Clouds have returned again and will continue to thicken Tuesday evening. Dry conditions are expected through 9 p.m. but our weather will take another turn later in the night. Before 12 a.m. snow will have spread north form southern Indiana with sleet mixing in and freezing rain not far behind.
Warmer and moist air will overrun the colder layer at the surface and incidentally begins as a wet snow in south-central Indiana and works north through 3 a.m. Snow and sleet accumulation is likely and at times a heavy, wet snow will be falling. Accumulations will occur quickly before a change to freezing rain with amounts of as much as 3" possible. Noting trends, it looks to favor some higher totals far east and northeast, I'm posting below the latest snowfall forecast from the European computer model below and the NAM model. Both favor some locally higher snow totals east/northeast early Wednesday morning.
CRITICAL FREEZE LINE
The temperature will rise above freezing before sunrise, but the warmer and more buoyant air will temporarily overrun the cold creating a freezing rain set-up around 3 a.m. in Indianapolis. Rain falling and freezing on contact could be heavy for an hour or two following the snow. Could some locations receive a quarter-inch ice accumulation? It is possible in scattered fashion. We will monitor trends and more data will be available before the 10 p.m. broadcasts.
Over two dozen states are now under some form of winter advisory, watch and warning overnight and Wednesday.
Very icy/slick conditions are expected here before sunrise Wednesday. A Winter Weather Advisory is in effect from 10 p.m. through 10 a.m. Wednesday.
Damp and milder conditions are expected Wednesday after the early morning mix. The forecast is for temperatures to reach the upper 30s to mid 40s by Wednesday afternoon. Below are snapshots of the forecast radar along with the 32-degree surface temperature forecast (pink line). Note the 4 a.m. image that indicates moderate to heavy freezing rain over Indianapolis.
TEMPERATURE WILL RISE
Improvements will come quickly after sunrise as temperatures continue to climb. By late morning the freeze line has worked north and the far north communities will also go above freezing with the wintry weather ending and lighter rain begins falling.