I'm going to gripe right now

[stormie_skies]

To be fair to the NHC, I don't think anybody predicted - or likely could have predicted - the extreme fluctuations Miss Em has given us in the last 48 hours. To go from a Cat 1 to a Cat 4 in 24 hours, then weaken nearly to a Cat 1 again and fight back to become nearly a Cat 5 in another 24 hours....and all without land contact to initiate such extreme fluctuations.... I guess I'm reluctant to give anyone slack about not seeing that. If anyone else, here or elsewhere, predicted those fluctuations accurately....I'd really love to have a link.

That said, I do think Avila was way to quick to downplay Em yesterday...which I stated at the time. To say that there would be no strengthening in the Gulf, and to drop her back down to a "generous" low two based on a sattelite presentation many thought was improving and without recent recon info seemed a bit hasty to me.... when dealing with intensity, I would always rather see people be prepared for a strong storm if the potential is there, and if the storm weakens, at least everyone is safe. But hey - I'm not a met, perhaps he saw something that I didn't, I'm certainly not gonna get into a forecasting match with him!

[Windy]

The NHC is FORECASTING. They admit their errors and faults, they are human. Boy I wish I could get through a day without any errors. Please don't be so critical of the NHC. A forecast is not set in stone as I believe some here think it should be. I personally have 100% trust in the NHC. Kudos to them! Keep up the good work guys (and gals!)

You're erroneously assuming that we don't undestand what a forecast is... don't be patronizing. I well understand the methodology and philosophy of a forecast. But a forecast must be reasonably accurate within some margin of error some reasonable percentage of the time to be useful. I think the long-range intensity forecasts (From ANYONE, not just the NHC) do not meet this usefulness. 72 hours from now, the NHC freely admits that it can't really pin down whether Emily is going to be a strong CAT 3 or a tropical storm, but if you look at their official intensity forecast, it says "105KT" with no qualifiers or disclaimer.

You can't just say "It's a forecast!" One could theoretically attempt to forecast the temperature and percent chance of rain for Chicago three years from now -- but just because it is a forecast does not mean that it is useful or that it does more good than harm.

[tailgater]

IF YOU DON'T LIKE THE FORECAST FROM NHC/TPC DON"T USE IT. You can always use your gut feeling or accu wx but please stop the BITC*ing, they are doing the best they can and are improving.

[cccmachine]

NHC missed Ivan's track big time last year.
There was a poster by the name of Gomez that nailed his track 5 days out but his post was unfortunately deleated.

[Windy]

IF YOU DON'T LIKE THE FORECAST FROM NHC/TPC DON"T USE IT. You can always use your gut feeling or accu wx but please stop the BITC*ing, they are doing the best they can and are improving.

You aren't being particularly useful, here. This isn't whiney-Janing going on here. This is presented as a valid observation. If it's not a valid observation, then by all means explain why, but don't be a fanboy. The NHC team are rational, dispassionate forecasters and have no problem with discussing forecast verification and usefulness. I almost wish one of them where here to explain forcast rationalization on intensity; no doubt they'd probably be pretty convincing.

[vbhoutex]

It's true that the NHC freely admits that it's intensity forecasts are subject to wide error. I guess to me the question is: why publish a number if it's probably going to be wrong? At some point publishing a number becomes misinformation. The public at large doesn't understand anything about the wide gulf between forecast and reality when it comes to intensityy... all they see is the number.

Let's presume I am some "normal" American with a hurricane bearing down on me. I would like to know what intensity of winds I need to prepare for. It does make a difference in the preparation needed if one is preparing for 150 mph winds vs 75 mph winds. Admittedly both can do enough damage, but I'm not too sure most "normal" Americans would board up for a CAT1 storm.

[Windy]

It's true that the NHC freely admits that it's intensity forecasts are subject to wide error. I guess to me the question is: why publish a number if it's probably going to be wrong? At some point publishing a number becomes misinformation. The public at large doesn't understand anything about the wide gulf between forecast and reality when it comes to intensityy... all they see is the number.

Let's presume I am some "normal" American with a hurricane bearing down on me. I would like to know what intensity of winds I need to prepare for. It does make a difference in the preparation needed if one is preparing for 150 mph winds vs 75 mph winds. Admittedly both can do enough damage, but I'm not too sure most "normal" Americans would board up for a CAT1 storm.

