Weather worries reign supreme as U.S. Open starts
ARDMORE, Pa. -- This could get ugly.
With Merion's East Course already having taken on three inches of rain since last Friday, the forecast on Thursday will give the USGA more heart palpitations.
Play has begun on Thursday -- follow the U.S. Open Tracker here -- but thunderstorms are looking likely between 8 a.m. and 9 a.m. EDT (weather.com calling for a 30 percent chance), which would take the players off the course.
Weather.com is forecasting a minor break near noon, but followed by upwards of 60 percent chances of "strong storms" all afternoon, with hail and minor winds.
With two days of sun, the course had begun to dry out, although there are plenty of muddy spots.
The storm is being referred to as a potential derecho, which can be likened to a tornado, just on a more widespread scale.
"A tornado, when it does occur, may be on the magnitude of a mile or two wide; a derecho could go for hundreds of miles producing significant damage so winds in excess of 75 miles or greater and could run for hundreds of miles," Jim Keeney, weather program manager at the National Weather Service, told cbsnews.com.
While the thunderstorms and hail can be damaging, it is the high winds that can cause the most damage. In 2012, golf fans saw a derecho hit the AT&T National, where fans were not allowed on the grounds for the third round, leaving players to play "moving day" through debris.