Gulf Power's Wind Gauge in Ivan.........

[Derek Ortt]

Hurricanebill,

you have a very valid point about the need for a new classification system as the current one is wind only. In fact, with the re-analysis, Gloria will likely now be a cat 2 at Hatteras and only a cat 1 now at Long Island. Many of the "major" hurricanes from the 50's will likely now be 1's and 2's at landfall. Regarding Gloria, the new peak intensity may be as low as 105-115KT based upon the maximum 850 or 700mb wind data.

However, in the mean time, the only thing that determines the SS category is wind and wind alone; thus, that is why Ivan was likely a borderline 2/3 at landfall. Also, the surge values given in the SS scale apply only to the Miami area (to the south, they are too high as was shown in Andrew and in the GOM, they are way low and are about 50% higher than those given in the table)

[Derek Ortt]

Hurrmike,

The SFMR data from NOAA recon also indicated 95KT at the time of landfall, just below the thresshold of a cat 3. The surface obs were consistent with the recon findings (well, at least the one at Pensacola)

[iceangel]

All I have to say on this subject anymore is,,,I know what I went through, I know the winds were real high where I am, I know they NEVER decreased, and I know our neighborhood looked like a war zone the next day!

nuff said!

[HurricaneBill]

Hurricanebill,

you have a very valid point about the need for a new classification system as the current one is wind only. In fact, with the re-analysis, Gloria will likely now be a cat 2 at Hatteras and only a cat 1 now at Long Island. Many of the "major" hurricanes from the 50's will likely now be 1's and 2's at landfall. Regarding Gloria, the new peak intensity may be as low as 105-115KT based upon the maximum 850 or 700mb wind data.

However, in the mean time, the only thing that determines the SS category is wind and wind alone; thus, that is why Ivan was likely a borderline 2/3 at landfall. Also, the surge values given in the SS scale apply only to the Miami area (to the south, they are too high as was shown in Andrew and in the GOM, they are way low and are about 50% higher than those given in the table)

But didn't Gloria have a pressure of 920mb at peak intensity?

Also, just out of curiosity, it seems like the re-analysis is downgrading all the storms. Any upgrades? (Besides Andrew?)

[Derek Ortt]

the indianiola hurricane of texas in the 1800's was increased to 135KT.

There have been about as many upgrades as downgrades, especially in the earlier landfalls

[Derek Ortt]

ftp://ftp.nhc.noaa.gov/pub/storm_archiv ... elim02.gif

based upon this data, the maximum winds of gloria were 110-115KT, upper cat 3 at peak intensity

[Derecho]

People seem to have a consistently inflated notion of the strongest winds they've experienced, and are pretty terrible at "eyeball" estimates of winds.

I remember on the old Storm2K chat a contingent of folks from the USVI that were convinced Marilyn was a Category 5 and that there was a massive coverup by NHC.

The other problem seems to be a weird attitude that anything below Category 3 shouldn't be capable of causing any damage. (Same goes for svr wx, ANY wind damage at all causes people to insist "tornado" in ALL instances.)

[Stormsfury]

3. Pensacola had not seen cat 2 winds since 1926, so how would anyone know just how bad sustained cat 2 winds in the city are. Most were not born or living in the city during the 1926 hurricane (same one that devastated Miami). Much of the WIND damage appears similar to that of Fran in Wilmington. A strong 3 or 4 would do a lot more than blow out walls.

What is really irking me is the level of complaciency after Ivan. Just like downtown Charleston thinks they went through a cat 4 in Hugo (when they got a strong 2). Pensacola thinks they went through a 4, when they also got a 2 (any cat 3 winds were likely in extreme western Florida or Alabama). People are going to make the mistake the next time a 3 comes, thinking they can survive that, only to find out that if it makes a direct hit on the city, it is going to be 10 times worse than Ivan

Outstanding point, here ... (in highlighted bold text) ... people STILL to this day believe that Hugo was CAT 4 in Charleston and some even want to INFLATE the wind speeds, when in actuality, the winds were high-end CAT 2 (sustained) ... amazingly enough, the CHS WFO (located in North Charleston) highest PEAK gust was 98 MPH ... Sumter, SC, located farther inland was MUCH stronger than that, 110 MPH ...

