From GRR this morning
-- Widespread freeze possible record lows Saturday--
As we have been writing about for over a week now, the upper level flow brings us air that is currently over the Arctic Circle. The 500 mb heights fall to near 535 m, which suggest (long story) but highs should not get much over 40. All of the ensemble and long range models continue to forecast lows Saturday morning from around 20 north to the mid 20s near and east of US-131. This would be a killing freeze if it happens. Sunday morning may be nearly as cold too.
-- Next system Sun/Monday ????--
As I suggested yesterday, the upper low that brings us the cold air rotates around brings another shortwave from the northern stream into our area Sunday or Monday (depending on which model you choose or which version of which model you choose). The 00z run of the ECMWF is now bringing the system farther north, like the GFS did yesterday and continues to do today. That would bring rain and snow into the area Sunday or Monday. Given this is a northern stream system, it would not have Gulf moisture so precipitation amounts would be less than a 1/4 inch. Still, if it were to snow Sunday night we could see 2 to 4 inches on grass areas by Monday morning.
Handy.