Tropical Storm Erika

[IsentropicLift]

I think we all know that Erika has a difficult road the next 2-3 days. We're here a bit with stating the obvious. Right now Erika is experiencing a major convective blowup on the East side and outflow looks much better.

[turtlehurricane]

Yeah I'm not exactly sure I agree TH. The GFS and EC are pretty valuable. The GFS as DTK noted, has done pretty well. Everyone has to flush out the Sandy bullsh*t. I remember (I believe earlier that year) when the euro took Debbie as a hurricane into Galveston while the GFS took it harmlessly into the FL panhandle a few days out. EC did not win that one.

The GFS literally can't resolve a tropical cyclone. It is a classic mid-latitude forecaster mistake to use global models for tropical cyclone forecasting. They are useful for determining larger scale steering currents, but not for actually projecting a tropical cyclone.

 

The GFS and euro do better than other global models, since the other ones aren't even useful (CMC? JMA?). It's like picking out the best piece of garbage. I'm actually amused at the ignorance displayed by a few of you, I am saying nothing ground breaking here.

[turtlehurricane]

Stats tell otherwise, present your facts, otherwise I'll think you are pulling this out your arse, which wouldn't be a first.

I already said the facts.... global models can barely resolve tropical cyclones, and there's not enough data to initialize with anyways. The equations aren't particularly optmal for tropical forecasting either, they are designed for mid-latitue weather. Higher resolution models with equations that are tuned for hurricanes are a much better option, although we still got a long way to go even with those.

 

This is all well known, at least for real tropical cyclone modelers and forecasters. I am just re-iterating what the experts already know.

[Superstorm93]

I think we all know that Erika has a difficult road the next 2-3 days. We're here a bit with stating the obvious. Right now Erika is experiencing a major convective blowup on the East side and outflow looks much better.

 

...Well south of its actual center 

 

[28storms]

I already said the facts.... global models can barely resolve tropical cyclones, and there's not enough data to initialize with anyways. The equations aren't particularly optmal for tropical forecasting either, they are designed for mid-latitue weather. Higher resolution models with equations that are tuned for hurricanes are a much better option, although we still got a long way to go even with those.

 

This is all well known, at least for real tropical cyclone modelers and forecasters. I am just re-iterating what the experts already know.

 

Are you kidding? I'm a tropical meteorologist and heavily use the GFS/ECMWF. The "experts" at the NHC must not be aware of these "facts" either since their discussions mention the GFS and Euro as much, if not more so than any other guidance. If the GFS/EURO are garbage at TCs, then what magical model do you use that is so much better? Please provide those stats when you get a chance.

[BuffaloWeather]

A lot of models have this thing exploding. Are they all out to lunch or what?

 

[WeatherFox]

NOAA Reference, modeling:  http://www.hfip.org/documents/HFIP_AnnualReport_FY2014.pdf

[jojo762]

A lot of models have this thing exploding. Are they all out to lunch or what?

 

Everyone enjoys being negative and ignoring hi-res models that were created specifically for hurricanes/tropical systems I guess. BUT it's still safer to go with what the NHC did on its current track info, just a blend of global and hi-res hurricane models.

[DopplerWx]

00z tracks remain north of hisp.

[WeatherFox]

Everyone enjoys being negative and ignoring hi-res models that were created specifically for hurricanes/tropical systems I guess. BUT it's still safer to go with what the NHC did on its current track info, just a blend of global and hi-res hurricane models.

11PM statement from NHC forecaster is tht he would not be surprised if Erika faces a similar fate that Danny did do to wind shear.

[dtk]

I already said the facts.... global models can barely resolve tropical cyclones, and there's not enough data to initialize with anyways. The equations aren't particularly optmal for tropical forecasting either, they are designed for mid-latitue weather. Higher resolution models with equations that are tuned for hurricanes are a much better option, although we still got a long way to go even with those.

 

This is all well known, at least for real tropical cyclone modelers and forecasters. I am just re-iterating what the experts already know.

No, you're spewing nonsense, for real.  A global model can produce decent QPF forecasts without resolving individual clouds/droplets/etc.  To the TC example, global models are in fact *superior* to higher resolution, hurricane specific models when ti comes to track forecasting.

 

You are right that a global shouldn't be used to attempt to forecast the structure and dynamics of a TC (intensity), but that does not automatically mean they are useless for track forecasting.  What do you think the NHC and JTWC track forecasts are based on?  I'll give you a clue, they rely very heavily on GFS and ECMWF track forecasts.  I guess they don't know what they are doing and have no experience in tropical forecasting.

 

You're kind of out of your league on this one....

[Superstorm93]

Huh, its like I've read this all before... 

 

11pm 

 

The intensity forecast continues to be highly uncertain. Erika
has a large cyclonic envelope, and this is a favorable factor
for the cyclone to strengthen. However, SHIPS model forecasts
a hostile west-northwesterly shear over the cyclone and, in fact, it
only strengthens Erika a little bit at the end of the forecast
period. This coincides with the solution of the GFS and the ECMWF
global models which either weaken the cyclone or show little
change in strength. The NHC forecast follows the intensity
consensus, and shows a modest strengthening beyond 3 days. By then,
the cyclone is expected to be near the Bahamas where the environment
could be a little more favorable for intensification. However, I
will not be a surprised if Erika dissipates like Danny in the
the northeastern Caribbean Sea where the environment is hostile.

