EPAC: KARINA - Post-Tropical

[Equilibrium]

just a area of 200 hpa potential velocity abnormalities in a ie,trade winds and convergence and divergence area. Not a kelvin wave .


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]

[cycloneye]

TROPICAL STORM KARINA DISCUSSION NUMBER 10
NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014
200 AM PDT FRI AUG 15 2014

Karina continues to experience 20-25 kt of easterly vertical wind
shear, which has caused the center to become partly exposed on the
eastern side of the deep convection. Satellite intensity estimates
are 65 kt from SAB and 55 kt from TAFB. The initial intensity is
decreased to 60 kt, and this may a little generous.

The initial motion is now 275/10. Karina remains on the south side
of a mid-level ridge that extends from the southwestern United
States westward over the Pacific. This feature should steer the
storm generally westward to west-northwestward for the next 2-3
days. After that time, the guidance becomes divergent, partly due
to how the models show Karina interacting with other nearby tropical
disturbances. The ECMWF and Canadian models forecast a low pressure
area east of Karina causing the cyclone to turn generally west-
southwestward. The UKMET and NAVGEM also show a low to the east.
However, they forecast it to have less influence on Karina, with the
UKMET showing a continued westward track and the NAVGEM showing a
turn toward the north. The GFS shows less development east of
Karina and instead forecasts the cyclone to interact with a
disturbance to the southwest, which causes Karina to continue
westward to west-northwestward. Given the uncertainty, the new
forecast track will follow the previous forecast in showing a
west-southwestward turn in best agreement with the ECMWF, HWRF, and
the Florida State Superensemble models. The new track lies to the
south of the center of the guidance envelope and the other consensus
models.

The dynamical models suggest the current shear could continue for
another 24-30 hours. Based on this and the current structure of
the storm, the early part of the intensity forecast is revised
significantly downward from the previous advisory. After that time,
the forecast remains tricky. The shear is expected to decrease
while Karina moves over sea surface temperatures of near 26C. This
could allow Karina to re-intensify as forecast by the GFDL and the
Navy COAMPS models. However, any deviation north of the forecast
track would take the system over colder water, which would prevent
strengthening. The possible interaction with the other disturbances
would also hinder re-intensification, and the Canadian model shows
Karina starting to get absorbed by the eastern disturbance near the
end of the forecast period. Since there are so many possibilities,
the latter part of the intensity forecast is low confidence. It
calls for Karina to maintain a 50 kt intensity from 24-120 hours,
which is stronger than much of the guidance.


FORECAST POSITIONS AND MAX WINDS

INIT 15/0900Z 17.2N 119.1W 60 KT 70 MPH
12H 15/1800Z 17.6N 120.7W 55 KT 65 MPH
24H 16/0600Z 18.1N 122.9W 50 KT 60 MPH
36H 16/1800Z 18.4N 125.0W 50 KT 60 MPH
48H 17/0600Z 18.4N 127.0W 50 KT 60 MPH
72H 18/0600Z 18.0N 131.0W 50 KT 60 MPH
96H 19/0600Z 17.5N 134.0W 50 KT 60 MPH
120H 20/0600Z 17.0N 136.5W 50 KT 60 MPH

$$
Forecaster Beven

[HurricaneTracker2031]

Karina weakened and my re-intensify later on. We will see.



Synopsis for Karina and other systems: http://goo.gl/8qLDkb

Personal Forecast Disclaimer:
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.

[hurricanes1234]

Reintensification seems unlikely to me. I'd say the chances of a major from this are <10%. I'd say there's a 50-55% chance it peaked yesterday as a Category 1.

[Yellow Evan]

EP, 11, 2014081512, , BEST, 0, 173N, 1197W, 55, 995, TS, 34, NEQ, 50, 50, 50, 50, 1007, 210, 20, 0, 0, E, 0, , 0, 0, KARINA, M,
EP, 11, 2014081512, , BEST, 0, 173N, 1197W, 55, 995, TS, 50, NEQ, 20, 20, 20, 20, 1007, 210, 20, 0, 0, E, 0, , 0, 0, KARINA, M,

[hurricanes1234]

Continues to weaken.

