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PSUBlizzicane2007

Tropical Storm Erika

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FWIW the 12z HWRF and GFDL didn't disappoint. 940mb and 930mb respectfully. 

 

926 actually on the GFDL...also big time recurve although I would imagine wave heights on the SE coast would be huge.

 

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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....

Intensity is absolutely crucial to track, and resolving the structure of a tropical cyclone is also crucial. The GFS OP has been completely out to lunch on Erika which just proves my point.

 

I worked for the Hurricane Research Division for 10 years and did hurricane modeling at UW-Madison for 5 years. You sir are the one out of your league. If you wrote this on a test in my class I would fail you.

 

They are very useful for determining large scale patterns, which is a great tool for forecasting, but using them for the track or intensity is quite foolish unless the tropical cyclone is a large and mature hurricane. Erika has been disorganized and the globals can't resolve it.

 

I thought this was a discussion of Erika, I'm not discussing the average statistics of every tropical cyclone in history here. Until Erika is mature global models are garbage.

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GFDL is 100% out to lunch right now, it has it recurving through a high pressure system. GFS map... GFDL takes Erika right through the center of that ridge. I still don't expect a recurve before 80 W, Hispaniola continues to be the main factor. Right now NHC track is awful close to Hispaniola and its going more westerly than expected... so Florida might luck out. Won't know until tomorrow.

 

92fe8e889040ed9263c3167d09a9e60b.png

 

 

If it hits Hispaniola it might even go south of Florida, cause it would be a very weak system.

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I think this may only be a TD now- 1008 on the latest recon fix. South of the official position also. The GFDL is totally bogus IMO, way too strong too early, therefore too far right by a lot on its track. My gut says this stays weak for quite a spell, if it gets stronger, it will be  well to the west in he Bahamas area.

 

EDIT: Euro says no US landfall. Stalls it east of NC. GGEM has a NC hit, UKMET east of the Carolinas at 144.

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Probably one of two scenarios and maybe it's looking more likely that a southern/southwestern fringe-of-the-cone verifies, assuming Erika struggles to maintain organization. If it were to eventually recover, I think we could very well see a sharp recurve out to sea.

 

12z GEFS 1000mb contours:

post-533-0-43426900-1440615667_thumb.gif

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IF...big if...we have a tropical cyclone or a semi-coherent wave, this environment off the SE coast is highly favorable favorable for rather aggressive intensification. The NHC probably will wait two more days to see how Erika deals with the hell its currently enduring before really addressing this 

 

 

 

hwrf-p_shear_05L_33.png

 

ScreenHunter_191%20Aug.%2026%2015.19.png

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IF...big if...we have a tropical cyclone or a semi-coherent wave, this environment off the SE coast is highly favorable favorable for rather aggressive intensification.

Does it really matter? It would be fish food in that case, and I'm still sticking with my original call for dissipation over the Lesser Antilles.

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Intensity is absolutely crucial to track, and resolving the structure of a tropical cyclone is also crucial. The GFS OP has been completely out to lunch on Erika which just proves my point.

 

I worked for the Hurricane Research Division for 10 years and did hurricane modeling at UW-Madison for 5 years. You sir are the one out of your league. If you wrote this on a test in my class I would fail you.

 

They are very useful for determining large scale patterns, which is a great tool for forecasting, but using them for the track or intensity is quite foolish unless the tropical cyclone is a large and mature hurricane. Erika has been disorganized and the globals can't resolve it.

 

I thought this was a discussion of Erika, I'm not discussing the average statistics of every tropical cyclone in history here. Until Erika is mature global models are garbage.

1. You have not proven anything.  You have provided zero evidence to back up anything you have stated thus far.

 

2. I don't need to get into a contest with you over credentials.  I've been doing operational DA and NWP for over a decade now.  I have published peer-reviewed papers specifically about TC initialization for global NWP.

 

3. This is *not* necessarily the case.

 

4. You the one that has been making sweeping generalizations about global models being garbage...first all of the time, but now you seem to have changed your tune.

 

If you want to have a real discussion about issues related to TC DA and NWP, I'm happy to oblige.  

 

p.s. I'm a fellow UW-Madison alum.  It's possible that we actually know (of) each other....

