El Nino may have been one factor

Oct. 27 - Forget the debates over the Broncos' new uniforms. This makes those bets about the Rolling Stones surviving the 401K tour look like chump change. It may even be better than the fat Elvis-thin Elvis arguments.

Can the worst October blizzard to hit Colorado in 74 years be attributed to that bad boy "El Nino?" Well, sorta.

"The point to be made is, there really is a probabalistic nature to these kind of events where a lot of factors have to come together to produce a system like this," Dr. Klaus Weickmann, a research meteorologist at the National Oceanic and Atmospheric Administration in Boulder, said Sunday.

In other words, El Nino was just one of several weather ingredients that coincided to cause the weekend storm that dumped up to two feet of snow on the eastern half of Colorado, stranded thousands of people and closed two airports.

Weather patterns as far off as tropical rainfall over the Pacific near the international dateline two to three weeks ago rearranged the jetstream, Weickmann said. Just before that a big high-pressure area sat off the Pacific Northwest coast.

Throw in early October rainfall, a low-pressure system replaced by a high-pressure one in the Pacific Northwest, then a cold-air mass funnel along the Rockies by a low-pressure downstream flow and voila! Blizzard strikes state.

In layman's terms, El Nino can be thought of as the flour in a recipe for bread.

"There are a lot of ingredients that have to come together, and El Nino is one of those ingredients," Weickmann said. Perhaps more than bad weather, El Nino is triggering a lot of scientific debate over its true effects on Colorado's weather. Some scientists have warned that the weathermaker that warms the Pacific Ocean could bring conditions of Biblical proportions. Others say you simply can't predict it.

The arguing has been helped by looking back at a so-called El Nino winter. In 1982-83, scientists attribute El Nino with leading to 2,000 deaths worldwide and more than $8 billion in damage with floods, snowstorms, drought and fires. In Colorado, El Nino was blamed for the Blizzard of 1982 on Christmas Eve, when 24 inches of snow blanketed Denver in a 24-hour period, and a wetter-than-usual spring of 1983.

"You can't really say that any particular storm occurred or not because of El Nino," said Chad Gimmestad of the National Weather Service in Denver. "The best we can say is there is a tendency for certain events to happen, looking at El Nino years, and being able to speculate on a physical connection between a particular storm and El Nino." But Weickmann said scientists should look at how dramatically El Nino affects storms in the Pacific.

"The El Nino has a profound impact on how storms move," he said.

OK, but let's talk about the realities of an El Nino winter. Do you replace the Sorrels? Invest in a four-wheel drive? Buy ski clothes for work?

Not so fast.

Weickmann said that although it's tough to predict any weather with El Nino, scientists are looking at the historical record and can make a couple guesses.

He thinks temperatures this winter will be on the average side, he doesn't know how much precipitation Colorado will get. But late this winter or this spring, Weickmann said we can expect cold, wet weather.

Or put in Weickmann's terms, he'll be skiing this spring, not engaging in his usual pasttime of softball.

"This spring I'm planning on maybe taking a ski vacation in the southern part of the state. I think there's a good chance of some pretty good snow pack," he said.

"I don't think I want to play softball this coming spring because I think it's going to be lousy weather. And who wants to be out playing softball when it's lousy and cold?"