Shaggy
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Tropical Karen
- Thread starter GaWx
- Start date
Downeastnc
Member
0Z UKMET: 350 miles S of 12Z implying increased US threat despite it being weak. Much further S (~350 miles) vs the 12Z and therefore implies an increased CONUS threat despite keeping her weak. Regardless, my current concern is for all of the models: is there a new center much further west? If so, none of the models so far are initializing this. This would mean less trust than normal in the models until the true center is known.
TROPICAL STORM KAREN ANALYSED POSITION : 18.6N 65.0W
ATCF IDENTIFIER : AL122019
LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 25.09.2019 0 18.6N 65.0W 1008 29
1200UTC 25.09.2019 12 21.3N 64.9W 1008 28
0000UTC 26.09.2019 24 23.5N 63.7W 1008 26
1200UTC 26.09.2019 36 25.5N 63.0W 1008 25
0000UTC 27.09.2019 48 27.2N 62.1W 1008 24
1200UTC 27.09.2019 60 27.8N 61.0W 1007 28
0000UTC 28.09.2019 72 28.3N 60.9W 1005 37
1200UTC 28.09.2019 84 28.8N 62.4W 1006 30
0000UTC 29.09.2019 96 28.9N 64.7W 1007 29
1200UTC 29.09.2019 108 29.1N 67.0W 1006 30
0000UTC 30.09.2019 120 28.9N 68.4W 1004 35
1200UTC 30.09.2019 132 28.6N 70.1W 1004 34
0000UTC 01.10.2019 144 28.3N 71.9W 1004 32
TROPICAL STORM KAREN ANALYSED POSITION : 18.6N 65.0W
ATCF IDENTIFIER : AL122019
LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
0000UTC 25.09.2019 0 18.6N 65.0W 1008 29
1200UTC 25.09.2019 12 21.3N 64.9W 1008 28
0000UTC 26.09.2019 24 23.5N 63.7W 1008 26
1200UTC 26.09.2019 36 25.5N 63.0W 1008 25
0000UTC 27.09.2019 48 27.2N 62.1W 1008 24
1200UTC 27.09.2019 60 27.8N 61.0W 1007 28
0000UTC 28.09.2019 72 28.3N 60.9W 1005 37
1200UTC 28.09.2019 84 28.8N 62.4W 1006 30
0000UTC 29.09.2019 96 28.9N 64.7W 1007 29
1200UTC 29.09.2019 108 29.1N 67.0W 1006 30
0000UTC 30.09.2019 120 28.9N 68.4W 1004 35
1200UTC 30.09.2019 132 28.6N 70.1W 1004 34
0000UTC 01.10.2019 144 28.3N 71.9W 1004 32
accu35
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- Jan 5, 2017
- Messages
- 8,660
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Larry, do you think Karen could gain some strength little more then what models are showing? Obviously if the center reforms further west with the storm and doesn't go as far north before the turn, then it could gain some steam as it approaches Florida straits into the gulf well before the trough come through?
Downeastnc
Member
Radar does not indicate much of a LLC at the 11 pm NHC position....recon is finding a weakening LLC in that area as well.....
What a mess but holy cow that is some big storms firing. My guess is we should see a new LLC form under that if that should continue.
Yes that sounds reasonable.
0Z Euro: interesting run that sort of resembles that 0Z Sun run that hit Cuba before heading back up into the SE Gulf. This one is a bit different: Karen is much weaker/very weak and she stays near Cuba for awhile and may never reach the Gulf.
Downeastnc
Member
Looks like Karen is firing storms over the center now and the big complex to the west is fading.....so a center relocation seems unlikely.
0Z EPS prelim has 8 CONUS hits out of 51 (16%) (TCs 1003 mb or stronger) vs 14% 12Z and 16% 24 hours ago:
1. 10/2 Cape Canav. H
2. 10/2 SE FL H
3. 10/3 SE FL TD
4. 10/3 St. Aug. H
5. 10/3 Melbourne TS
6. 10/5 LA/MS/AL H
7. 10/6 Vero TS
8. 10/8 W Fl Panhandle H
1. 10/2 Cape Canav. H
2. 10/2 SE FL H
3. 10/3 SE FL TD
4. 10/3 St. Aug. H
5. 10/3 Melbourne TS
6. 10/5 LA/MS/AL H
7. 10/6 Vero TS
8. 10/8 W Fl Panhandle H
Shaggy
Member
pretty good write up by nhc about her future strength and why models show dissipation versus strengthening. The question is what will the models do with a properly initialized and stronger storm in future runs? Will stronger equal more west in the GOM or more poleward and towards the SE before a safe recurve? Might be some model surprises yet with karen.
looks like this ridge may hurt Karen in a way, if it’s weak and exposed already, it’s just gonna die with dry air entrainment like that, most of that dry air is subsidence from the ridge... 
