CFHC Talkback For News Story #29:
Newest Talkback: 09:48 PM 05-22 EDT

HAW: High Winds and Tornadoes
09:04 AM EDT - 22 May 2001

Today in Hurricane Awareness week the spotlight is on high winds and tornadoes. This is a good time to go over the Saffir-Simpson Hurricane Scale.

Category Windspeed & Pressure Effects/Example

1

74-95 mph

>980 MB

 Damage primarily to unanchored mobile homes, shrubbery, and trees. Also, some coastal road flooding and minor pier damage.
Example: Hurricane Erin (1995)

2

96-110 mph

965-679 MB

 Some roofing material, door, and window damage to buildings. Considerable damage to vegetation, mobile homes, and piers. Coastal and low-lying escape routes flood 2-4 hours before arrival of center. Small Craft in unprotected anchorages break moorings.
Examples: Hurricane Bertha (1996), Georges (keys landfall) (1998)

3

111-130 mph

945-964 MB

 Some structural damage to small residences and utility buildings with a minor amount of curtainwall failures. Mobile homes are destroyed. Flooding near the coast destroys smaller structures with larger structures damaged by floating debris. Terrain continuously lower than 5 feet ASL may be flooded inland 8 miles or more.
Example: Hurricane Opal (1995), Hurricane Fran (1996)

4

131-155 mph

920-944 MB

 More extensive curtainwall failures with some complete roof structure failure on small residences. Major erosion of beach areas. Major damage to lower floors of structures near the shore. Terrain continuously lower than 10 feet ASL may be flooded requiring massive evacuation of residential areas inland as far as 6 miles. Example: Hurricane Andrew (1992)

5

155 + mph

<920 MB

 Complete roof failure on many residences and industrial buildings. Some complete building failures with small utility buildings blown over or away. Major damage to lower floors of all structures located less than 15 feet ASL and within 500 yards of the shoreline. Massive evacuation of residential areas on low ground within 5 to 10 miles of the shoreline may be required.
Examples: Hurricane Camille (1969), Mitch (1998)


Wind in hurricanes is the second most destructive part of a hurricane, under the storm surge. In the stronger storms it can lift the roofs off of homes and drive planks through trees. Weaker ones can wreak havoc on power lines, traffic signals, fencing, transformers, and roofing materials. The worst wind of the storm is usually in what is called the "dangerous semicircle", or the half of the storm (right or left) of the forward motion of a system. (For example, the worst half of a hurricane moving over florida would be the northern and eastern semicircle, since the forward motion adds to the general windspeed of the system, whereas the western and southern sections are slightly less. The opposite of the Dangerous Semicircle is the relatively "Navigable" Semicircle for that reason.

Most tornadoes in hurricanes are short lived and weak, but even a weak one can tear up things. Microswirls in the eyewall of very intense storms (like Andrew) aren't really tornadoes, and are just products of a very intense eyewall. Tornadoes mainly form in the outlying rain bands of systems as they make landfall.

This Sunday many local newspapers will have their 2001 Hurricane Special sections. Including the Orlando Sentinel and Florida Today. These special sections contain vitals in printed form, and are good to keep around.

I know that Orlando's WFTV Channel 9 has been running hurricane bits during the 5PM newscasts this week. They are having the Early Warning 9: Storm Ready hurricane special Thursday night at 8PM.

Other stations also usually have a half hour to hour long hurricane season special during the week before the start of the season. I was unable to find out the schedules in my pass through. If anyone knows the schedule of these for other stations, please leave a comment here so all can see. (This could be for any region, not just east Central Florida)

Thanks

- [mac]

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Displaying Talkbacks #1 - #1 (of 1 total)
THE NUMBERS (#1)
Posted by: LONNY Location: HOLLYWOOD,FL
Posted On 05:48PM 22-May-2001 with id (QURNQVSNQYUNRPQ*)

When NOAA came out with their predictions it didn't surprise me that they were almost exact numbers as Dr. Grey and his team. Each year they seem to be the same. The main factor left seems to be El Nino. Will it come or will it stay neutral. Heck it could go back to La nina. Who knows. The QBO phase that Dr. Grey was talking about on his web page doesn't make much sense to me. If the phase changes every 26 months that would mean it was in a east phase about two years ago which was a busy season. So what are the factors? I don't know...
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