You're missing the point. Yes, that's useful information to have. It's not useful, however, if the provided information is not likely to be accurate. In fact, sometimes the information has a potential to be profoundly dangerous if it dramatically underforecasts intentisty.

I know the NHC does forecast verification for this type of stuff. They know they're not batting too well -- you can see this from the wide margin on the probability charts. This does not mean that they suck -- this just means that intensity forecasting is probably much more suceptible to chaotic output than track forecasting. But the text products either need to be more upfront about this or drop the intensity figures beyond 24 hours altogether, IMO.

[rtd2]

I think that the NHC has been pretty up front about the problems with intensity forecasts, but on the other hand, there track forecasts have by in large been pretty impressive. That puts the responsibility on us to take appropriate action if we are in the projected track.

Thats my thoughts as well NHC has NEVER claimed to have solved the intensity part of forecasting ...The track and error of margin HAS reduced in thelast several years and the NHC HAS IMHO Zoned in on the tracks to a near PERFECT accuracy and that to me is the MOST Impressive aspect of these storms

[AL Chili Pepper]

So far the NHC has nailed the track.

They did a great job with Dennis too.

Intensity is another topic. It's just so hard to predict, especially with ERC's, etc. They admit that freely. I'm sure over the years it will get better.

Let's all be careful/mindful not to get too spoiled with the accuracy of the track forecast.

I'm sure a lot of us feel your frustration here but we can't really blame the NHC; they do the best job they can with what we have.

Not perfect on track!!! They never forecasted it to go through central Cuba for 18 hours then weaken to a cat1!!!

Then they where forecasting Mobile up intill the last hour or so. With a small storm like dennis that is huge.

The NHC will readily admit that they have a problem when it comes to forecasting intensity. That being said, they did an excellent job on their projected path of Dennis.

[tailgater]

IF YOU DON'T LIKE THE FORECAST FROM NHC/TPC DON"T USE IT. You can always use your gut feeling or accu wx but please stop the BITC*ing, they are doing the best they can and are improving.

You aren't being particularly useful, here. This isn't whiney-Janing going on here. This is presented as a valid observation. If it's not a valid observation, then by all means explain why, but don't be a fanboy. The NHC team are rational, dispassionate forecasters and have no problem with discussing forecast verification and usefulness. I almost wish one of them where here to explain forcast rationalization on intensity; no doubt they'd probably be pretty convincing.

This is a tiny storm in size, meaning it's very susceptible to the slightest environmental changes such as: ULL to it's west, dry air, SRENTGH of ridge to it's north, South America' s inflow disruption.speed of T.C. and even timing of EWRC's. The original poster says GRIPE

[feederband]

Come on there is no way ever EVER are they going to be perfect on these tropical weather events...They just do the best they can with what they have and the coastal states owe them a debt of gratitude .There is always room for improvement and I think they have showed it year after year...

[Swimdude]

I hate to make a generalization, but i've noticed that with about 90% of storms, the NHC predicts LOWER intensity than what it eventually becomes. So I agree with the original statements made. The directional forecast is improving drastically by the NHC, but the intensity forecast is still quite sub-par.

[wxman57]

Let's presume I am some "normal" American with a hurricane bearing down on me. I would like to know what intensity of winds I need to prepare for. It does make a difference in the preparation needed if one is preparing for 150 mph winds vs 75 mph winds. Admittedly both can do enough damage, but I'm not too sure most "normal" Americans would board up for a CAT1 storm.

Not to pick on you, vbhoutex, as this applies to everyone here...

I think that Emily is proving that you'd darn sure better board up (or leave if you're in a surge zone) for ANY hurricane that approaches, even a strong tropical storm. Unless you can forecast intensity better than the models or the NHC, then how can you be sure that Cat 1 in the Gulf at 3pm one afternoon won't be a Cat 4/5 bearing down on Galveston the next afternoon? You just can't! Now there are cases where we can identify strong wind shear along the coast that will definitely weaken a storm prior to landfall. But without such a strong indication of wind shear, you need to treat every single tropical cyclone like it can become a major hurricane in 24 hours, particularly in the NW Caribbean or Gulf of Mexico.