Downeastnc
Member
You would think that but the NHC seems bullish on Karen and strengthening regardless of the dry air..
The main reasons for global
models weakening the cyclone is due to the low- and upper-level
circulations decoupling in about 3 days, followed by very dry
mid-level overspreading of the low-level circulation, shutting
off convective development. The problem with that scenario is that
Karen will be moving into very low vertical shear conditions and
underneath an upper-level anticyclone by 36 hours, which favors
strengthening since the cyclone will also be sitting over 29 deg C
water of considerable depth. For now, the new official intensity
forecast remains a compromise between the weak dynamical model
solutions and the stronger SHIPS intensity forecasts,
Also they mentioned this in yesterday mornings discussion....the proverbial fly in the ointment
However, if Karen strengthens as currently expected, then the cyclone's robust circulation should be able to mix out any dry air intrusions, allowing for at least additional modest intensification to occur in the 72-120 hour period.
**Interesting I've noticed forecaster Stewart is the 5 am discussion writer and seems to be leaning towards a better organized and strengthening system, other forecasters not so much, differing opinions at NHC, Lol
It is interesting to note that the EPS members that do move it west strengthens it, just needs to work on getting a solid core before it does so
Yeah it definitely will need to develop a solid core if it's going to fight off the dry air down the road
B
Brick Tamland
Guest
Ethan80963!
Member
She has the NHC perplexed I see....
Except for the possibility of dry air in the circulation, it's not
quite evident why Karen has not been able to sustain organization.
Still, the cyclone is expected to move beneath an upper-level
anticyclone during the next 24-48 hours, and if the shear does
indeed decrease, then some strengthening would be expected. There
continues to be a dichotomy among the intensity models, with the
dynamical models (including the GFS and ECMWF) keeping the cyclone
weak while the statistical-dynamical models still show
intensification through days 4 and 5. It's difficult to ignore
what's being shown by the global models, since there must be
something in the environment that they're deeming to be negative
for continued strengthening.
Except for the possibility of dry air in the circulation, it's not
quite evident why Karen has not been able to sustain organization.
Still, the cyclone is expected to move beneath an upper-level
anticyclone during the next 24-48 hours, and if the shear does
indeed decrease, then some strengthening would be expected. There
continues to be a dichotomy among the intensity models, with the
dynamical models (including the GFS and ECMWF) keeping the cyclone
weak while the statistical-dynamical models still show
intensification through days 4 and 5. It's difficult to ignore
what's being shown by the global models, since there must be
something in the environment that they're deeming to be negative
for continued strengthening.
Ethan80963!
Member
INIT 25/1500Z 21.7N 64.9W 40 KT 45 MPH
12H 26/0000Z 23.4N 64.4W 45 KT 50 MPH
24H 26/1200Z 25.4N 63.7W 45 KT 50 MPH
36H 27/0000Z 26.9N 62.9W 50 KT 60 MPH
48H 27/1200Z 27.5N 62.0W 55 KT 65 MPH
72H 28/1200Z 26.8N 62.0W 55 KT 65 MPH
96H 29/1200Z 26.0N 65.0W 55 KT 65 MPH
120H 30/1200Z 25.5N 68.5W 55 KT 65 MPH
Ethan80963!
Member
Sure does, it almost appears Karen actually absorbs what's left of Jerry....semantics I know. It did initialize Karen too weak and Jerry a little too strong, either way it does head west but I'm starting to think this is going to be a non-issue for the US, unless... UNLESSS, Karen actually finally becomes organized and develops a solid inner core.
And it stalls it out well NE of the Bahamas and eventually dissipates
Last edited:
Ethan80963!