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Why would any focus on operational model forecasts for a tropical cyclone more than five days out? There are some parallels to predicting winter storms. I find the ensembles very useful, especially when an operational model may have wild run to run swings.

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Speaking of NWP...I noticed there is a parallel run of the GFS labeled as "PR4DEV" showing up on the verification charts (and I might add it's doing quite well). The website says this is a 4D-ENKF/VAR experimental version. Anyone have the low-down on it? dtk?

 

By the way, the 00Z run on 8/25 showed Erika intensifying and swinging east past Florida for what it's worth.

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Speaking of NWP...I noticed there is a parallel run of the GFS labeled as "PR4DEV" showing up on the verification charts (and I might add it's doing quite well). The website says this is a 4D-ENKF/VAR experimental version. Anyone have the low-down on it? dtk?

 

By the way, the 00Z run on 8/25 showed Erika intensifying and swinging east past Florida for what it's worth.

What is the link to this page? I would like to take a look myself. Thanks!

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What is the link to this page? I would like to take a look myself. Thanks!

 

http://www.emc.ncep.noaa.gov/gmb/STATS_vsdb/

 

In the 2-D maps section on the right hand side links click the go button next to the 00Z cycle. It seems like it's only the 00Z cycle that has the PR4DEV graphics and for some reason it didn't update with last night's 8/26 run.

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1. You have not proven anything.  You have provided zero evidence to back up anything you have stated thus far.

 

2. I don't need to get into a contest with you over credentials.  I've been doing operational DA and NWP for over a decade now.  I have published peer-reviewed papers specifically about TC initialization for global NWP.

 

3. This is *not* necessarily the case.

 

4. You the one that has been making sweeping generalizations about global models being garbage...first all of the time, but now you seem to have changed your tune.

 

If you want to have a real discussion about issues related to TC DA and NWP, I'm happy to oblige.  

 

p.s. I'm a fellow UW-Madison alum.  It's possible that we actually know (of) each other....

If you want a real discussion then present your arguments, so far your only argument is globals can forecast QPF without microphysics.... which is a terrible example since globals are very inaccurate for qpf due to lack of microphysics.

 

I simply repeated your insult back to you, I was calling the GFS garbage for tropical cyclone forecasting and you took it personally. If you don't like being insulted then maybe you shouldn't insult others.

 

I presented my brief arguments: "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." Prove that any of those statements are wrong instead of throwing red herrings. I could go deeper into it, there are dozens of things in global models that are detrimental to tropical cyclone forecasting, which is the reason hurricane models are being produced.

 

A major problem with the atmospheric science field is people that act like you massively slow down scientific progress by nitpicking ideas and derailing them, while presenting none of their own. There is almost zero progress in government laboratories and even UW-Madison since scientists from other institutions torpedo ideas, so it takes years to publish and then other people have already published it, which is quite inefficient since it wastes money to have many institutions working on the same thing.

 

There is almost always a confrontational stance between meteorologists, where if someone disagrees with something they take it personally and then it becomes a pride thing. And then scientists complain when all their funding gets cut.... that's what happens when you produce nothing and spend all your time ruining other people's projects.

 

This is mostly unrelated to you, this is not a serious scientific debate obviously. What I'm saying is the last thing we need is people demanding hard empirical evidence on a casual discussion board, when the subject being discussed is not fully understood.

 

AMS journals are already in ruins due to similar behavior, no reason to ruin AmericanWX too.

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There is almost always a confrontational stance between meteorologists, where if someone disagrees with something they take it personally and then it becomes a pride thing. And then scientists complain when all their funding gets cut.... that's what happens when you produce nothing and spend all your time ruining other people's projects.

 

The fact that you are typing this sentence baffles me.

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TH, I think you are taking operational models and acting like we are using them verbatim. The op runs are valuable in showing trends and hinting at size or intensity. An op run continuously showing a large and intense TC probably means that conditions may be favorable in the model for intensification. Opposite is also true. They model the global patterns as you stated and therefore inherently should at least try to model the steering pattern of the storm. There is value in the op runs and the stats do show this as DTK pointed out. Of course I would consult TC models and not just globals, but I think you are incorrectly dismissing their value.

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