After spending most of yesterday on the road, or camped out at a Mason City McDonalds, I arrived home last night with no pictures taken, no video shot and no severe weather anywhere near where we thought it would be. All the ingredients were in place for a big severe weather day in Iowa yesterday, so what happened?
There were a lot of factors that wound up working against us. The first was the strong cap that was in place over most of Iowa during the entire afternoon and evening. The technical term for a cap is Convective Inhibition. It’s a layer of warm air above a layer of cooler air in the atmosphere. This is not the situation needed to produce thunderstorms. You need colder air aloft and the warm air at the surface.
Storm chasers all over Iowa reported seeing clouds bubble up but they never make it more than a few thousand feet. The cap preventing those storms from punching through to the higher levels of the atmosphere needed to produce severe weather.
Another reason was the timing of the storm. Models indicated the cold front would reach the center of the state by 7:00pm. It was only five hours off. with the front not reaching that point until around midnight. Even then, a strong enough cap was likely still in place to limit storm development. Some thunderstorms managed to develop, but none of them in central Iowa managed to last more than a half hour or so, and they never produced any severe weather.
There were a few storms in the early evening that produced some strong winds in western Iowa, but that was it. The bulk of the severe weather was found both to our north and south… Iowa was left out of yesterday’s event. But that doesn’t mean we won’t get out chances again. Another threat of strong storms will return on Saturday. More on that later this afternoon.