Member
AF300 has taken off and on its way to Karen
12Z UKMET: inititialized about 35 miles too far N (21.6N instead of 21.1N); moves her further east (all the way to 58.4W) and then dissipates her at 96:
TROPICAL STORM KAREN ANALYSED POSITION : 21.6N 65.0W
ATCF IDENTIFIER : AL122019
LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 25.09.2019 0 21.6N 65.0W 1008 30
0000UTC 26.09.2019 12 23.9N 64.0W 1008 28
1200UTC 26.09.2019 24 26.2N 63.1W 1008 26
0000UTC 27.09.2019 36 27.9N 61.2W 1009 24
1200UTC 27.09.2019 48 28.5N 59.5W 1008 30
0000UTC 28.09.2019 60 29.5N 58.4W 1009 27
1200UTC 28.09.2019 72 30.1N 59.5W 1010 22
0000UTC 29.09.2019 84 29.7N 61.6W 1010 23
1200UTC 29.09.2019 96 CEASED TRACKING
TROPICAL STORM KAREN ANALYSED POSITION : 21.6N 65.0W
ATCF IDENTIFIER : AL122019
LEAD CENTRAL MAXIMUM WIND
VERIFYING TIME TIME POSITION PRESSURE (MB) SPEED (KNOTS)
-------------- ---- -------- ------------- -------------
1200UTC 25.09.2019 0 21.6N 65.0W 1008 30
0000UTC 26.09.2019 12 23.9N 64.0W 1008 28
1200UTC 26.09.2019 24 26.2N 63.1W 1008 26
0000UTC 27.09.2019 36 27.9N 61.2W 1009 24
1200UTC 27.09.2019 48 28.5N 59.5W 1008 30
0000UTC 28.09.2019 60 29.5N 58.4W 1009 27
1200UTC 28.09.2019 72 30.1N 59.5W 1010 22
0000UTC 29.09.2019 84 29.7N 61.6W 1010 23
1200UTC 29.09.2019 96 CEASED TRACKING
GFS does the loop and is heading west but also very weak and weakening.... anything can happen but there's really not a model out there that develops Karen. Seems odd in that location, under that high..
And then the 12Z GFS at 138 hits that brick wall well offshore FL that many models have been seeing.
And then she starts moving W again though weak. Moderate shear along most of the path.
Edit: Then later she (very weak) recurves just E of the Bahamas. And then she degenerates to a wave.
Last edited:
Ya this one is puzzling. should be in a better environment now. That ULL to its W and SW should be helping karen strengthen. but it's not.
Best I can tell.she is moving almost due N right now?
Euro also shows Karen dissipating after the westward turn, obviously will continue to watch but I think the writing is on the wall with this one
Ethan80963!
Member
Shaggy
Member
If she was showing us a bit of life we could discount the models that dissipate her. As it stands they seem to be more right at the present time based on her poor condition.
S
snowcool776
Guest
CEASED TRACKING - Basically means this system is done. No need to go in further.
S
snowcool776
Guest
Happy Hour looks fine, doesn't want anymore reintensification before dying.
Brent
Member
NHC has way backed off on the forecast and now mentions the possibility of dissipation
It's probably time to put more weight on the dynamical models for
Karen's future intensity. The cyclone has continued to struggle
in its environment, which is essentially what those models have been
indicating all along. Even the statistical-dynamical models, which
are explicitly showing strengthening, indicate that the environment
won't be very favorable, with convergence aloft and a dry mid-level
air mass. Because of those factors, and the lower initial
intensity, the NHC intensity forecast has been lowered considerably
from this morning's forecast. It still allows for the possibility
of some strengthening, but if model trends continue, the official
forecast could be lowered further in subsequent advisories. And if
the global models are correct, Karen could even lose deep
convection, and hence become post-tropical, in about 3 days.
It's probably time to put more weight on the dynamical models for
Karen's future intensity. The cyclone has continued to struggle
in its environment, which is essentially what those models have been
indicating all along. Even the statistical-dynamical models, which
are explicitly showing strengthening, indicate that the environment
won't be very favorable, with convergence aloft and a dry mid-level
air mass. Because of those factors, and the lower initial
intensity, the NHC intensity forecast has been lowered considerably
from this morning's forecast. It still allows for the possibility
of some strengthening, but if model trends continue, the official
forecast could be lowered further in subsequent advisories. And if
the global models are correct, Karen could even lose deep
convection, and hence become post-tropical, in about 3 days.