High-Res Satellite & Surface Obversation Plots

[wxman57]

Here's the latest of Isabel at landfall. I say at landfall because for all practical purposes, Isabel made landfall over an hour ago if you consider the landfall of maximum winds near the eye.

http://home.houston.rr.com/wx/isabel61.gif

So far, the maximum sustained wind that has been measured has been about 80 mph with gusts to 98 mph. That's minimal Cat 1 so far. Remember, the NHC has been overstating the maximum winds in Isabel for days. This is most likely not a Cat 2 storm. Max winds are probably in the 85-90 mph range in a very small area offshore. That's pretty close to Cat 2, though. Still, 85-90 mph wind with gusts over 100 mph is pretty strong.

[Anonymous]

Isabel IS a Cat 2 storm according to the NHC. The pressure is 956mb which is well within Cat 2 range. The NHC has not been overselling it as a Cat 2 -- instead you have been consistently trying to convince everyone to underestimate it for the past couple days. Isabel did not make landfall an hour ago. Isabel will have a wide impact on the region because of the very strong winds aloft as the NHC explained in the last discussion. Calling it a Cat 1 would be underestimating this potential threat.

[Wolfman21]

jesus christ, who cares about 10 mph? i mean really, it doesnt make THAT big of a difference

[wxman57]

Actually, the NHC has been consistently overstating the winds. See for yourself:

http://www.aoml.noaa.gov/hrd/Storm_page ... /wind.html

Here's a graphic from late last night:
ftp://ftp.aoml.noaa.gov/pub/hrd/hwind/2 ... ol4deg.png
(note only 65-70 kts in western half of storm, and the small area of 80 kt winds right of the center. <b> Also note the NHC was calling it a 95 kt storm at the time</b>).

Generally, the NHC has been stating the winds as 5-10 kts higher than those being observed by NOAA dropwindsondes. You're seeing only a tiny bit of the observations from the recon planes.

Isabel is not a typically-structured storm. Yes, it has a pressure that would suggest a Cat 2 strength, but the vertical wind profile is quite atypical of a "normal" hurricane. I.E., flight level winds are MUCH higher than surface winds. Isabel is sort of like Bonnie in 1998. Recon measured 140 kt winds at 1500 feet above the ground in Bonnie, but only 80 kts at the surface. So while Isabel's pressure supports Cat 2, current surface winds are probably not quite there. And then, any wind approaching 90 mph sustained (as you can see from the HRD graphics above) is only in a very small part of the storm.

As for landfall, I clearly stated that I defined landfall as being the movement ashore of the strongest squalls. I think you can see from the TV reports that they have hit the coast over an hour ago. It makes no difference that the center is going to move ashore in an hour or so, as it is very broad with weaker winds than have already moved inland. The back side of the center has some pretty good squalls, though.

Now I'm certainly not saying that Isabel isn't dangerous. I can see the reports on TWC of hurricane-force winds. And even if sustained 1-minute winds are not really near 100 mph, gusts of 100-120 mph are quite likely. But I want it to be clear that Isabel is NOWHERE NEAR a major Category 3 hurricane in intensity, as many had been forecasting for landfall. East coast residents were very lucky that cool, dry air was entrained into the storm, preventing intensfication.

[wxman57]

jesus christ, who cares about 10 mph? i mean really, it doesnt make THAT big of a difference

Correct, it really doesn't. Just a technicality.