Meteorological winter begins Friday Dec. 1. The weather maps are finally getting the hint.

The latest forecast models scream "major upper air pattern change" next week. The looming jet stream buckle looks ready to shove the season's coldest air mass so far into Minnesota by late next week.

Buckle up Minnesota. Here it comes.

Mild for now

For now much of Minnesota basks in highs in the 40s. Temperatures run 10 to 15 degrees warmer than average for the next few days. Enjoy this, mild weather fans. This may be the warmest week in the Twin Cities until at least March.

NOAA forecast temps via Weather Bell.

Siberian express developing

The coldest air on planet Earth is pooled over Siberia now. It's 65 degrees below zero in eastern Siberia this week.

Cross-polar flow developing?

There are signs that the upper is pattern is about to buckle and drive that bitter Siberian air mass into North America. Wind blowing across the polar regions (cross-polar flow) may push the Siberian air mass into Minnesota and the eastern United States next week.

Climate Reanalyzer.

Full-latitude trough

In meteorology, we call these huge dips in the jet stream a full-latitude troughs. Take a look at the upper air forecast map for 6 p.m. Minnesota time Dec. 13. That's a potential polar vortex chunk spinning over Minnesota.

NOAA

-20 close to home?

The American and Canadian models push the mother lode of cold toward the Upper Midwest starting late next week. The Canadian GEM model paints temperatures colder than -20 into North Dakota the morning of Friday Dec. 8. That should get our attention. And freeze up some lakes.

Canadian GEM model forecasttemps for midnight December 8 via tropical tidbits.

Twin Cities: Approaching zero?

Snow cover is a big factor in just how cold we get in Minnesota in winter. A good fresh snow blanket can easily knock at least 10 degrees off overnight low temperatures on clear, calm nights.

It's hard to get subzero temps in the Twin Cities without a decent snow cover. No snow, no below? That rule of thumb has served me well in 30 years of forecasting Twin Cities weather.

The National Oceanic and Atmospheric Administration's Global Forecast System cranks out numbers approaching zero in the Twin Cities by Dec. 9.

NOAA via Meteostar.

Stay tuned.