 

 

 

[IsentropicLift]

No help on the 00z GFS. It continues to be on the Western side of the latest guidance envelop and and remains an outlier to most guidance.

 

 

That includes its own 18z GEFS ensembles.

 

[andyhb]

I already said the facts.... global models can barely resolve tropical cyclones, and there's not enough data to initialize with anyways. The equations aren't particularly optmal for tropical forecasting either, they are designed for mid-latitue weather. Higher resolution models with equations that are tuned for hurricanes are a much better option, although we still got a long way to go even with those.

 

This is all well known, at least for real tropical cyclone modelers and forecasters. I am just re-iterating what the experts already know.

 

Good to see that absolutely zero has changed with you, standing on a soapbox and all.

 

By experts, are you just referring to yourself? The globals have scored some solid coups with multiple TCs over the past several years. You can't just throw out their data because they aren't showing what you want (which really seems to be what you are doing).

[IsentropicLift]

Is that new blowup over the center? Hard to tell.

 

[NaoPos]

Is that new blowup over the center? Hard to tell.

Diurnal max, so not surprised to see flare ups. Danny did the same thing a few times. Whether or not it can be sustained (not as likely )is the question.

[andyhb]

Everyone enjoys being negative and ignoring hi-res models that were created specifically for hurricanes/tropical systems I guess. BUT it's still safer to go with what the NHC did on its current track info, just a blend of global and hi-res hurricane models.

 

Hi-res models that are often way overzealous and bullish with intensity forecasting.

[wxmx]

I already said the facts.... global models can barely resolve tropical cyclones, and there's not enough data to initialize with anyways. The equations aren't particularly optmal for tropical forecasting either, they are designed for mid-latitue weather. Higher resolution models with equations that are tuned for hurricanes are a much better option, although we still got a long way to go even with those.

 

This is all well known, at least for real tropical cyclone modelers and forecasters. I am just re-iterating what the experts already know.

So you are saying that global models, like the Euro and GFS aren't good for TC forecasting, they are only better than the other global models, and better than current higher resolution hurricane models, but that's all, basically saying they are the best we have now. Ok.

[jojo762]

Is that new blowup over the center? Hard to tell.

it's such a mess... Circulations are no where near vertically stacked, and won't be for quite some time, if ever... And the much of the SE side of the system is void of any convection. Minus that new Blow up of convection, it's looking pretty sketchy. But people will likely be saying it looks like trash for a couple days anyways.

[jojo762]

Hi-res models that are often way overzealous and bullish with intensity forecasting.

Correct. Still can't throw them out entirely though. Just like the NAM when it comes to SVR WX, everybody loves it.

[IsentropicLift]

it's such a mess... Circulations are no where near vertically stacked, and won't be for quite some time, if ever... And the much of the SE side of the system is void of any convection. Minus that new Blow up of convection, it's looking pretty sketchy. But people will likely be saying it looks like trash for a couple days anyways.

It's barely a 35kt storm. Were you expecting a red meat cane? The intensity has been more or less steady since classification. Just a slight weakening trend today but mostly status quo.

[StudentOfClimatology]

That new convective blowup is pretty much right over the LLC or a bit south, but NW of the MLC, I believe.

[jojo762]

It's barely a 35kt storm. Were you expecting a red meat cane? The intensity has been more or less steady since classification. Just a slight weakening trend today but mostly status quo.

did I say I was expecting one? I was just saying its a mess when looking at satellite imagery, very poorly organized, not like it wasn't expected to be amazing at this point.

[cyclone77]

Is that new blowup over the center? Hard to tell.

 

 

Looks a little south of the center here, which is where the white T is located.  (03z fix)

[TropicalAnalystwx13]

Is that new blowup over the center? Hard to tell.

 

Looks to be on the northern edge of that burst near the intersection of 55W 16N to me:

 

[thewxmann]

Everyone enjoys being negative and ignoring hi-res models that were created specifically for hurricanes/tropical systems I guess. BUT it's still safer to go with what the NHC did on its current track info, just a blend of global and hi-res hurricane models.

 

I don't think people are "enjoying" being negative, I think we're being reasonable here. The trends indicate that dissipation is the most likely scenario. As has been mentioned in this thread the globals have tended to outperform the hurricane models.

[negative-nao]

WOW !!!!  THis would crush the Carolinas !!

 

 

http://www.tropicaltidbits.com/analysis/models/gfdl/2015082600/gfdl_mslp_wind_05L_22.png

[andyhb]

WOW !!!!  THis would crush the Carolinas !!

 

 

http://www.tropicaltidbits.com/analysis/models/gfdl/2015082600/gfdl_mslp_wind_05L_22.png

 

There's a certain song by Aerosmith that would ring well right now.

[Stebo]

WOW !!!!  THis would crush the Carolinas !!

 

 

http://www.tropicaltidbits.com/analysis/models/gfdl/2015082600/gfdl_mslp_wind_05L_22.png

Comedy model first off, but secondly it is moving away from the US coast by this point.

[Siker]

Well, the Euro shifted again... To what the HWRF shows (almost, Cat 1 on Euro vs. Cat 2 on HWRF into Miami).