I've been watching a storm system for several days now and it will impact the region tonight and Wednesday. I'm not going to lie, this has been a tough forecast and to be blunt, computer models have been pretty much clueless as to what will happen. Although there is better agreement tonight as to what will happen, even small adjustments could change things noticeably as far as snowfall totals are concerned. We'll discuss this in a moment, but either way, there will be snow that will impact travel, at least for some of us, but it won't be a crippling storm by any means.
The Low Pressure system responsible for this snow remains rather weak this evening. It will only gradually gain strength over the next 24 to 36 hours. If it strengthens quickly enough, we could see as much as 8-10 inches of snow in eastern sections of lower Michigan. I think this is unlikely, so I am not forecasting totals this high. I am forecasting the low to stay weak enough that north and west of Lansing will see 1-4" at best with a sharp cutoff in snowfall totals the further north you go. Once you get northwest of a line from Grand Rapids to Mount Pleasant snowfall totals will almost certainly be less than 1 inch and some areas may not even see a snowflake. Southeast of a line from Kalamazoo to Flint is where I expect 4-6" with higher amounts possible. There is still a small amount of wiggle room with this forecast. If anything does change, the numbers would need to be increased by 1 inch or so and the lines moved northwest by about a county. The reasoning behind this is because even though the low is weak it will eventually strengthen, but I'm not convinced it will happen quickly enough to give us 6"+, except in far southeastern areas of lower Michigan. The Low is much more likely to strengthen Wednesday night and Thursday after the snow ends, which will lead to a windy and cold day Thursday with scattered lake effect snow showers.
Snow is already moving in from the south this evening and will continue to overspread the area overnight. In the Lansing area, about 1 inch should fall by sunrise Wednesday. I don't see any major problems for the morning commute. The snow will never become too heavy, but the steady snow will continue all day Wednesday, adding about 3-4 inches during the day. Although the snow will be persistent, the light nature of the snow should prevent any major difficulty from keeping roads plowed. As a result, slippery travel conditions and areas of snow covered roads are likely, but simply allowing extra time to reach your destination should be the main inconvenience. Winds will increase late Wednesday, so areas of blowing snow and reduced visibility will be possible. Snow will end during the mid-evening hours and should be done by about 10pm.
The further northwest you are, the less snow there will be and the further southeast you are, the more snow there will be. Here is my official snowfall forecast, which is valid from this evening through tomorrow evening.
Snowfall Forecast by City:
Mt. Pleasant: <1"
Bay City: 1-3"
Grand Rapids: ~1"
The National Weather Service has issued a Winter Weather Advisory across southern Lower Michigan from this evening through Wednesday evening. This advisory is shaded in purple.