Heavy rainfall is often the last aspect of severe weather people think about, behind tornadoes, hail, wind and lightning. But here in Iowa, many know all too well the terrible impact heavy rain and the flooding it causes can have on a person’s life. Take a look at the image to the left. This is the amount of precip that has fallen across Iowa in the last 30 days.
All of the areas in Purple saw at least 10 inches of rain. The small white dot in northeast Iowa? More than 20 inches of rain over a one month period. The bulk of this rain fell last week and caused flooding in many communities and the collapse of the Lake Delhi Dam.
Once again this week we face the risk of heavy rainfall here in Iowa. The picture is still muddled, but I hope we can provide you a breakdown of the scenarios facing parts of the state. First of all there’s good news. Most of Iowa should see a prolonged period of dry weather, with the exception of Tuesday Night into Wednesday. A cold front will sweep through the state during that timeframe. But with the main thrust of energy further north, only scattered showers and thunderstorms are expected.
But after this period, things get a little more troubling. A warm front will makes its way into Iowa Thursday Night. Unfortunately the front is expected to stall somewhere in the state, allowing round after round of showers and thunderstorms to develop and cross Iowa. This is a similar pattern to what we saw last week when some areas saw more than a foot of rain in a 24 hour period, subsequently causing the disastrous flooding along the Maquoketa River in northeast Iowa.
So how long will this prolonged period of rain last? It’s hard to say, but the threat is certainly to end this week and last through the weekend, even into next week. The only good news is before all this we’ll get some time to let area rivers and streams recover from last week’s rain. Either way the soil will likely remain saturated, maintaining a threat for flash flooding and rising rivers where heavy rains set up in the coming days.
This is something that certainly needs to be watched… and we will do that, along with keep an eye on some marginal severe weather threats that might include portions of Iowa this week.