A brief update tonight regarding the potential snowstorm that will affect portions of Northern, and Central Illinois very late Saturday night/very early Sunday morning on into Sunday evening.
Evening model data has come in with an overall slight shift south from previous runs, but still a decent spread among guidance. While the exact location of the main axis is snow is unknown, it is fairly likely that within the main snow band there will be a corridor of 6"+ snow.
As mentioned above there is still a spread in model guidance. At this time we are favoring towards the south group of model guidance, which does have more support at this time. With that forecast, the main axis of snow would run from far N. Missouri and C. Iowa, up into much of Northern and portions of Central Illinois. Within that swath, a corridor of 6-9"+ of snow will be likely. Below is a visual representation of our current thinking on snowfall amounts, with our TAM map. Note that given the spread in model guidance, adjustments to snowfall amounts are possible. We will have further updates on this system on Saturday.