Originally posted by: XZeroII
Millenium, I assume you know lots about meteorology. I'm taking an intro class this semester in it, but the Fujita (sp?) scale is not applied to a tornado until after the damage is looked at since the Fujita scale measures the amount of damage done, not the wind speed or size. Basically, a tornado could be a mile wide and wind speeds of 500kts and be labeled an F0 because it never hit the ground. Our meterorlogy professor made a big point about that while discussing the movie Twister and how he thinks it was one of the worst movies ever created
This is true, however, experience has shown that large tornadoes tend to create way more damage than smaller ones. Now, what you described is not a true tornado because it didn't touch down. Only storms that touch down can be rated like you said. If there was winds of 500kts and a mile wide, it would be cause considerable damage if it touched down. You can get small compact rope tornadoes that cause F4-F5 damage but that is fairly rare. The larger the tornado, for the most part, the more damage it can create. The reason I said it looked like a F4 was because it was such as large tornado. Since damage reports have not yet said much wind damage, it could have been much smaller. I was relaying information from someone who has a lot of experience with severe weather. Until an actual NWS storm survey takes place, everything is speculation. I can tell you, however, that the last time I saw a tornado like that on the ground was in December of 2000 in Tuscaloosa County. That tornado was captured on ABC 33/40's towercam and later destroyed their storm chasing van.
Here is the video of the storm from that day. One other thing... the Fujita scale is BASED on damage done, and then give a wind estimate for the tornado. Twister was a pretty unrealistic movie, but it had some truth.
I actually would not consider myself to know a lot about meteorology. I am a storm buff, with knowledge of computer models, radar, and other things. If you really want to learn stuff about meteorology and the like go to
here and start participating in the forum. The Bham NWS has a presence on the forum, as does several meteorologist from ABC 33/40, WAFF 48, WJHG, and others.