Hurricane Joaquin 2015

[WidreMann]

I'm not so sure a more southward motion explains the discrepancy between the Euro and the GFS anymore. The 12z Euro 24-hour position and the 18z GFS 18-hour position (same lead time) are almost identical. The Euro's 48-hour point is about due west, so presumably it doesn't get much farther south on the 12z Euro. To put simply, the GFS and Euro are in agreement on how far south this gets now. The key difference between the two models seems to be in the motion after the aforementioned time frame.

 

You do bring up a good point that the Euro has been leading the way on the more southward movement for the past day or so, which is one reason why I don't want to write it off just yet.

 

Edit: downeast beat me to it lol

Why would that matter? The Euro could be doing a good job on the southward movement, even if it's doing a bad job later on. There are a lot of types of weather going on, and models are better or worse in each. We can't assume that because it's currently doing well in one that it's automatically going to be doing well in all the others just because it's the same model, unless the thing it's doing well in right now significantly impacts the downstream outcome. Since the models are identical, as you say, that's not what is relevant here.

[Stormsfury]

No kidding...whats funny is, the model that usually overdoes trof and further east usually (GFS) and the euro over does ridges and is further west is the opposite. lol

lol. Ikr! This setup is so volatile right now and just subtle changes lead to huge differences, a true butterfly effect.

I'm stil not so sure the west trends stope at this point and so far, it's been the whole day trend. The fact that the 00z trop models continued west, now 5 showing SC landfall vs 2 earlier just adds more madness to the equation.

The point where Joaquin makes a turn initially wholeheartedly decidea where he ends up. I basically think a Carolinas landfall is a good bet at this time. Just where, I don't know but if I was to take a guess, I would say ILM. (disclaimer NOT a forecast!)

[RubiksDestroyer]

Just gonna add this in here...

 

GFS 18z was initialized with Joaquin having a pressure of 995 mb. This is obviously wrong, so I'm not yet convinced that its track can be fully trusted at this time. It may very well change once the newer, lower pressures are accounted for.

 

On the other hand, Joaquin appears to be slowing down/stationary, implying it may be beginning to turn further to the north. The European has the storm staying in the Bahamas for a longer period of time, consequentially missing the trough. This potential earlier turnaround means that the European may be wrong.

 

Overall, this is a very difficult forecast, and has a small gradient between one extreme and another.

[deltadog03]

Well....can't get much better than this right?

[Hoosier]

Just gonna add this in here...

 

GFS 18z was initialized with Joaquin having a pressure of 995 mb. This is obviously wrong, so I'm not yet convinced that its track can be fully trusted at this time. It may very well change once the newer, lower pressures are accounted for.

 

On the other hand, Joaquin appears to be slowing down/stationary, implying it may be beginning to turn further to the north. The European has the storm staying in the Bahamas for a longer period of time, consequentially missing the trough. This potential earlier turnaround means that the European may be wrong.

 

Overall, this is a very difficult forecast, and has a small gradient between one extreme and another.

 

 

Based on what mets here have said, the GFS not having the initial pressure correct is not really a big deal...

[Supercane]

Why would that matter? The Euro could be doing a good job on the southward movement, even if it's doing a bad job later on. There are a lot of types of weather going on, and models are better or worse in each. We can't assume that because it's currently doing well in one that it's automatically going to be doing well in all the others just because it's the same model, unless the thing it's doing well in right now significantly impacts the downstream outcome. Since the models are identical, as you say, that's not what is relevant here.

 

The poster I was quoting pointed out (correctly) that the Euro has been handling the southward motion better than all the other models and that the Euro stands a better chance of being accurate because of the continued southward motion. A lot of people have said that an out-to-sea track is more likely if the storm moves farther south (since it would presumably be too removed from the ULL to the west and more susceptible to the weakness in the central Atlantic). While that is probably true, my point was that something else is causing the Euro and the GFS to diverge now, since both are essentially aligned on how far south this goes.

[fountainguy97]

what its worth the 00z NAM way west at hour 60.  I believe it has been holding with Euro until now.

 

Very close to GFS track

[SN_Lover]

NAM SOAKS the GA/SC boarder. looking more like other models now except for strength. 

[SN_Lover]

what its worth the 00z NAM way west at hour 60.  I believe it has been holding with Euro until now.

 

Very close to GFS track

several hundred miles west....

[Lookout]

The poster I was quoting pointed out (correctly) that the Euro has been handling the southward motion better than all the other models and that the Euro stands a better chance of being accurate because of the continued southward motion. A lot of people have said that an out-to-sea track is more likely if the storm moves farther south (since it would presumably be too removed from the ULL to the west and more susceptible to the weakness in the central Atlantic). While that is probably true, my point was that something else is causing the Euro and the GFS to diverge now, since both are essentially aligned on how far south this goes.

the problem is the models have been trending further south with the upper level low at the same time.

 

edit..as others have noted.

 

[HKY_WX]

I'm tempted to go stock up on groceries tonight. A cat 3 hitting the NC coast on a WNW heading will give Raleigh 100mph winds. I am a little worried at this point.

