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The Inland Wind Model and the Maximum Envelope Of Winds

Posted: Sun Jun 10, 2012 11:12 pm
by Ptarmigan
The Inland Wind Model and the Maximum Envelope Of Winds
http://www.nhc.noaa.gov/aboutmeow.shtml

How strong would a hurricane be inland based on Category from 1 to 5. If Houston area saw a Category 5 hurricane moving at 8 knots, Houston would see Category 1 to 2 winds. Winds tend to drop off inland. I consider gusts more dangerous than sustained winds. For example, if an area has sustained winds of 100 mph, gusts can go as high as 140 mph. Gusts is usually what does the damage.

Re: The Inland Wind Model and the Maximum Envelope Of Winds

Posted: Sun Jul 01, 2012 3:55 pm
by TexasMetBlake
I totally disagree with that. If a Cat. 5 hit the Houston/Galveston area head on, you would have Cat. 3/4 winds reach the City of Houston. Ike was a cat. 2 and sustained winds of hurricane force were recorded at Hobby. Since the picture is cut off, the yellow contour represents 74 mph or greater. The orange that extends well inland into Liberty, San Jacinto and Polk counties is 85+.

http://www.atmo.ttu.edu/TTUHRT/HwindSwath.png

Image

Here's another example from Hurricane Charley (top end Cat. 4). The motion of the hurricane was SW to NE. The trek across Florida was 120 miles or more. SUSTAINED hurricane force winds made it all the way across the peninsula.
Image

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Re: The Inland Wind Model and the Maximum Envelope Of Winds

Posted: Sun Jul 01, 2012 5:21 pm
by Ptarmigan
Candy Cane wrote:I totally disagree with that. If a Cat. 5 hit the Houston/Galveston area head on, you would have Cat. 3/4 winds reach the City of Houston. Ike was a cat. 2 and sustained winds of hurricane force were recorded at Hobby. Since the picture is cut off, the yellow contour represents 74 mph or greater. The orange that extends well inland into Liberty, San Jacinto and Polk counties is 85+.

http://www.atmo.ttu.edu/TTUHRT/HwindSwath.png

http://www.atmo.ttu.edu/TTUHRT/HwindSwath.png

Here's another example from Hurricane Charley (top end Cat. 4). The motion of the hurricane was SW to NE. The trek across Florida was 120 miles or more. SUSTAINED hurricane force winds made it all the way across the peninsula.
http://www.srh.noaa.gov/images/mlb/surv ... FW_CWA.png

http://www.srh.noaa.gov/images/mlb/surv ... dswath.jpg
No doubt about it. I think the NOAA based it on computer models or something like that. I do recall reading that if a Category 5 hurricane hit Houston area, there would be sustained winds of 120 to 150 mph and that would be really bad. :shock: :o

I am pretty sure Houston has received Category +3 force winds from past hurricanes.
http://forums.khou.com/viewtopic.php?f=4&t=138&p=4007

Re: The Inland Wind Model and the Maximum Envelope Of Winds

Posted: Sun Jul 01, 2012 9:02 pm
by wxman57
Actually, Charley's sustained hurricane force winds only made it half way across the Peninsula (about 100 miles) to south of Orlando. That Charley max wind graphic above is just that - max wind (gusts), not max sustained wind (1 min avg):

http://www.aoml.noaa.gov/hrd/Storm_page ... fl_mph.pdf

Much depends on the state of the hurricane at landfall - is it intensifying (as Ike was) or weakening (like Rita). An intensifying hurricane will carry its hurricane force winds inland for a greater distance.

That said, a 160-170 mph hurricane striking south of Houston would probably produce 110-120 mph wind into central Houston, possibly more. Of course, that depends also on its forward speed. A faster moving hurricane would carry its winds farther inland.

Re: The Inland Wind Model and the Maximum Envelope Of Winds

Posted: Mon Jul 02, 2012 7:30 am
by wxman57
Found the link to the inland wind decay charts:

http://www.nhc.noaa.gov/aboutmeow.shtml

One thing to keep in mind about hurricanes is that every single one is different as far as its wind structure. You could have one Cat 4 hurricane with 145 mph wind over a few square miles in the NE quadrant and winds in the other three quadrants all in Cat 1 range. Or you could have a Cat 4 hurricane (145 mph peak winds again) with widespread Cat 3-4 winds over thousands of square miles in all 4 quadrants.

While each appears identical on the Saffir-Simpson Hurricane Wind Scale, each would produce markedly different winds over land.