What the heck is going on with the global models re Chris?

This is the general tropical discussion area. Anyone can take their shot at predicting a storms path.

Moderator: S2k Moderators

Forum rules

The posts in this forum are NOT official forecasts 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. For official information, please refer to products from the National Hurricane Center and National Weather Service.

Help Support Storm2K
Message
Author
User avatar
x-y-no
Category 5
Category 5
Posts: 8359
Age: 65
Joined: Wed Aug 11, 2004 12:14 pm
Location: Fort Lauderdale, FL

What the heck is going on with the global models re Chris?

#1 Postby x-y-no » Wed Aug 02, 2006 7:29 am

Unbelievable ...

The GFS, NAM, ECMWF are still initializing Chris as an open wave ... I just don't get it.

The UKMET at least initializes a closed low, but only 1016mb.


As long as this massive error in initalization continues, I don't see that any of the models can be relied on, since they all run on some global model grid.
0 likes   

Josephine96

#2 Postby Josephine96 » Wed Aug 02, 2006 7:31 am

Maybe they think it'll go over Hispanola or Cuba and get destroyed
0 likes   

User avatar
deltadog03
Professional-Met
Professional-Met
Posts: 3580
Joined: Tue Jul 05, 2005 6:16 pm
Location: Macon, GA

#3 Postby deltadog03 » Wed Aug 02, 2006 7:32 am

Models are absolutely crappy right now. Global models have never been very good on tropical wx but, this is down right crappy.
0 likes   

User avatar
x-y-no
Category 5
Category 5
Posts: 8359
Age: 65
Joined: Wed Aug 11, 2004 12:14 pm
Location: Fort Lauderdale, FL

#4 Postby x-y-no » Wed Aug 02, 2006 7:34 am

Josephine96 wrote:Maybe they think it'll go over Hispanola or Cuba and get destroyed


No, I'm talking about the initialization - the 0 hour frame.

Chris has been a 60mph TS with a 1003mb central pressure since last night - yet all the 0Z model runs initialized an open wave with the exception of the UKMET which initialized a 1016mb low.

That's incomprehensible to me. Guess I really don't understand how the model initialization really works (or rather doesn't).
0 likes   

Derek Ortt

#5 Postby Derek Ortt » Wed Aug 02, 2006 7:36 am

50% of the initialization is the previous forecast

If the previous forecast is an open wave, chances are, the new initialization will be an open wave
0 likes   

Eyewall

#6 Postby Eyewall » Wed Aug 02, 2006 7:36 am

i was wondering the same thing like 2 days ago...

makes no sense to me :?:
0 likes   

User avatar
x-y-no
Category 5
Category 5
Posts: 8359
Age: 65
Joined: Wed Aug 11, 2004 12:14 pm
Location: Fort Lauderdale, FL

#7 Postby x-y-no » Wed Aug 02, 2006 7:43 am

Derek Ortt wrote:50% of the initialization is the previous forecast

If the previous forecast is an open wave, chances are, the new initialization will be an open wave


OK ... but how long should that go on? This was a TD 36 hours ago, and a TS for 12 hours before last night's 0Z runs were started. It seems ridiculous to me that an error like this could persist so long.

There's some real problem in how they initialize models if this can happen, IMHO.
0 likes   

bucman1
Category 1
Category 1
Posts: 394
Joined: Mon Sep 13, 2004 7:59 am

#8 Postby bucman1 » Wed Aug 02, 2006 8:08 am

How will this affect the projected track?
0 likes   

User avatar
DESTRUCTION5
Category 5
Category 5
Posts: 4423
Age: 43
Joined: Wed Sep 03, 2003 11:25 am
Location: Stuart, FL

#9 Postby DESTRUCTION5 » Wed Aug 02, 2006 8:12 am

x-y-no wrote:
Derek Ortt wrote:50% of the initialization is the previous forecast

If the previous forecast is an open wave, chances are, the new initialization will be an open wave


OK ... but how long should that go on? This was a TD 36 hours ago, and a TS for 12 hours before last night's 0Z runs were started. It seems ridiculous to me that an error like this could persist so long.

There's some real problem in how they initialize models if this can happen, IMHO.


I have to ask the same question...How the heck is this possible for none of these models to not be able to pick up on a near Cane..
0 likes   

Derek Ortt

#10 Postby Derek Ortt » Wed Aug 02, 2006 8:17 am

because none of the previous forecasts has Chris, and Chris has not passed over any data bouys. FL data is not assimilated into the models
0 likes   

User avatar
DESTRUCTION5
Category 5
Category 5
Posts: 4423
Age: 43
Joined: Wed Sep 03, 2003 11:25 am
Location: Stuart, FL

#11 Postby DESTRUCTION5 » Wed Aug 02, 2006 8:19 am

Derek Ortt wrote:because none of the previous forecasts has Chris, and Chris has not passed over any data bouys. FL data is not assimilated into the models


Ahh makes sense but Im thinking it needs to be revamped for that reason alone...
0 likes   