Areas NE of Charleston ... places like Awendaw, Bulls Bay, and especially McClellanville, SC received the CAT 4 winds, and barely ANYTHING stood ... the land was basically stripped barren ...

This is what a CAT 4 looks like ... with storm surge (Ivan's built up surge with very similar from it's time as a CAT 4/5) ...


This picture was taken from the Francis Marion National Forest (which USED to be densely laden with trees for miles around ... and was reduced to timbers) a bit inland from the coast (no storm surge factor) ....


This is the NHC wind profile chart (seen below) ... interesting profile, with the strong core WEST and NW of Charleston ... yep, that's exactly where I'm at ... right in the bullseye ... 110 MPH winds were HOWLING continuously for hours, BUT while many, many structures were destroyed, and/or heavily damaged, a good majority still stood ... and I PREVIOUSLY estimated that the winds were higher ... they just HAD to be. But once you get past a certain threshold of winds, estimations alone aren't enough, and will ALWAYS be overestimated ... I've seen it time and time again from the amateur to the professional NWS meteorologists ...

In Awendaw, McClellanville, and in Berkeley County (Francis Marion National Forest) ... 90%-95% of the structures were DESTROYED, and the heavily laden forest was flattened ... structured torn to shreds ... I have tons of pictures, but no scanner to upload ... I can't stress this enough for Charlestonians, in particular ... the strongest core of winds were well NE of Charleston, and with Ivan, appears to be in between Gulf Shores, and Pensacola ... in fact, Hugo and Ivan have a lot of striking similarities in regards to large wind fields and relatively fast motion inland, producing far reaching WIND damage effects far inland. Ivan was moving a bit slower than Hugo, but the areas NE and E of the actual eye (stuck in the eyewall) had to endure damaging winds for around 6-8 hours (twice as long as the strongest core of winds in Charleston, and even in Awendaw, which lasted about 4-5 hours) ...

IMHO, Ivan was a low-end CAT 3 (120 MPH) at landfall, but the MAJORITY of that core was still on the southern eyewall at the time of landfall and offshore, with a very-narrow core of 115-120 MPH in the NE/E Quad ... all the wind gauges failed to report the strongest core of winds, either b/c of pwoer failures and/or the core did not cross where a anemometer was located ...

After this season, the validity of HurricaneBill's proposal of rating a storm based on wind, rainfall, AND surge becomes increasingly better and better every day ... A hurricane JUST isn't a windmaker ...

[Derek Ortt]

excellent post, sf

that is a great wind map, showing just how small of an area receives the very strong winds, while most of the region receives a cat 1 or 2 hurricane, even in a landfalling cat 4 storm. However, the winds in a cat 1 or 2 are equivalent to those in an F-1 tornado, which can still cause significant damage, while the winds in a 3 or 4 are of an F-2 tornado

[iceangel]

Floyd,
The 1926 hurricane (same one that devastated Miami).

http://www.pensacolanewsjournal.com/new ... ane1.shtml

I had to respond just one more time....now...

nuff said

[Scorpion]

I totally agree with all of this. I am definitely guilty of overestimating winds. During Frances, when I was outside in the "eyewall" if you can call it that, I estimated winds to be sustained at 85-90 with gusts to 100. In reality, it is likely the winds were 60-65 with gusts to around 75. Everyone here thinks we can get through any hurricane fine, because we just went through 2. But when a true Cat 3 comes barrelling right at us, theres going to be alot more damage.

[HurricaneBill]

OK, I think I'm beginning to figure out what the problem is here.

The general public probably sees a hurricane like this dartboard.



Let's pretend the dartboard is a Category 3 hurricane.

