CEDAR RAPIDS, Iowa (KCRG-TV9) - This week’s temperatures will be above normal, but generally not that far above the 84 that is our average high. There’s a reason we’re avoiding the big heat this go-around, and it has to do with the jet stream.
In a typical heat wave, the jet stream – the river of fast-moving air some 40,000 feet up – shoots north from Pacific Coast into Canada before dipping back south over the eastern United States. An expansive region of heat builds under that ridge and it’s hard for that pattern to break down. See the image at the bottom of this article to see what that looks like.
In this week’s case, the ridge is much flatter. It’s not going very far north, instead coming right across the Plains into the Midwest. This doesn’t allow lots of hot weather to develop and spread over a huge chunk of real estate. It’s enough for a smaller area to deal with heat, but that’s about it.
Our hottest day will probably be on Thursday when highs in the lower 90s and heat indices climb to about 100 degrees. Other than that, the situation through the weekend will be seasonably warm and humid, but not blistering.