That's why I have such a gripe about those who say they'll ride out a Cat 1-2 but leave for a 3-4-5. That kind of thinking assumes we mets have some kind of skill in forecasting intensity. Clearly, without more data, we're clueless when it comes to forecasting intensity much of the time. Are any of you better at forecasting intensity?

[NC George]

I hate to make a generalization, but i've noticed that with about 90% of storms, the NHC predicts LOWER intensity than what it eventually becomes. So I agree with the original statements made. The directional forecast is improving drastically by the NHC, but the intensity forecast is still quite sub-par.

I would generalize in the other direction. I think the NHC typically overestimates intensity at landfall, which leads people to believe storms aren't going to be as bad as they are 'advertising.' Then, when a Charley comes along, everyone is surprised because it is much worse than expected.

Three ideas on why is happens:

(1) Using flight level winds to estimate ground wind speed: I would say the multiplier is more like .85 or .8 than .9. I say this because landfalling windspeeds never seem to match up to RECON observations made just an hour or so before landfall. Excuses are always given than either the max winds didn't reach an observation location, or that the land interfered with the strongest winds, and they didn't make it all the way to the ground. I say if we are measuring surface speed and the winds don't make it to the surface then they don't count.

(2) Radar/Satellite presentation: I think we overestimate the visual appearance by a catagory. Right now, people are stating that Emily 'looks like' a category 5. Maybe that's what a solid Cat 4 looks like. We only know what category is is by what the RECON tells us, and then we are estimating windspeed (perhaps too high, as per item 1.) When we say, 'that looks like a Cat 3,' maybe that just what a good Cat 2 looks like.

(3) Don't we use 1 minute averages, rather than the 5-10 minute averages the rest of the world uses? Maybe it's time to think about joining the rest of the world, if only for consistancy.

Why this is important: The price of gasoline shot up 20 cents, all over the country, all based on a forecast of a Cat 4/5 moving through the gulf oil region. How much do you think that forecast cost (is still costing) the United States?

[Derek Ortt]

the max winds are not at the surface, but at 10m. many of the home obs aren't at the proper elevation and the gov't sites are far to spread out

[beachbum_al]

I agree! One of the reason why if you are in area that might be hit by a hurricane you need to take preparations. These storms have a mind of their own. They go where they want. Well with a little help from high pressures, etc.

[MWatkins]

You've been superb on track forecasting, but unless you can get better on intensity, I think you should treat all hurricanes as extremely dangerous.

If you can explain to me why Emily exploded to above 105 knots I'll be willing to listen, but I won't be particularly comforted by your explanation if you also tell me that it is a rare event.

The NHC is very up front with the idea that there is considerable uncertainty with intensity forecasting. Intensity prediction has not improved at all vs. the 10 year average error rate...and no dynamical model can even beat a simple statistical model. I know you know this.

Throw in the fact that the NHC also produces probabilistic forecast products to better handle the potential error...and the fact that they have been indicating their intensity forecasts may have been conservate and more strengthening was likely. Looks like you are focusing the one thing that the NHC has asked folks not to do over and over again...on the deterministic forecast intensity values at the bottom of the discussion instead of the entire range of products available for the public to consider.



Also...they have as much experience as I do, you do, and my 6 year old son has with a major hurricane traversing the western Caribbean in the middle of July. none. I am sure this has also given them pause to forecast a cat 4/5.

Finally...the notion that a 105 knot storm is not a significant and potentially dangerous event is flawed as well. Especially for the vast majority of structures along the forecast path.

MW

[beachbum_al]

You know I just realize I read that wrong. I am not sure what the answer is.

[otowntiger]

Well I've got to admit that I was wrong. I thought Emily had peaked already and here she goes again. I agree with you Sooner in that the NHC has got a long way to go to get any kind of handle on intensity forecasts. It is my opinion that if they get the track right but blow it big time on the the intensity, then they are only 50% successful. If they accurately predict the path but tell us a storm will be only a cat 1 when it slams the coast the next day as a cat 3, the ramifications would be huge. The difference would be night and day.

[Tri-State_1925]

The NHC did a pretty good job with tracks last year, I'll give them credit. Obviously intensity is a problem...they can't handle intensity at this stage.

I haven't been following this storm very closely yet. I heard a report on TV the other day that it was only going to be around cat 2, so I'm shocked to suddenly see these reports of a 145 mph storm passing by Jamaica.