E, 0, , 0, 0, KARINA, D,
EP, 11, 2014081500, , BEST, 0, 170N, 1178W, 65, 989, HU, 64, NEQ, 10, 0, 0, 10, 1008, 240, 10, 0, 0, E, 0, , 0, 0, KARINA, D,

[Yellow Evan]

Karina is definitely weakening this evening. The eye that was visible on conventional satellite imagery earlier is gone, and the low-level circulation is starting to become discernible under upper-level clouds if you look at a RGB loop.

Upper-level winds have presented themselves as more of an issue than models indicated several days ago. My forecast of a major hurricane from this will very likely bust.

http://i.imgur.com/BWGfJC0.gif

It's likely going to fluctuate in intensity for a bit, like many EPAC storms. It should still find a way to intensify later on. This is much like Hernan 08 and Celia 10 in that regard.

SHEAR (KT) 17 20 17 13 19 12 11 7 9 6 3 6 2

Shear will decrease soon. Still think there's a halfway decent shot at becoming a major.

The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products.

[Kingarabian]

SAB/TAFB just came out with an increase to T4.5.

[Yellow Evan]

SAB/TAFB just came out with an increase to T4.5.

Likely since structure wise, it is unchanged. Just losing convection.

[Equilibrium]

weakens to a TS or maybe less. Par for the course.




The posts in this forum are NOT official forecast and should not be used as such. They are just the opinion of the poster and may or may not be backed by sound meteorological data. They are NOT endorsed by any professional institution or storm2k.org. For official information, please refer to the NHC and NWS products

[HurricaneRyan]

Karina came out of nowhere for me. Dang!

[Kingarabian]

TXPZ26 KNES 150020
TCSENP

A. 11E (KARINA)

B. 15/0000Z

C. 17.2N

D. 118.1W

E. THREE/GOES-W

F. T4.5/4.5/D1.5/24HRS

G. IR/EIR/VIS/TMI/AMSU

H. REMARKS...DT=4.5 BASED ON LG EMBEDDED CENTER. PT=4.5. MET=4.5. FT
IS BASED ON DT. EARLIER VISIBLE AND MICROWAVE SHOWS NASCENT EYE.

I. ADDL POSITIONS

14/1927Z 16.9N 117.6W TMI
14/2326Z 17.2N 117.8W AMSU


...SCHWARTZ