[kvegas-wx]

I'm tempted to go stock up on groceries tonight. A cat 3 hitting the NC coast on a WNW heading will give Raleigh 100mph winds. I am a little worried at this point.

Pines be snappin'! I would recommend a generator first. This is hit or miss, not graze you as it passes by. A hit means days without power.

[fountainguy97]

Yep Nam says bye bye to Euro and lines up nicely with GFS so far for track.  EURO completely alone.  A few forecasters still holding to EURO but have to say the odds are not in its favor this time around.  I don't care how "Accurate" a model is if it is completely alone you have to go with the majority imo. Unless, of course, ALL the other models have a issue with data which is extremely unlikely

[Lookout]

nam actually makes landfall in south carolina..although it stalls it there. it's garbage really at this range but its important imo it no longer shows the out to sea track.

[WidreMann]

I'm tempted to go stock up on groceries tonight. A cat 3 hitting the NC coast on a WNW heading will give Raleigh 100mph winds. I am a little worried at this point.

You don't think it won't get sheared a bit before landfall?

[84 Hour NAM]

Yep Nam says bye bye to Euro and lines up nicely with GFS so far for track.  EURO completely alone.  A few forecasters still holding to EURO but have to say the odds are not in its favor this time around.  I don't care how "Accurate" a model is if it is completely alone you have to go with the majority imo. Unless, of course, ALL the other models have a issue with data which is extremely unlikely

The NAM hardly matters at this range. It's the worst major model on the planet.

[btownheel]

I'm tempted to go stock up on groceries tonight. A cat 3 hitting the NC coast on a WNW heading will give Raleigh 100mph winds. I am a little worried at this point.

 

 

That's the dilemma I'm having.  If it hit's the coast at 135 and comes WNW.....I figure that's still probably 85 sustained with gusts pushing 100 when it makes it to MBY here in Burlington,.  That would make it easily the strongest storm I've ever seen come through here (Fran was 50-ish when it was here if I recall correctly).

 

85 mph winds and 12 inches of rain (especially considering the rain is kicking off now) is an absolute disaster.  Huge flooding on the Haw and massive power outages statewide.  If it crosses the state as modeled at that strength, it will take the better part of the month for some people to get juice back....

 

The nightmare scenario is having it track right up 64 as it turns inland.  Puts Greenville/RDU/Chapel Hill/Greensboro right on the strongest northeast wall...

[Stormsfury]

Official Joaquin 115 mph CAT 3. 951 MB pressure.

[SN_Lover]

You don't think it won't get sheared a bit before landfall?

It would experience a positive trough interaction coupled with warm waters. Could actually help it. Gonna be like sandy with expanding wind field. 

[fountainguy97]

We all are aware of the crappage of the NAM, but the single fact that it no longer supports the EURO is definitely worth noting.

[Solak]

1100 PM EDT WED SEP 30 2015

Joaquin has rapidly intensified during the past 24 hours with the

satellite presentation continuing to improve this evening. The eye

has recently become apparent near the center of the very symmetric

central dense overcast. An Air Force Reserve Hurricane Hunter

aircraft that has been investigating the hurricane this evening has

measured peak 700 mb flight-level winds of 113 kt and 102 kt surface

winds from the SFMR. These data support an initial intensity of

100 kt, making Joaquin the second major hurricane of the 2015

Atlantic hurricane season. NOTE: Communications problems have

delayed the public release of the Air Force reconnaissance data.

Joaquin continues to move slowly southwestward with an initial

motion estimate of 220/5 kt. The hurricane is forecast to move

slowly southwestward or west-southwestward for another 24 hours or

so while it remains to the south of a narrow northeast to southwest

oriented ridge. This ridge is expected to weaken by Friday as a

trough deepens and cuts off over the southeastern United States.

This should cause Joaquin to turn northward within 48 hours. The 18Z

runs of the GFS and HWRF remain in general agreement with the 12Z

UKMET and Canadian models moving Joaquin around the northeastern

portion of the cut-off low and bring the hurricane inland over the

Carolinas or mid-Atlantic states. The 12Z ECMWF remains the outlier

by showing a track toward the northeast out to sea. The NHC

forecast continues to follow the trend of the bulk of the guidance

and takes Joaquin toward the U.S east coast. The NHC track is

similar to the previous advisory and is once again east of the

multi-model consensus. The NOAA G-IV aircraft has recently

completed its synoptic surveillance flight, and data collected

during this mission should be assimilated into the 0000 UTC models,

hopefully reducing the spread of the track guidance.

The upper-level wind pattern over the hurricane is forecast by the

global models to become even more conducive during the next couple

of days. This favors additional intensification, with the only

possible limiting factors being upwelling of cool SSTs beneath the

slow-moving hurricane and eyewall cycles which could cause some

fluctuations in intensity. By 72 hours, increasing southwesterly

shear, dry air intrusion, and lower SSTs are expected to cause

gradual weakening. The updated NHC intensity forecast has been

significantly increased from the previous advisory primarily due to

the higher initial intensity. The official forecast is between the

lower statistical guidance and the higher HWRF during the first

36-48 hours, and is near the SHIPS/LGEM guidance after that time.

