Season’s biggest snowfall so far likely Thursday

The biggest snowfall event so far this season is likely for much of Minnesota Thursday. Winter storm warnings are posted for much of Minnesota.

A well-organized clipper is spinning southeast into Minnesota. The system will produce snow before midnight in the Red River Valley. Snow will quickly race down Interstate 94 through St. Cloud and into the greater Twin Cities area between about 1 a.m. and 3 a.m. Thursday.

The heaviest snowfall will occur Thursday morning. There will already be snow on the ground for Thursday’s morning commute. Snowfall rates of one-half inch to 1 inch per hour are likely for several hours Thursday morning.

The National Oceanic and Atmospheric Administration’s NAM 3 km model still seems to have a good handle on the system. The forecast model loop below runs between midnight and 6 a.m. Thursday.

Forecast models continue to lay out a wide zone of 3 to 7 inches of snow across most of central Minnesota, including the Twin Cities. It still looks like there will be a sharp cutoff with lower snowfall totals south of the Twin Cities.

That trend is evident on NOAA’s latest 18Z NAM 3 km snowfall output:

NOAA’s High-Resolution Rapid Refresh model is going all in on even heavier snowfall totals of up to 8 to 9 inches in the storm’s sweet spot:

The best chance of seeing higher-end totals of around 9 inches appears to be north of the Twin Cities.

Temperatures Thursday will stay below freezing in the snow zone, so roads will be challenging.

Chilly weather in the teens will hold Friday and Saturday with subzero lows up north.

It looks like there will be enough snow for a white Christmas (at least 1 inch of snow on the ground).

Christmas week brings an extended thaw with highs in the 40s possible after Christmas Day.

Stay safe out there, Minnesota.