Here is a detailed analysis of the storm this week.

Starting Wednesday, the precipitation will be starting out as a mix of freezing rain and sleet across most of the state, except in NW Iowa, where it will be in the form of snow. As the day progresses toward evening, some warmer air will move into SE Iowa and the precipitation may change to all rain, while the mix of freezing rain and sleet moves north of US Hwy 30. Snow will likely continue in NW and extreme northern Iowa.

By Thursday morning, the precipitation should be all rain or a mix of rain and freezing rain depending on local temperatures at the surface, except in NW Iowa, where it will still be in the form of snow or a mix of snow and sleet. Temperatures may just be at or slightly above freezing in the southeastern 2/3rd of the state and the precipitation may change from rain to freezing rain and sleet and back again at any time of the day.

By Christmas Eve Night, colder air will begin to win the battle, the precipitation will change back to a mix of freezing rain, sleet and snow over the eastern half of the state as the night progresses, while the western half changes to all snow. Winds will begin increasing in western Iowa from the north towards sunrise Christmas Morning.

Christmas Day morning, most of the precipitation will have switched over to all snow across the state, with the eastern part of the state starting the day with a mix but quickly changing over to all snow by mid to late morning. Winds will be light with the low over central Iowa, except in western Iowa, where increasingly strong northerly winds will take hold.

By Christmas Day Evening, the snow will be continuing across the state. Light to moderate accumulations will likely be taking place from this time through Saturday when the snow will decrease in intensity and in coverage. On Saturday, the widespread snow will be waning, with only a few snow showers and flurries across the state. Winds will be switching to the north across the state as the low pressure system finally begins to move out of the state.

These maps were based off of the 12z GFS model run this morning and there could be some variations still with the track of the low and the precipitation type that might occur. This is a best guess on what will be going on where at what time. Travel will likely be seriously impacted throughout this event and an emergency kit in your vehicle (if you’re traveling) should be a necessity. More updates to follow.