5 things to know about tornado warnings

NORMAN, Okla. (AP) — Here are five things to know about tornado warnings as the spring severe weather season approaches:

1. WARNINGS ARE ISSUED AN AVERAGE OF 15 MINUTES IN ADVANCE

Warnings are issued 15 minutes before a tornado develops, on average, said Rick Smith, warning coordination meteorologist at the National Weather Service in Norman, Okla. But because that's an average, there can be shorter warning times and longer ones. When the EF5 tornado ripped through Moore, Okla., last May, some areas had a 45-minute warning, Smith said.

1. A LOCAL NATIONAL WEATHER SERVICE OFFICE ISSUES THE WARNING

Regardless of where you see them — on a smartphone, a website or on TV — the warning originates at a local National Weather Service office.

1. WARNING AREAS ARE SMALL

A tornado watch can cover entire states, advising people that tornadoes may develop, but an actual warning area is much smaller and polygon-shaped.

1. NEVER TRY TO OUTRUN A TORNADO

People should never be in their car during a tornado warning, Smith said. If you must, stay at work 15 minutes longer so you're not out as bad weather approaches. "This business of people jumping in their car and running when they hear the sirens, it's too late for that at that point," Smith said.

1. TRUST THE WARNING

It may not always be possible to see or hear a tornado once a warning has been issued, but trust the forecasters who have issued the warning. "In Oklahoma, we're very conservative with tornado warnings," Smith said. "We don't issue a lot of them. We encourage people if you hear one, to treat it seriously."