It's March, so be prepared for any kind of weather

By Bryan Painter

Published: March 2, 2008

Guess which season can lay claim to five of Oklahoma's top 10 snowstorms, based on reported snowfall totals, since 1951?

Answer: Spring.

Now, before you think that I'm predicting cold weather ahead, remember, this is Oklahoma.

I have often joked that Oklahoma has all four seasons in one week, and I think spring is the best example. So if you want to know what is possible in terms of spring weather in Oklahoma this year, the best answer would be: just about anything.

Gary McManus, assistant state climatologist for the Oklahoma Climatological Survey, took a historical look at this incredible season. Now first remember that, as a climatologist, his spring season is March 1 to May 31.

Five of the top 10 Oklahoma snowstorms since 1951 occurred in March.

McManus found information from a study by Mike Branick at the National Weather Service in Norman that included the following: "An interesting note is that major snowstorms, producing maximum storm totals of 16 inches or more, show a marked preference for March.”

After looking at this information McManus came to a conclusion.

"This is no doubt a by-product of the fact that warmer air can hold more moisture,” McManus said. "So heavy snows are definitely possible into spring.”

But not all moisture comes as snow.

"The most startling contrast in spring weather that comes to mind is the famine-feast of the 1956-57 springs,” he said.

Oklahoma's drought from 1950 to 1956 was horrible. In fact, the statewide average rainfall of 6.73 inches in 1956 ranks as the 11th-driest spring in Oklahoma. However, a statewide average 22.74 inches of precipitation fell in spring 1957, making it the wettest spring in state history by more than 4 inches.

In 2005 we had the third-driest spring, and in 2006 we had the 46th-driest spring in records dating back to 1895, according to the Oklahoma Climatological Survey. So we had two top 50s in two years. But think back to last spring, the 15th-wettest on record.

Since we're on the subject of last spring, let's talk about temperatures.

"Not only was April cooler than normal, it was cooler than March,” he said, "which marks only the second time since 1895 that March was warmer than April statewide.”

But wait, there's more. While April 2007 was the eighth-coolest on record, April 2006 was the warmest on record.

Hot, cold, dry, wet. Get the picture?

Let's go back to rainfall.

"Spring chaos can set up for long-term patterns which bring feast or famine to the state, and sometimes those calamities go hand-in-hand,” he said. "Rainfalls by the lake-full, due to the convective nature of our precipitation, often setting the stage for tragedy.”

McManus referred to the Tulsa flood in which more than 12 inches of rain fell overnight between May 26-27, 1984. Subsequent flooding left 14 dead and destroyed or damaged 5,500 homes and more than 7,000 vehicles, he said.

Fifty years earlier, heavy rains led to the Hammon flood on the Washita River. During that storm, 14 inches of rain fell in six hours, leading to floodwaters that claimed 17 lives.

In those cases rain — too much — proved to be tragic. But a lack of rain can also lead to tragedies.

The storm systems that create Oklahoma's violent spring weather rely on one thing: the presence of moisture, McManus said.

"Should a strong storm system move across the state without the benefit of bounty from the Gulf of Mexico, the result is often unpleasant,” he said. "Winds that can gust to over 60 miles per hour behind the dryline, without a drop of rain preceding it, help fuel wildfires and give the state a lovely coating of dust.”

So now that we've traveled back, let's take a look ahead with Mike Foster, meteorologist in charge at the National Weather Service's forecast office in Norman. Foster said that for periods beyond about two weeks, predictions move from the realm of weather forecasts to climate outlooks.

"For the coming spring the climate outlook appears to be dominated by the large scale La Nina pattern that has been in place since last fall,” he said. "The climate outlook for western and central Oklahoma for March through May is for warmer than normal temperatures and less than normal precipitation.”

He said while there may be a trend toward normal precipitation toward the end of the spring months, the drought that developed in southwestern and extreme western Oklahoma over the last few months is expected to persist. But we're talking spring in Oklahoma, so about anything is possible.

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