Expert: don't blame El Nino for twisters

NORMAN, Okla., March 1 (UPI) -- Don't blame El Nino if there are more tornadoes across the United States this year, the director of the National Storm Prediction Center said Friday.

Joseph T. Schaefer, one of about 300 people taking part in a national severe weather workshop, said the weather condition born of cooling in the eastern Pacific has little relationship with tornado activity one way or another.

"We were sort of disappointed," he said of a comprehensive study into a possible connection. "We thought there would be something."

Ocean temperatures taken just off the coast of Peru, where El Nino normally originates and three bands of the Pacific were studied along with the number of tornadoes, the number of violent tornadoes and the number of violent tornado days.

"The assumption was that if there was a relationship they would go up or down together," he said in an interview. "Essentially we found very few statistical significant connections. So there was very little that could be detected by sea temperature change."

One possible exception is the peninsula of Florida, he said, and that appears to be small.

There is a stronger link between the warming phenomenon and hurricanes, he said.

Tornadoes are produced on a small scale, Schaefer said, while El Nino's effects occur on a large scale.

"It has relationship to precipitation, drought, hot and cold temperatures," he said. "The atmosphere has to be in such a delicate balance to produce tornadoes. If it's an El Nino year, we're going to have precipitation in the Southeast. That's great. But just because you have rain doesn't mean you're going to have tornadoes."

This has been heralded as an El Nino year, as opposed to La Nina, which features warming of the Pacific waters.

"It looks like we¹re getting into one," he said. "They go full bore in the early fall."

All tornado and severe thunderstorm watches issued in the United States originate in the Norman-based storm prediction center, the nation¹s only all-hazard forecast center.

The center issued 852 severe thunderstorm and tornado watches in 2001, 239 of them tornado watches. The top five states for tornado reports last year were Iowa, 116; Texas, 115; Kansas, 77; Minnesota, 67, and Nebraska, 64.

Last year was considered an average year, with 1,039 twisters reported. Twenty-one of them produced 38 deaths; most of them were in February and November rather than in the normally active spring and early summer months. So far there have been only nine tornadoes this year, well below the average of 108 by March 1 in the preceding three years.

Schaefer said he did not know if the slow start would carry through the rest of 2002.

"I'd be surprised if did," he said. "We're starting to see these strong cold fronts coming through. It could be an above-average year. But most of them are in April, May and June, so it's too early to say we lucked out this year."