Central IL 5 Day Forecast (3/7/18-3/11/18)

HRRR Simulated Precip Type Showing Scattered Rain & Snow Showers Across Much of Central IL this Afternoon

        Scattered rain and snow showers will continue today across much of Central IL. A rain/snow mix will likely transition to wet snow for northern portions of Central IL later this afternoon. At the time that precip begins its transition from a mix to all snow it will also be winding down intensity. Due to the scattered nature of the rain/snow mixture as well as light intensity and relatively warm ground, I am not expecting any accumulation at this time. Similar lows to last night are expected tonight with northern portions of central IL making it into the upper 20s with low 30s across southern portions of the forecast area.

GFS Forecast Temperature Trends over the Next 5 Days

        With an upper level trough dominating the area through the 5 day period, expect below normal temps with periodic chances at a rain/snow mix associated with weak systems embedded within the northwest flow. The coldest nights of the week will be Wednesday and Thursday when overnight temps will likely bottom out in the low 20s across the north to mid 20s across the south. Expect daytime temps on Wednesday and Thursday to be several degrees below normal with highs only reaching the lower 30s across the north with mid to upper 30s across the south. A slight warming trend will get underway by the end of the week and into the weekend, with temps warming to seasonable normals.

ECMWF 500 mb Anamoly Showing Blocking East of Hudson Bay Which Will Keep an Upper Level Trough Centered Over the Eastern Half of the US through the 5 Day Period

        At this time, the best opportunities for precip over the next 5 days will occur on Friday and Sunday. Both systems will likely be relatively weak with only low precip chances across the area. A weak disturbance may potentially impact the southern half of central IL on Friday in association with a weak shortwave embedded within the NW flow. With a baroclinic zone draped across the area, there may be enough forcing for some light rain and snow showers across the southwestern half of Central IL. Greater uncertainty exists with the potential system on Sunday but there is a chance of a weak surface low pressure system dropping southeast in Central IL during the day Sunday. If this system does indeed develop it will bring at least a chance of rain or snow across much of Central IL with the best chances of seeing all snow across the northeast portions of the area. More to come on those potential systems, but at this time it does not appear that they will be any more than a nuisance.