Rain to snow: White Christmas still possible

Beige Christmas?

It's going to be a nip and tuck for a white Christmas in the metro.  Santa is taking the rollerblades off and waxing the sleigh rails just in case.

Is there enough Christmas-week magic to save a white Christmas for the Twin Cities? I'm saying there's still a chance.

Weather headlines

• Winter storm warnings into early Wednesday for Red River Valley and far northwest Minnesota

• Rainy to wintry mix overnight into early Wednesday for metro (Rain, sleet, ice, snow — all possible)

• Rain changes to snow Wednesday in the Twin Cities

• Sloppy metro snow accumulations possible Wednesday

Another 'warm' December system

Wednesday brings yet another warmer-than-average weather system for late December. This one brings the now-familiar mix of rain and sleety precipitation overnight into Wednesday morning. But the latest indications are that the system may stall just long enough to let sub-freezing air feed into the system to change precipitation to all wet snow before it ends later Wednesday.

The latest read from the Twin Cities NWS is to tease out about an inch of the snow Wednesday. But a growing number of model solutions lean toward somewhat higher snowfall potential.

Two-part system

Here's a good view of the inbound system from above. Low pressure No. 1 swirls over northern Minnesota with winter storm warnings and snow piling up in the northern Red River Valley and northwest Minnesota towns. The next slug of moisture rides north overnight along the trailing front into the Twin Cities and eastern Minnesota. Here's the GOES infrared loop from College of DuPage.

There's plenty of moisture with the next wave moving north. NOAA's NAM model paints the precip over the Twin Cites and eastern Minnesota into Wisconsin. As much as .50" liquid could fall in the eastern metro.

Rain or snow?

Ah, the eternal winter storm question. In this El Nino-modified winter, predicting the infamous rain-snow line is more elusive than ever. Today's recent models trends hold out hopes for snow lovers, and for squeaking out a potentially white Christmas in the metro. The NAM is the most aggressive, kicking the 850 millibar, 0-degree isotherm (usually the most reliable rain-snow line indicator) east of the Twin Cities by midday.

The NAM is often too aggressive with snowfall in these parts. But both NOAA's GFS model and the usually trusty Euro (ECMWF) have come closer to the NAM solution, and also change rain to snow into the metro Wednesday.

At this point I'm leaning toward a slightly more aggressive snowfall Wednesday afternoon. With temperatures hovering above freezing at ground level, some may melt on contact. But I won't be shocked to see widespread 1"-plus totals, with some 2" to 3" totals somewhere close to or in the metro by Wednesday evening.

I'm not totally buying into the model notion below of 3" to 4" metro snowfall potential Wednesday night, but some sloppy 1" to 3" snowfall totals sure seem more possible than it did yesterday. Three chances for accumulating snow in the next week? If Wednesday's snow doesn't pan out, it still may get very white around the in the next week.

With sub-freezing air in the metro Christmas Eve any snow that does stick tomorrow will stay put. In other words, the NWS criteria of 1" snow depth on the ground may be met in much of the Twin Cities by the skin of our teeth.

Which begs the question. Do teeth really have skin?

Good travel Christmas Eve; still watching Christmas Day snow chances

It's getting more active out there as southwest flow aloft gets established. The next moisture wave rides northeast Christmas Day. This one look more likely to be all snow, and I can see some shovelable and potentially plowable accumulations by Saturday morning. Both the Euro and NOAA's GFS are spinning another potentially snowy low pressure storm our way next week.

It could get very white around here in the next week.

Stay tuned.