Taking a look at the radar at 4:00 a.m. this morning or show shows a band of snow extending from Brookings, South Dakota to north of Amarillo, Texas. This is slowly beginning to move off to the east and should enter western Iowa after daybreak. A low pressure center sits over northern Wisconsin and southwest South Dakota. A cold front is clearly evident by temperatures, sitting from Osage to Fort Dodge to Audubon to Sidney. Temperatures behyind this front are in the mid-20s while temperatures are in the 50s in southeast and east central Iowa. Freezing rain is being seen across much of the state early, especially around the Mason City area where I-35 is completely covered in Cerro Gordo and Worth counties, and the Omaha metro, where a crash has already been reported on I-80 westbound east of Omaha.
This ice and freezing rain will exasperate an already dangerous travel situation. As the front passes, a “flash freeze” will be seen with any precipitation quickly freezing, with a period of freezing rain. This underneath accumulating snow will lead to very dangerous travel conditions early. Please do not travel unless you absolutely have to, and if you do, slow down, take a winter survival kit with you, and tell somebody where you will be going. Once the front moves farther southeast, we should be seeing more of a transition to all-snow after daybreak, with the heaviest snow falling through the early afternoon hours.
The latest forecast this morning has shifted things further and dropped totals just a bit. A very narrow corridor of four-to-six inches is expected from Osage and Cresco southwestward towards Boone and to Shenandoah. Totals will drop off quickly outside of this, with two-to-four inches expected for the Des Moines metro. An inch or two can be expected elsewhere. Winds will be sustained at 25-30 MPH, with gusts to 40 MPH from the north-to-northwest. Winds have already gusted to 45 MPH at Sioux City this morning.
Regardless of how much snow you receive, near-blizzard conditions are possible with significant travel impacts. Winter Storm Warnings remain in effect for north central, central, and west central Iowa through 6:00 p.m. this evening. Areas northwest of this have all been downgraded to a Winter Weather Advisory until this evening. Eastern Iowa is now also under a Winter Weather Advisory for light sleet and snow through midnight.
Stay tuned to the Iowa Weather Network for the latest information on this system.