After an active week to kick off April, things have certainly quieted down. But eastern Iowa is not alone in that. The weather pattern has shifted, keeping potential storm systems away from “tornado alley.” No major outbreaks have occurred in some time, an unusual sight indeed. The graphic to the left shows every report of severe weather in Iowa so far this year. The green represents large hail and the blue marks wind reports. No tornadoes have been reported so far in 2010 (knock on wood).
How unusual is this? From my experiences in Iowa, it’s not that unusual. In recent years, early severe weather events are common in Iowa followed by a long period of quiet weather. But for the rest of the nation this is unusual. Normally, activity from Nebraska to Texas begins ramping up. Storm chasers normally focus on areas to our south, but now that’s not the case.
With few outbreaks, many career chasers made their way up to Iowa last week. Not because it was that unusual of an event, but because it was the only game in town. I’m convinced if a dry line event took shape to our South, many chasers would have avoided Iowa. Although we see our fair share of tornadoes, we do not have the reputation of states such as Oklahoma and Kansas.
Now I’m no Nostradamus. I can’t forecast long term what the weather pattern has in store for Iowa or the rest of the nation. Two years ago I wrote a blog about a phenomena called the Omega Block. The Omega Block is a weather pattern that sends storm systems away from a large area. This happened in April and May of 2008 across Iowa and much of central U.S. It looked like the year would be a bust for severe weather. But that changed very quickly.
Once that blocked moved on, storms lined up and hit Iowa and hit Iowa hard. It began with a massive EF-5 tornado and EF-3 tornado in northeast Iowa on May 25th, 2008. Numerous rounds of severe weather and heavy rain followed, leading to a historic flood across Iowa.
The bottom line for chasers and storm lovers alike, be careful what you wish for. Weather remain too natural and complex for any human or supercomputer to accurately predict on a large scale over a long period of time. Will we see epic outbreaks of severe weather this spring and summer? Maybe. Could we see a lack of any storms and deal with a summer-crushing drought? Maybe.
I know the word ‘maybe’ is convenient to use, but it’s the only prediction I am willing to give.