Tranquil weather has finally entered back into the region tonight with a block of high pressure over the High Plains keeping things under control. The cold front which brought a huge temperature difference to the area a few days back now sits from northern Michigan through Texas. However, attention now turns to the next system which will impact our area.
The aforementioned high pressure center will move off further to the northeast Wednesday with winds shifting east to southeasterly. In the upper-levels, a small shortwave will flow northeasterly from the exiting longwave trough in the southwestern United States. With some moisture and lifting over the area, precipitation will develop over the region Wednesday evening. The precise timing of this setup is still a bit up in the air and the fine details will need to be worked out in the next few days.
Our current thought is that light snow will develop Wednesday evening and into early Thursday morning, beginning over southwest Iowa. However, beyond this point, snow will begin to transition to a snow/freezing rain mix over southwestern Iowa, impacting the morning commute on Thursday, before transitioning to all freezing rain by mid-morning. This transition should occur over the rest of the state by afternoon. In far northwest Iowa, the precipitation-type will remain mostly snow, with two-to-four inches of snowfall expected northwest of a line from Decorah to Council Bluffs, where the snowfall will hang around the longest. Further southeast, higher freezing rain totals are expected with one-to-two tenths of an inch expected. The heaviest period of freezing rain will occur during the afternoon and evening commutes on Thursday.
Much of this activity should be out of the area by the early morning hours on Friday. However, some impacts are possible in eastern Iowa during the Friday morning commute – our main areas of concern would be Interstate 80 from Iowa City to Davenport and perhaps Interstate 380 as well. Nonetheless, keep an eye on the forecast, and make appropriate precautions.
Another system looks to impact the area late this weekend, in the form of a snow/rain event. Models have hinted at potential significant accumulations; we should get additional details as we go through this week, but far northwest Iowa, as usual, looks to be in the cards for some snow around that time frame. The GFS is pinning further active weather through the end of the model run, continuing our recent period of seemingly endless winter activity.
Stay tuned to the Iowa Weather Network for the latest information!