It’s 5 am and I’m still up…the meteorological explorer…bouncing around the internet looking at weather data. The map above is the overnight GFS model for the morning of Jan. 26. The dotted blue lines are thickness values. In general…the lower the number, the colder the air. Grand Rapids is down to about a 493 thickness. By contrast, our current thickness is about 514 and we have a current temperature of +10°. So, the air mass that the model is forecasting is colder than the one we have now.
Keep in mind that this is a long way off and it’s likely that the timing will change and certainly possible that this map won’t be right at all. But, it’s something that I’m already keeping track of. With a second year La Nina pattern, it’s unlikely an air mass this cold would stick around for more than a few days, but this would be a real shot of Arctic air.
An air mass like this is sure to set off lake-effect snow, thought with temperatures this cold, the flakes are likely to be small and accumulations on the light to medium side. If we have a northwest wind, the lake-effect would favor the lakeshore counties and perhaps coming inland into W. Kalamazoo and Cass Counties.
Lake Michigan satellite picture from Saturday PM – Wisconsin is clear with snow on the ground. Bigger and much shallower Lake Winnebago is frozen over, while much deeper Green Lake and Geneva Lake are open water. You can see the ice in Green Bay, where those fishermen had to be rescued with the ice broke away from shore. There are lake-effect clouds forming over the lake and moving southeast over West Michigan.
ALSO: Central Indiana has not had a measured snow this meteorological winter (Since Dec 1st.) This is the first time on record without it since snow records began 137 years ago. The graph does not count snow that fell in November. Indianapolis did have 0.5″ of snow in November.