If it does make landfall, What is projected strength?

[slosh]

To me it looks like the models have a hard time forecasting Isabel's strength. Why have the intensity estimates been off and provided this storm makes landfall in the NC / VA, what would be the intensity?

[Josephine96]

If the storm gets picked up by a cold front/ trough.. it may weaken a great deal or just a bit.. plus up in that area.. even with the Gulf stream near by.. because the storm is moving so fast.. it would weaken it a little..

Just my opinion...

[slosh]

Is it correct to assume that the further north it makes landfall, the weaker she will be, because of the trough and sst's?

[Josephine96]

Yes slosh.. that is correct...

[Stormsfury]

Slosh, intensity forecasts are the absolute hardest things to forecast in regards to tropical cyclones. The SST's themselves will not be an issued until past 35ºN, but some southwesterly shear is progged at the end of the period and that would play a factor in weakening Isabel.

SF

[Josephine96]

Storms Fury- Thank you for elaborating a little.. I thought it was a simple yes or no answer lol.. But thank you..

[slosh]

Thanks Stormsfury

[wxman57]

Forecasting a storm's intensit is tremendously more difficult than forecasting its path. And we know how hard it can be to forecast a track correctly. Our ability to forecast hurricane intensity has not improved significantly in the last 2-3 decades. Average forecast errors are about 20-30 mph per 24 hours. That's A LOT!

Now there's a good reason for such errors. While it is very important to know the initial conditions surrounding a storm and well upstream along its path in order for the thermodynamic equations to have much success in predicting the track, it is even MORE important to know these initial conditions when forecasting intensity. Hurricanes are VERY delicate structures, believe it or not. Just the slightest change in upper-level winds can result in a Cat 4 becoming a Cat 1 in 12 hours (remember Lili last year). But such slight changes may not affect a storm's track that much.

But consider that out there in the tropics we know VERY LITTLE about what is actually happening in the environment surrounding a storm. Certainly, we don't know enough detail to accurately predict such minor variations in upper-level wind/moisture conditions. And we won't have such data for quite a number of years from now.

Hope is on the horizon, however. The next generation of satellites will have significant "remote sounding" capabilities. These satellites will be capable of looking down at grid points across the ocean and measuring winds, temperatures, and moisture from the top of the troposphere down to the ocean surface. In theory, these data could be input into computer models to help initialize them better, thus producing much more accurate forecasts of both intensity and track. I say "in theory" because some satellites already have such capabilities, but with insuficient funding and manpower, these data are generally left out of model runs.

[hurricanedude]

I say at least a strong cat 3 in the NC/VA border area, that sound resonable??

[weatherluvr]

Forward speed will also be a very important factor if it goes farther up the coast, as it would decrease the amount of time over cooler SST's and it would increase the wind speed on the right side. So even if it does weaken to a cat 1 or 2, the right side would have the forward speed momentum as well.

[slosh]

Does forward speed momentum add to surface wind speed estimates?

[Steve Cosby]

Does forward speed momentum add to surface wind speed estimates?

Ah, the other great debate!

When Fabian hit Bermuda, there was record of winds. I forget the exact numbers but the aircraft recon set the wind speed at a certain level that was proven by the on-ground instruments in the right quadrant of the hurricane. There was not an extra 15-20 KTS added on.

So, the answer to your question, is no with proof coming from this recent experience.

That said, there seems to continue to be great debate on this subject even though Fabian seemed to debunk the theory.

[Guest]

said N/C & NJ a direct hit. I think Isabel will be a cat. 4 hurricane when making landfall because of the warm water. Their (Meterologists) saying Isabel will not weaken any until landfall. Anyone living on the eastcoast should monitor Isabel which is now a dangerous hurricane. Time to get prepared and I know the grocery stores next week are going to be hectic as this hurricane approaches.

[JetMaxx]

The record storm for the Cape Hatteras and Virginia Beach area was the severe hurricane of September 1944....sustained winds of 130 mph (the anemometer at Cape Hatteras failed at 110 mph; a peak gust of 150 mph was measured at Cape Henry, Virginia).

A 140 mph hurricane is climatologically possible on the Carolina outer banks. The great September 1938 hurricane was estimated to be 940 mb and 140 mph as it passed about 75 miles east of Cape Hatteras (and still a 125-130 mph cat 3 at landfall on central Long Island, NY). Several other hurricanes have sustained winds of 140 mph at the same latitude (35 N) as Cape Hatteras is located.

Hurricane Isabel is the same type of hurricane as both the 1938 and 1944 hurricanes were...large and intense with a large eye; so a 130-140 mph hurricane at landfall won't surprise me.

[HurricaneQueen]

The SST off the east coast have been at near record lows all summer so if Isable slows any on her way to landfall in northeast, in my opinion, she should lose significant energy. Just a novice opinion but I know that the waters have been extremely cool of the coast of say NJ all summer.

[Guest]

I was listneing to steve lyons and he said Isabel will be a dangerous hurricane when making landfall. From what I was reading in the 11:00 am discussion Isabel is not going to weaken any until land fall and may intensify over the warm waters slightly. I'm saying a cat 4 or no less then a cat. 3 at the time of landfall. Warm waters is the hurricanes fuel to stay strong.