11E KARINA 140815 1200 17.3N 119.7W EPAC 55 995

[Yellow Evan]

Reintensification seems unlikely to me. I'd say the chances of a major from this are <10%. I'd say there's a 50-55% chance it peaked yesterday as a Category 1.

If all thing go right and no interaction occurs, it should re-intensify. Now, that's a big if.

Tbh, it looks much better now than last night.

[TropicalAnalystwx13]

The feature passing into West Atlantic is a moderate-strength convectively-coupled kelvin wave. Karina developed as the CCKW began to move through the East Pacific.

[Yellow Evan]

000
WTPZ41 KNHC 151452
TCDEP1

TROPICAL STORM KARINA DISCUSSION NUMBER 11
NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014
800 AM PDT FRI AUG 15 2014

Karina is displaying quite vigorous convection with very cold cloud
tops, but almost exclusively in the southwestern semicircle - a
classic symptom of moderate vertical shear. The 15-20 kt deep layer
shear continues to cause some weakening as the TAFB and SAB Dvorak
and CIMSS AMSU estimates suggest an intensity of around 55 kt. The
CIMSS ADT, on the other hand, does not recognize the shear pattern
in the deep convection and is likely substantially too high. The
current intensity is analyzed at 55 kt.

The short-term trend in intensity - primarily driven by the hostile
vertical shear - suggests some further weakening, which is
consistent with all the intensity guidance. The official intensity
forecast out through two days is thus slightly below that from the
previous advisory. In about 36 hours, the shear should abate some,
but the SSTs and atmospheric instability should decrease along the
forecast track. The guidance responds by making almost no change to
the intensity out through three days. At days four and five, some
of the guidance suggests a re-invigoration of Karina. However,
because of the rather high uncertainty of Karina's position and
possible interaction with other disturbances, the intensity forecast
shows no change at the long-lead predictions.

The initial motion is now 280/10. Karina remains on the south side
of a mid-level ridge that extends from the southwestern United
States westward over the Pacific. This feature should steer the
storm generally westward for the next couple of days with a slight
turn toward the west-southwest by day three. After that time, the
guidance becomes divergent, partly due to how the models show Karina
interacting with other nearby tropical disturbances. The ECMWF
model forecasts a low pressure area east of Karina causing the
cyclone to turn farther west-southwestward. The UKMET and NAVGEM
also show a low to the east. However, they forecast it to have less
influence on Karina, with the UKMET showing a continued westward
track and the NAVGEM showing a turn toward the north. The new GFS
has changed and now also shows a northward turn at day five. Given
the uncertainty, the new forecast track shows a west-southwestward
turn at day three followed by a westward shift by day five in best
agreement with the variable consensus model. The new forecast track
is nearly the same as the previous advisory, except slightly slower
to the west at days four and five.

FORECAST POSITIONS AND MAX WINDS

INIT 15/1500Z 17.4N 120.2W 55 KT 65 MPH
12H 16/0000Z 17.8N 121.9W 50 KT 60 MPH
24H 16/1200Z 18.1N 124.1W 45 KT 50 MPH
36H 17/0000Z 18.4N 126.2W 45 KT 50 MPH
48H 17/1200Z 18.4N 128.2W 45 KT 50 MPH
72H 18/1200Z 17.7N 131.6W 45 KT 50 MPH
96H 19/1200Z 17.5N 134.5W 45 KT 50 MPH
120H 20/1200Z 17.5N 135.5W 45 KT 50 MPH

$$
Forecaster Landsea

[Yellow Evan]

EP, 11, 2014081518, , BEST, 0, 175N, 1207W, 50, 998, TS, 34, NEQ, 50, 50, 50, 50, 1007, 210, 20, 0, 0, E, 0, , 0, 0, KARINA, M,
EP, 11, 2014081518, , BEST, 0, 175N, 1207W, 50, 998, TS, 50, NEQ, 20, 20, 20, 20, 1007, 210, 20, 0, 0, E, 0, , 0, 0, KARINA, M,

Probs was 50 knts a little earlier. Likely not weakening as fast.

