How do you or tell how bad a tornados going to be? is it by force or what.?

Question

hey yall i need help how do you figure out how stroung a tornado is

Answer 1

There are currently no predictive models for tornado force.

However, tornado force is determined through forensic examination of the effect produced by the tornado's damaging winds. Although such correlation involves a number of assumptions, it is generally regarded as relatively accurate.

A tornado's force is then ranked on the Fujita or "F" scale. For your convenience, I've provided it below. Please note that, unlike hurricanes, tornados are described as "category F4" instead of simply a "category 4." Also note that tornado wind speeds and damage do not correlate to the Saffir-Simpson or other hurricane intensity scale.

F0 (aka "Gale Tornado")
Statistical Incidence: 29%
Vortex Wind Speed: 40-72 mph
Damage: Minimal
Damage Characteristics: Some damage to chimneys, TV antennas, roof shingles and windows. Breaks branches off trees, pushes over shallow-rooted trees, damages sign boards.

F1 (aka "Moderate Tornado")
Statistical Incidence: 40%
Vortex Wind Speed: 73-112 mph
Damage: Moderate
Damage Characteristics: Automobiles overturned, carports destroyed, trees uprooted, peels surface off roofs, mobile homes pushed off foundations or overturned, moving autos pushed off the roads.

F2 (aka "Significant Tornado")
Statistical Incidence: 24%
Vortex Wind Speed: 113-157 mph
Damage: Major
Damage Characteristics: Roofs torn off frame homes, sheds and outbuildings are demolished, mobile homes overturned or destroyed, boxcars pushed over; large trees snapped or uprooted, light object missiles generated.

F3 (aka "Severe Tornado")
Statistical Incidence: 6%
Vortex Wind Speed: 158-206 mph
Damage: Severe
Damage Characteristics: Exterior walls and roofs blown off well-built houses, metal buildings collapsed or are severely damaged, trains overturned, forests and farmland flattened, heavy cars lifted off the ground and thrown.

F4 (aka "Devastating Tornado")
Statistical Incidence: 2%
Vortex Wind Speed: 207-260 mph
Damage: Devastating
Damage Characteristics: Few walls, if any, standing in well-built houses, structures with weak foundations blown off some distance, large steel and concrete missiles thrown far distances, cars thrown.

F5 (aka "Incredible Tornado")
Statistical Incidence: <1%
Vortex Wind Speed: 261-318 mph
Damage: Incredible
Damage Characteristics: Homes leveled with all debris removed, strong frame houses lifted off foundations and carried considerable distances to disintegrate. Schools, motels, and other larger structures have considerable damage with exterior walls and roofs gone, steel re-inforced concrete structures badly damaged. Automobile sized missiles fly through the air in excess of 100 meters, trees debarked.

F6 (aka "Inconceivable Tornado")
Statistical Incidence: <1%
Vortex Wind Speed: 319-379 mph
Damage: Inconceivable
Damage Characteristics: These winds are very unlikely. The small area of damage they might produce would probably not be recognizable along with the mess produced by F4 and F5 wind that would surround the F6 winds. Missiles, such as cars and refrigerators would do serious secondary damage that could not be directly identified as F6 damage. If this level is ever achieved, evidence for it might only be found in some manner of ground swirl pattern, for it may never be identifiable through engineering studies.

Answer 2

Weather balloons are released into the air on average of 2 times a day for certain areas. Using this data from the sensors attached to the balloon, meteorologist can tell how unstable the atmosphere is as well as what the wind speeds and direction are. Tornadoes are formed in very unstable environments and with winds that help create rotation. Also, tornadoes tend to form when the wind speeds at the top of the storm are very Strong allowing the storm to create a downdraft and an updraft at the same time by tilting the storm (the height of these winds vary by location). The more rotation and the more unstable the environment the more severe a storm can be. There is really a lot that goes into forecasting severe weather and this is just a very small part to it. With all these "ingredients" it's very easy for a forecaster to miss something. If there is a tornado warning out expect the worse.

Answer 3

In real time (before a tornado has actually formed or is on the ground) it is very difficult to do this accurately. There are some atmospheric indices that indicate when the atmosphere is primed to produce significant tornadoes, but that doesn't mean that every tornado produced in that environment will be significant.

