It has been tough forecasting this storm over the past couple of days as the models have been all over the place. At this current time, we are going to give it a go and tell you what looks to happen as of now. Just beware that things could still change some.
As of now, a low will be moving out of Kansas early tomorrow morning, and this will give us a shot of rain, freezing rain and snow. Rain is now working its way into southern Iowa and this will spread north, northeast throughout the night. All rain is expected tonight for mainly central and southeastern Iowa before there is a small break across central Iowa tomorrow morning. This break will take place between 6 AM and 10 AM. Some areas across the state could see a good amount of rainfall out of this. As it stands right now, central Iowa could see anywhere from 1/4 to 1/2 inch of rain, with southeast Iowa seeing anywhere from 1/2 to 1 inch of rainfall. It is possible that the far southeast corner could see as much as 1.25 inches of rain. This is why a flood watch is posted for this area. The concern is if heavier rains do occur, some minor flooding on roadways could occur, along with streams and rivers due to the fact that some areas will have snow clogging their storm drains which won’t allow for the water to go anywhere. Also, the ground is still frozen so the water won’t be able to soak into the ground. The image that we have posted is where our model thinks the best chance for rain will be, and these are the areas shaded in green.
Part two of the storm of course is the snow and wind. Right now it looks like snow will move into western Iowa around 5 AM to 6 AM Thursday morning. This is a possibility that this snow could be mixed with some light rain and sleet initially, but this mix won’t last long as colder air filters in and changes any mixture to all snow. The snow will continue to push eastward and reach central Iowa between 10 AM and the noon hour. Once again the snow could start off as a mix initially for area from around Des Moines and to the south where temperatures will be just a touch warmer. Any mix would change over quickly to snow. The snow could come down heavily for a time, especially for central, northern, and northeast Iowa. This is the area where blizzard warnings and winter storm warnings are posted. Snowfall rates could be as high as 2 inches per hour, especially if you see any thunder snow.
The snow will continue to fall over central through 6 PM to 7 PM and over eastern Iowa through 8 PM to 9 PM. Most of the accumulating snows will be done by that time for the state. Total snowfall at this to be in the range of 3-5 inches for the Des Moines area, with lower amounts of a general 2-4 inches for western Iowa with those lower amounts in far northwest corner. Northern and northeast Iowa will see the highest totals from the storm. Right now areas from around Ames, Marshalltown and Fort Dodge could see anywhere from 5-7 inches, with 8-9 inches possible across far northern Iowa. This would include areas like Mason City, Charles City, and Decorah.
Then we have the issue of strong winds. Winds will be quite low in speed in the morning, but then pick of significantly in the afternoon and evening hours. This strong wind could hit at the same time some of the heavier snow bands are hitting as well. The combination of the falling snow, and snow on the ground along with strong winds will create near whiteout conditions for central, northern, and northeastern Iowa. Sustained winds of 20-35 MPH with gusts from 40-50 MPH are expected in the afternoon and nighttime hours. This is why the warnings are in effect through 6 AM Friday morning. Winds will start to die down during the day on Friday, and everyone will be able to dig out from yet another snowfall.
If temperatures are warmer, this would mean that less would fall. If temperatures cool down quicker that currently thought, then snowfall totals could be higher. One more factor to take in consideration is the storm track. If the system tracks more to the west or the east, this could affect snow totals as well. We will be watching things closely as we always do and bring you any updates we have on our Twitter and Facebook pages.