[Yellow Evan]

* EAST PACIFIC SHIPS INTENSITY FORECAST *
* GOES AVAILABLE, OHC AVAILABLE *
* KARINA EP112014 08/15/14 18 UTC *

TIME (HR) 0 6 12 18 24 36 48 60 72 84 96 108 120
V (KT) NO LAND 50 47 44 43 42 41 41 42 42 44 45 47 48
V (KT) LAND 50 47 44 43 42 41 41 42 42 44 45 47 48
V (KT) LGE mod 50 47 45 43 42 40 39 38 38 38 38 39 40
Storm Type TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP TROP

SHEAR (KT) 11 13 14 12 9 6 7 13 9 8 10 7 10
SHEAR ADJ (KT) 0 1 0 -1 0 -2 0 -1 -3 -4 -3 -3 -5
SHEAR DIR 91 104 101 121 126 128 86 71 74 41 17 360 44
SST (C) 27.2 27.1 27.1 27.1 27.1 26.6 26.3 26.3 26.3 26.2 26.0 26.0 26.0

[cycloneye]

TROPICAL STORM KARINA DISCUSSION NUMBER 12
NWS NATIONAL HURRICANE CENTER MIAMI FL EP112014
200 PM PDT FRI AUG 15 2014

The cloud pattern associated with Karina has been gradually
deteriorating during the day. Microwave data reveal that the center
continues to be located to the north of a small area of deep
convection. The upper-level outflow is very limited due to
northeasterly shear. Consequently, the Dvorak T-numbers have
continued to decrease, supporting a generous initial intensity of 45
knots. It appears that Karina will continue within an environment
unfavorable for strengthening, but not hostile enough to weaken the
cyclone either. The NHC forecast calls for no change in intensity
during the next 5 days, although there is a small possibility of
slight strengthening beyond 4 days, when the cyclone reaches warmer
waters. In fact, this is the solution of the HWRF model.

The best estimate of the initial motion is 280 degrees at 10 knots.
Karina continues to be steered by the flow around a persistent
subtropical ridge. Most of the global models build the ridge
westward beyond 3 days, and this pattern should force Karina to move
on a more west to west-southwest track with a decrease in forward
speed. By day 5, Karina will probably begin to meander within a
very weak steering flow. The NHC forecast is similar to the previous
one and follows the trend of the multi-model consensus.

FORECAST POSITIONS AND MAX WINDS

INIT 15/2100Z 17.6N 121.2W 45 KT 50 MPH
12H 16/0600Z 18.0N 122.8W 45 KT 50 MPH
24H 16/1800Z 18.3N 125.0W 45 KT 50 MPH
36H 17/0600Z 18.3N 127.0W 45 KT 50 MPH
48H 17/1800Z 18.1N 129.0W 45 KT 50 MPH
72H 18/1800Z 17.5N 131.5W 45 KT 50 MPH
96H 19/1800Z 17.0N 134.0W 45 KT 50 MPH
120H 20/1800Z 17.0N 135.0W 45 KT 50 MPH

$$
Forecaster Avila

[TheStormExpert]

It looks like Karina is going to be on a weakening trend from here on out.

[Yellow Evan]

Who would have thought 24 hours ago we would have a sheared TS?

[Kingarabian]

We still have trouble forecasting shear. That's what I found out.

[Yellow Evan]

We still have trouble forecasting shear. That's what I found out.

Generally, in the EPAC, the shear trouble come with storms near the ITCZ. Karina is an oddity in this regard.

[Yellow Evan]

Just noticed something. This is the 3rd time in 4 advs the NHC said there estimate was generous.

[Steve820]

That was pretty unexpected, I guess Karina would only peak as a minimal hurricane. Wind shear is eating and tearing apart Karina, but this shear should hopefully subside so Karina could hang on.

[Yellow Evan]

That was pretty unexpected, I guess Karina would only peak as a minimal hurricane. Wind shear is eating and tearing apart Karina, but this shear should hopefully subside so Karina could hang on.

It could, but there's simply too much uncertainty IMO.