F- Wind
Scale Intensity Strength Frequency Damage Description
F1 Moderate 73-112 mph 40% Trees uprooted; cars overturned or
tornado (117-180 kph; pushed off roads; mobile homes shoved
63-97 knots) off foundations; roof surfaces torn off houses
F2 Significant 113-157 mph 24% Mobile homes destroyed; sheds and other
tornado (181-253 kph; small buildings destroyed; roofs on houses
98-136 knots) completely torn off; large trees broken and
uprooted; train boxcars tilt over; some light
objects become projectile missiles
F3 Severe 158-206 mph 6% Walls and roofs on houses blown down;
tornado (254-332 kph; metal buildings severely damaged or
137-179 knots) collapsed; forests and farmland destroyed;
large cars lifted into the air and thrown;
trains overturned
F4 Devastating 207-260 mph 2% Well-built homes nearly completely destroyed;
tornado (333-419 kph; cars thrown long distances; some structures
180-226 knots) with weaker foundations lifted and thrown;
large pieces of concrete and steel become
deadly projectiles
F5 Incredible 261-318 mph <1% Homes destroyed, with even those with good
tornado (420-512 kph; foundations lifted and thrown long distances;
227-276 knots) large office and other buildings have
considerable damage; trees debarked; cars
and other car-sized objects become
312 projectiles
When was mathematics first used to predict the weather?
O
ne of the first people to use mathematics to predict the weather was English
meteorologist Lewis Fry Richardson (1881–1953). In 1922 he proposed the
use of differential equations to forecast the weather, an idea published in his
book Weather Prediction by Numerical Process. He believed that observations
from weather stations would provide data for the initial conditions; from that
information, predictions of the weather could be made for several days ahead.But Richardson’s methods were extremely tedious and time consuming, main-
ly because they had to be done by hand in the pre-computer age. Thus, most of his
calculations came too late to be of any predictive value. Richardson determined that
60,000 people would have to do the calculations in order to predict the next day’s
weather. But his ideas did lay the foundation for modern weather forecasting.