National Data - NOAA's

referred to as "yellow box" by meteorologists and storm chasers) is issued when weather conditions ... The sky does sometimes turn green when severe thunderstorms are present, but there may or may not be a tornado forming. The green color is not completely ... Severe Thunderstorms Across Southeastern Australia Image. Caption explains image. Click here to view high-resolution version (130.39KB) ... (Severe thunderstorms are defined in the United States as having either tornadoes, gusts at least 58 mph, or hail at least 34 inch in diameter. ... Severe thunderstorms moving into region this morning - Utica, NY - The The NWS declares that a thunderstorm is severe if wind gusts reach 57.5 mph ... Downdrafts in severe thunderstorms can

create gusty winds with speeds that ... Global warming could lead to weather conditions that spawn severe thunderstorms in the United States, according to research appearing in the early edition ... As of 4:55 pm, severe thunderstorms have hit hard across the west and northwest suburbs. At west suburban Sugar Grove, winds were clocked at 60 mph along ... Thunderstorms, ranging from mild to severe, are the most common weather formation, ... Severe thunderstorms are defined by one or more of the following ... Of the estimated 100000 thunderstorms that occur each year in the United States, only about 10% are classified as severe. Severe

thunderstorms can produce ... The focus of the training series is the development of a thunderstorm and a discussion of the physical characteristics and severe weather ... hailstorms Australia Observation Weather Education online book sunsets sunrises clouds thunderstorms tornadoes bush fires wild fires precipitation rain snow ... Severe Weather Center provides thunderstorm probability

... Severe thunderstorms occur worldwide, but are most severe in the Plains of the ... About 10 percent of thunderstorms are classified as severeone that produces hail at least three-quarters

of an inch in diameter, has winds of 58 miles per ... Severe Thunderstorm Watch -conditions are conducive to the development