People probably think that the dark blue area will experience tropical storm force winds. The light blue area will get Category 1 winds. The outer green area will get Category 2 winds. The inner green area will get Category 3 winds. The red area is the eye.

Of course, this does make sense to some extent. However, hurricane winds do not increase in equal layered rings as you move closer to the center.

Let's say Derek is 10 miles NE of the eye. Floydbuster is 10 miles SE of the eye. Stormsfury is 10 miles SW of the eye. I'm 10 miles NW of the eye.

This is what many probably think:
We are all equal distances from the eye. We should all experience winds of equal force, right?

Wrong. Derek will probably get the highest winds while I'll probably get the weakest. All 4 of us would get different wind readings.

[Normandy]

But when a true Cat 3 comes barrelling right at us, theres going to be alot more damage.

Jeanne was a true cat 3. I still havn't seen damage from Jeanne that is even near the level as damage from Ivan (Wind and surge). That is why I am skeptical of Ivan being a Cat-2.

[Derek Ortt]

where are you located, normandy?

if you were not in a narrow swath, you did not receive cat 3 winds from Jeanne. Only Hutichinson Island and areas immediately to the west along the immediate coastline received the cat 3 winds.

also, a cat 5 hurricane would produce the same surge as does a cat 2/3 in the GOM along the EC of Florida

[Normandy]

Derek, i live in Houston.

[Scorpion]

Yeah, I meant that Palm Beach County didn't get Cat 3 conditions. I went up to Hutchinson Island a few weeks ago and the damage was pretty bad. Easily winds of 125-130. But, the damage from Ivan in Pensacola looks as bad or even worse.

[Derek Ortt]

the ceter of PB likely received minimal cat 1 conditions, with extreme northern Palm Beach through vero Beach receiving category two conditions in the southern eye wall.

The worst came in from Hutchinson through melbourne, though I doubt that Melbourne received cat 3 winds, likely cat 2 there as well. Winds likely were 110KT with Jeanne at landfall at Hutchinson, and then decreased to below cat 3 intensity within 3-5 miles of the coast on the mainland

[MGC]

Having just driven through most of Florida (except where Charlie made landfall) the wind and water damage in the Pensacola area seemed to be by far the worst I observed.......MGC

[Anonymous]

OK, I think I'm beginning to figure out what the problem is here.

The general public probably sees a hurricane like this dartboard.



Let's pretend the dartboard is a Category 3 hurricane.

People probably think that the dark blue area will experience tropical storm force winds. The light blue area will get Category 1 winds. The outer green area will get Category 2 winds. The inner green area will get Category 3 winds. The red area is the eye.

Of course, this does make sense to some extent. However, hurricane winds do not increase in equal layered rings as you move closer to the center.

Let's say Derek is 10 miles NE of the eye. Floydbuster is 10 miles SE of the eye. Stormsfury is 10 miles SW of the eye. I'm 10 miles NW of the eye.

This is what many probably think:
We are all equal distances from the eye. We should all experience winds of equal force, right?

Wrong. Derek will probably get the highest winds while I'll probably get the weakest. All 4 of us would get different wind readings.

One must note that this would be true with Ivan but not all hurricanes... With Frances and Jeanne, It would have been you who saw the worst winds due to direction of movement and the right front quadrant changes with a west moving hurricane vs a Northeast moving hurricane--many people say its always the northeast quadrant that is the worst but it is different with each storm but Northeast side is almost always true in the Northeastern Gulf. Just my 2 cents

[birdwomn]

People seem to have a consistently inflated notion of the strongest winds they've experienced, and are pretty terrible at "eyeball" estimates of winds.

Interesting comment about "eyeball estimates". One of the things my sister said about going thru Ivan is that the pressure got so bad at times that if felt like her eyeballs were going to pop out.

I also have a big concern about people feeling as if they can make it thru a major hurricane. Not so much the people in Pensacola, I think they have seen enough storms to have respect for them, overall. But people here in the Tampa Bay area, I am not so sure about.