The SPC (http://www.spc.noaa.gov/) produces probabilistic outlooks that includes forcasted areas that would be favorable to have a significant tornado. They do this with a hatched area in conjunction with their Day 1 and Day 2 convective probabilistic outlooks.
http://www.spc.noaa.gov/products/outlook/

Here's a recent situation where the hatched areas were used. Note that if you see a hatched area on the tornado graphic, that indicates that the forecaster felt that there is a 10% chance or better that an F2-F5 tornado will occur within 25 miles of a point. This does not mean that all tornadoes within that area will meet that threshold--in fact, most will likely not.
http://www.spc.noaa.gov/products/outlook/archive/2006/day1otlk_20060824_1300.html

In addition, you cannot tell the strength of tornadoes by simply looking at its size. Some large tornadoes actually have slower winds than their smaller counterparts. (Think how an ice skater spins faster as they pull their arms in closer toward their axis of rotation)

After the tornado has produced damage, a rough estimate of the wind speeds associated with the tornado is possible by comparing the damaged caused by the tornado to the Fujita scale and the Enhanced Fujita scale.
http://www.spc.noaa.gov/efscale/

Answer 4

No one in the idiot brigade yet mentioned that the SPC and local NWS and even ordinary folks can look at Doppler radar "velocity" images and see how strong the winds are at certain locations of a storm. A problem is you only get the wind speed to & from the radar (thus velocity is not the correct term for that really), though with it spinning so quickly you'll probably see a large component in those directions in any tornado - especially for the larger ones (radar resolution can be a problem for the small ones). Most "velocity" images you can find on the web are limited at 64 knots, but perhaps the SPC & NWS can see higher speeds. A large & strong tornado typically has large 64+ knot areas. If you read tornado warnings, you'll see they often say "Doppler radar indicated a tornado signature at so-and-so location and so-and-so time".

If a tornado persists awhile, you may even get eyewitness or spotter reports as it approaches - not often will it get thru the information maze that quickly though.

One of the dummies mentioned how they can often change speed, strength, size and direction quickly - that much is true, but some information is better than none.

Answer 5

You cant - not while its approaching.
Speed and width are all that matter at that moment.
If the base of the twister is broad - more than three houses wide - its a big one. If its tall and slender - its less powerful but could still flip a car.
The big ones move slower and can usually be driven away from if you exceed 70 mph the little ones are quicker and harder to dodge.

If you can SEE the tornado find an object on the ground - a telephone pole or a car or a house and put it between you and the twister. If the tornado is moving left or right of the object, you're probably safe for now but if it appears not to move, relative to the object, that means its either going directly away from you or coming straight at you. Dont wait around to figure out which it is - find a basement or a doorway and STAY there till it goes away.

Answer 6

I am from Oklahoma tornado ally. First there is a F1 a regular tornado goes & does very little damage. But is a good gust of wind.these last usally 5 to 15 min. F2 is some times called a waterspout. or it can hit land by uprooting trees or go for the trailer parks.These last 15 to 30 min. F3 is usally called a micro burst most of the time u r not sure where it will land or end up.Usally 5 to 25 min. F4 is a half mile wide these have a tendancy to breake things in half or sling things at targets.10 to 35 min. F5 is the worst one out of all of them they r usally 1mile accross & 1mile wide these last up to 30-40 minitues. Although an F5 rarly happens that does not mean u r not in danger at all. If u encounter a tornado go for your closet with a blanket or matteress. Same for a bathtub or shower. Hopefully u have a basement, if u do then go in with essentials & stay away from the entry.

Answer 7

Forecasters and researchers following a developing hurricane can accurately measure and rate its strength soon after it begins by collecting data from storm-hunting airplanes, radars, and satellites. But experts have no similar way to judge a tornado's force before or during its touchdown, as tornadoes arise too quickly and are too dangerous to approach by airplane. Instead, after a tornado hits, the U.S. National Weather Service uses a rating system it adopted in 1973 called the Fujita Scale. Devised by meteorologist Theodore Fujita in 1970, the F-scale enables experts to estimate a tornado's maximum wind speed in relation to the single most destructive thing it did.

Answer 8

Living in Oklahoma, I've been through many tornadoes. Unfortunately, there's really no way to tell in advance how bad a tornado is gonna be. Tornadoes can change speed, size, and strength very quickly. All you really need to know is that when you hear the tornado sirens or the the weatherman tells you to take cover, do it. It's always better to be safe than sorry :0)

Answer 9

Well, one answerer had a good point. Statistically speaking...F1s and F2s are much more common than F3+. So you are probably going to encounter one of those most likely. In any case, the strength of the tornado should not determine whether you take cover or not, even an F0 can kill you.

Answer 10

There's no way to tell how bad it is going to be. You just have to wait and see. As to how bad it is when in progress, that is mainly measured by wind speed. The main trouble is that the tornado often destroys the wind-measuring instrument, and then there's no way to tell just how strong it was.

Answer 11

There is no way to tell how bad a tornado is going to be. One indication of wether or not you might have one would depend on some factors though. Air pressure for one.....