KEY MESSAGES:

1. Preparations to protect life and property within the warning

areas in the Central Bahamas should be completed now.

2. Confidence in the details of the forecast after 72 hours remains

low, since we have one normally excellent model that keeps Joaquin

far away from the United States east coast. The range of possible

outcomes is still large, and includes the possibility of a major

hurricane landfall in the Carolinas.

3. Every effort is being made to provide the forecast models with

as much data as possible. The NOAA G-IV jet has begun a series of

missions in the storm environment, and the National Weather Service

has begun launching extra balloon soundings.

4. Because landfall, if it occurs, is still more than three days

away, it's too early to talk about specific wind, rain, or surge

impacts from Joaquin in the United States. Regardless of Joaquin's

track, strong onshore winds will create minor to moderate coastal

flooding along the coasts of the mid-Atlantic and northeastern

states through the weekend.

5. A hurricane watch for a portion of the U.S. coast could be

required as early as Thursday evening.

6. Many portions of the eastern U.S. are currently experiencing

heavy rains and gusty winds associated with a frontal system. These

heavy rains are likely to continue for the next few days, even if

the center of Joaquin stays offshore. The resulting inland flood

potential could complicate preparations for Joaquin should it head

toward the coast, and even more substantial inland flooding is

possible if Joaquin later passes near or over these same areas.

FORECAST POSITIONS AND MAX WINDS

INIT 01/0300Z 23.8N 73.1W 100 KT 115 MPH

12H 01/1200Z 23.5N 73.8W 110 KT 125 MPH

24H 02/0000Z 23.6N 74.5W 120 KT 140 MPH

36H 02/1200Z 24.7N 74.8W 120 KT 140 MPH

48H 03/0000Z 26.6N 74.7W 110 KT 125 MPH

72H 04/0000Z 31.6N 74.7W 95 KT 110 MPH

96H 05/0000Z 36.2N 75.6W 85 KT 100 MPH

120H 06/0000Z 38.5N 76.5W 55 KT 65 MPH

[HKY_WX]

You don't think it won't get sheared a bit before landfall?

I haven't delved into the intensity forecasts yet. I'm sure some interaction with that upper low will cause some shearing on the southwest sides of the cane. However the ridging to the north is generally very favorable for intenisification up until landfall. This setup is not too far off of Hugo. 

[fountainguy97]

Also NHC with 11pm updates has Joaquin hitting 140mph wind.... so cat 5 is possible tomorrow

[Lookout]

Official Joaquin 115 mph CAT 3. 951 MB pressure.

really really surprised they didn't shift the track. i guess they are waiting on the full 0z suite but they are considerably further east than most of the guidance without giving much of a real reason why.

[Wow]

A Cat 4 hurricane with landfall in SC heading WNW.  Sounds familiar.

[Solak]

Just a bit different from just 48 hours ago...

FORECAST POSITIONS AND MAX WINDSINIT  29/0300Z 26.7N  70.4W   35 KT  40 MPH 12H  29/1200Z 26.9N  71.0W   40 KT  45 MPH 24H  30/0000Z 27.1N  72.0W   40 KT  45 MPH 36H  30/1200Z 27.2N  72.8W   45 KT  50 MPH 48H  01/0000Z 27.4N  73.4W   50 KT  60 MPH 72H  02/0000Z 28.6N  74.0W   55 KT  65 MPH 96H  03/0000Z 32.4N  74.0W   55 KT  65 MPH120H  04/0000Z 38.0N  74.0W   55 KT  65 MPH

[No snow for you]

I have called for a South Carolina landfall. The nam, even though bad at that range, continues the landfall south. This thing ends up in gsp and the shoots north.

[LMA1973]

I'm tempted to go stock up on groceries tonight. A cat 3 hitting the NC coast on a WNW heading will give Raleigh 100mph winds. I am a little worried at this point.

 

 

Hold on man, dont start panicking yet. WCS you still have til Sat morning or so to prep. Nothing to run out for at 10:00 on Thurs night

[fountainguy97]

It won't be a cat 4 at landfall.  ULL interaction and change to a hybrid storm will weaken it but expand the wind field I expect. 

[Lookout]

 

Just a bit different from just 48 hours ago...

FORECAST POSITIONS AND MAX WINDSINIT  29/0300Z 26.7N  70.4W   35 KT  40 MPH 12H  29/1200Z 26.9N  71.0W   40 KT  45 MPH 24H  30/0000Z 27.1N  72.0W   40 KT  45 MPH 36H  30/1200Z 27.2N  72.8W   45 KT  50 MPH 48H  01/0000Z 27.4N  73.4W   50 KT  60 MPH 72H  02/0000Z 28.6N  74.0W   55 KT  65 MPH 96H  03/0000Z 32.4N  74.0W   55 KT  65 MPH120H  04/0000Z 38.0N  74.0W   55 KT  65 MPH

i can't get over the fact it was forecasted to dissipate initially..now a solid cat 4 is forecasted. pretty amazing and a testament to how much there is to go in forecasting these things.