As we wrap up our current blizzard across the northern part of the state, we look ahead to the next storm set to impact the area Monday night. A large area of arctic high pressure is expected to build into the region today and bring with it sharply colder temperatures and increased precipitation chances. High temperatures for the day today were, for the most part, set at midnight with a rapid fall after that. Temperatures for the majority of the day today are expected to be near zero north and teens in the south. Strong winds, continuing to cause blowing snow issues, will also cause wind chills to the -20 to -30 range at times. Lows tonight should be below zero for nearly the entire state with negative teens in the north and negative single digits in the south.

Models are still somewhat inconsistent with the entire plan of how things are supposed to go Monday night. A shortwave is flying it’s way toward the region from near Alaska. Along this wave is expected to be a very large/broad area of snow, approximately 200-300 miles wide, with a more intense band, around 50-100 miles wide with heavier snow. This is a wild card in the forecast on where the heaviest snow may be. Models are still kinking out the placement of the shortwave and where snow is going to fall. The GFS, the American model, continues to push things farther south (near DSM) while the NAM has been keeping things farther north into the north central part of the state. While other models have somewhat of a consensus with the GFS, models again have been shaky with the placement of things, and a blend between the NAM and the GFS is currently what we are going with until we get a better handle on all of this.

We are suspecting that snow will begin falling in the western part of Iowa around 1-3 PM on Monday before trekking into central Iowa later into the evening and eventually into eastern Iowa. Winter Storm Watches have been posted for the northeastern half of the state from Monday afternoon through Tuesday evening. The highest accumulations are expected in north Central Iowa with 7-9″ possible around Mason City. 5-7″ is possible around this from Rock Rapids to Fort Dodge to Dubuque and up through La Crosse and Decorah. 3-5″ is possible for the Des Moines and Quad Cities metros. 1-3″ will be possible in Sioux City to Ottumwa and up through Wapello. Southeastern Iowa and far extreme southwestern Iowa should remain under an inch this time around. The snow cutoff line will be interesting with 5-7″ possible in Sac City and 1-3″ possible in Onawa (~80 miles). High snowfall ratios of nearly 20:1 will cause any snow that falls to be rather light and fluffy, as compared to wet and heavy as we have seen recently.

Winds are another concern with 20-30 MPH wind gusts possible Tuesday morning. This will easily blow the light and powdery snow around, reducing visibilities and making travel hazardous. School delays & cancellations are possible Tuesday morning with near-blizzard like conditions and potentially bad road conditions, if things are not cleared up by that point. This system will need to be watched as we get into today and tomorrow as it is the most high-impact event we have seen so far this year. Keep it tuned to the Iowa Weather Network for the latest on this situation.