The Enhanced Fujita Scale is used to assign tornadoes a rating based on estimated wind speeds and damage.
The EF Scale became operational on Feb. 1, 2007. It was revised from the original Fujita Scale, developed in 1971 by Tetsuya Fujita, to better reflect wind speed with damage observed in tornado surveys.
Deadly Severe Weather Facts & Safety Tips:
Pollution levels hit all-time highs Thursday in Singapore as Indonesian fires burned out of control.
Severe thunderstorms with the risk of a few tornadoes will advance eastward across the northern Plains and Upper Midwest into Friday.
Evacuations and road closures have been enforced as wildfires continue to burn across the United States.
Join us on Thursday for AccuWeather LIVE as we will discuss the debate of climate change and hurricane frequency and the top five things you need to know about summer weather.
A hot and humid weekend is shaping up for Chicagoland just in time for the official start of summer, while severe thunderstorms fire nearby to the north.
Torrential rain began falling across Veracruz Thursday morning as Tropical Storm Barry near the coastline.
Circle, MT (1921)
Greatest 24-hour precipitation for the state: 11.50".
Annette, AK (1991)
Record high of 86 degrees; the old record was 79 set in 1958.
Tropical storm Arlene came on shore south of Corpus Christi. Rainfall amounts: Houston 4-5" Corpus Christi 9.10" Brownsville 3.20"