Rain, possibly even freezing rain this weekend? GFS thinks so. ECMWF does not.

Note that a significant severe weather event is possible today in parts of Texas and Oklahoma, with a fairly widespread tornado risk. More on that below.

Michigan may see its first true bout of wintry precipitation this coming weekend. I say May because not all models are in agreement on this one; namely, the ECMWF model doesn't predict anything at all. However, several GFS runs have predicted a storm system developing Saturday morning and staying with us throughout the day. According to this forecast, as the day goes on, the temperatures would drop, meaning what would start out as rain could change over into freezing rain, sleet, and possibly even snow in some areas. See the loops below for details.

Temperatures would be right on the cusp of freezing Saturday afternoon should this forecast verify, which would likely be enough to generate some sleet/freezing rain in some areas, if not pure snow. 

Now, onto the plains severe weather threat. This has no bearing on Michigan weather, but as always, if you have friends or family in these regions, or if you plan to travel to these areas yourself, be on guard. A very potent storm system which should bring us some rain over the coming days is on tap to affect the southern Great Plains this afternoon in what could be a fairly widespread tornado/severe wind event. I won't quite call it a potential outbreak yet, as it hasn't quite reached that threshold, but it could easily be on par/exceed what occurred in Michigan this past June 22nd, for those who remember.

An "enhanced risk" has been posted for this potential event. There's still a chance of it increasing to "moderate".

Storms should rapidly grow this afternoon over the southern portions of the plains. Initially discrete supercells will pose a tornado threat. After a few hours, they should condense into a squall line which will pose a major damaging wind threat.

My biggest concern is the forecasted 2-5km hourly maximum updraft helicity values by the NAM4KM. This is a prediction of how much 'spin' a thunderstorm updraft will have to it. The higher the value, the more rotation you have in a thunderstorm. Once you start seeing darker greens/oranges, tornadoes are almost a given.

Based on the model data and the 12z upper air observations (6AM CST) in and around the enhanced risk area, I'd say this is on track to be a very active day in the shaded regions. Again, if you know anyone in these areas, give them a heads up as to what to expect today. This region of the country is used to getting hit by these types of events, but one can't be too cautious.