User avatar
x-y-no
Category 5
Category 5
Posts: 8359
Age: 65
Joined: Wed Aug 11, 2004 12:14 pm
Location: Fort Lauderdale, FL

#12 Postby x-y-no » Wed Aug 02, 2006 8:26 am

Derek Ortt wrote:because none of the previous forecasts has Chris, and Chris has not passed over any data bouys. FL data is not assimilated into the models


Given the manifestly nonsensical result, maybe they ought to reconsider this policy.
0 likes   

Derek Ortt

#13 Postby Derek Ortt » Wed Aug 02, 2006 8:33 am

the model would almost certainly reject the FL data since it is only at one level. Would probably be filtered out as noise

Now, dropsondes would be a different story
0 likes   

wxwonder12
Tropical Storm
Tropical Storm
Posts: 199
Joined: Thu May 12, 2005 11:29 am

#14 Postby wxwonder12 » Wed Aug 02, 2006 8:36 am

At what point will the models have better initialization and have a better grasp on forecast path??
0 likes   

User avatar
SouthFloridawx
S2K Supporter
S2K Supporter
Posts: 8346
Age: 46
Joined: Tue Jul 26, 2005 1:16 am
Location: Sarasota, FL
Contact:

#15 Postby SouthFloridawx » Wed Aug 02, 2006 8:39 am

Well looking at the gfs and nogaps it does look like they take it more northerly.
0 likes   

User avatar
x-y-no
Category 5
Category 5
Posts: 8359
Age: 65
Joined: Wed Aug 11, 2004 12:14 pm
Location: Fort Lauderdale, FL

#16 Postby x-y-no » Wed Aug 02, 2006 8:41 am

Derek Ortt wrote:the model would almost certainly reject the FL data since it is only at one level. Would probably be filtered out as noise

Now, dropsondes would be a different story



So maybe that would be the way to go. I'm not arguing for any given methodology, since I don't have the knowledge to do so. I'm just saying there's a big problem if the globals are still initializing an open wave when we've had a cyclone for over a full day.
0 likes   

User avatar
AJC3
Admin
Admin
Posts: 4024
Age: 61
Joined: Tue Aug 31, 2004 7:04 pm
Location: Ballston Spa, New York
Contact:

#17 Postby AJC3 » Wed Aug 02, 2006 8:49 am

x-y-no wrote:
Derek Ortt wrote:the model would almost certainly reject the FL data since it is only at one level. Would probably be filtered out as noise

Now, dropsondes would be a different story



So maybe that would be the way to go. I'm not arguing for any given methodology, since I don't have the knowledge to do so. I'm just saying there's a big problem if the globals are still initializing an open wave when we've had a cyclone for over a full day.


There's also the concept of "vortex bogussing", where a symmetric vortex representing the TC is is actually added to the model init. I'm, not sure if this is or has ever been done operationally with any of the globals. I seem to recall that it has, but I could be wrong. If you have time google the phrase and see what you come up with.
0 likes   

curtadams
S2K Supporter
S2K Supporter
Posts: 1122
Joined: Sun Aug 28, 2005 7:57 pm
Location: Orange, California
Contact:

#18 Postby curtadams » Wed Aug 02, 2006 9:34 am

Well, it passed over a buoy during its formation and they should have wind readings from the islands showing Nly winds. There's quickscat too, which showed a clearly closed low as of yesterday morning my time at the latest. How hard do they have to get whacked over the head? It really seems like something's wrong that they still see nothing. FWIW, most seem to think it will get somewhat stronger over the next few days so IMO they're doing better with its evolution, at least, than they did prior to TD status.
0 likes   

MWatkins
S2K Supporter
S2K Supporter
Posts: 2574
Joined: Sat Oct 12, 2002 7:51 pm
Location: SE Florida
Contact:

#19 Postby MWatkins » Wed Aug 02, 2006 10:46 am

The GFS is at it again...poor initialization without a well defined circulation at 500MB:

http://www.nco.ncep.noaa.gov/pmb/nwprod ... 0_000m.gif

Watch the upper features for the track because once again the model depiction of it will be worthless.

MW
0 likes   
Updating on the twitter now: http://www.twitter.com/@watkinstrack

User avatar
vacanechaser
Category 5
Category 5
Posts: 1461
Joined: Wed Dec 03, 2003 9:34 pm
Location: Portsmouth, Va
Contact:

#20 Postby vacanechaser » Wed Aug 02, 2006 1:05 pm

lets also remember the gfs could not see a major hurricane, fabian headed for bermuda for several days... well, maybe it saw it, but certainly not a major hurricane in 2004


Jesse V. Bass III
http://www.vastormphoto.com
Hurricane Intercept Research Team
0 likes   
Jesse V. Bass III
http://www.vastormphoto.com
Hurricane Intercept Research Team


Return to “Talkin' Tropics”

Who is online

Users browsing this forum: Google Adsense [Bot], ouragans and 29 guests