Increasingly interesting

Tonight - downright cold. You wouldn't have to travel overly far to find places that are already in the single digits. Tomorrow afternoon, a weak Alberta Clipper will approach, bringing snow showers late in the day. Light snow will continue through the overnight, but I'm only expecting 1-2" out of that system.

Moving ahead to Tuesday, however... it's still looking very interesting. The computer models are now starting to have more similarities - enough that I can feel more confident in stating that a winter storm is likely in the Midwest on Tuesday (perhaps lasting into Tuesday night). The precise location of who will receive what type of precipitation is still hazy, though. Presently, it appears that we may have a period of snow transition over to a mix Monday night or the first part of the day on Tuesday. That would be followed by a rapid surge of cold air that would switch precipitation back over to all-snow with substantial blowing snow.

The two major computer models - the NAM and the GFS - are still disagreeing on details, though, which is to be expected. The GFS brings the brunt of the activity in late Tuesday/Tuesday night, while the NAM moves the system through more quickly. I'm siding with the GFS since these large systems tend to move more slowly. If the GFS is correct, Tuesday evening/night would have very poor weather conditions (purple circled area indicates heavy snow). The potential exists for a significant amount of snow (liquid totals near 1" translates to... well, a lot of snow). However, a longer period of a mix or all-rain would greatly lower snowfall amounts. In addition, the wind on the backside of the stormsystem would create an additional hazard of blowing snow.

The time period from Monday night through Wednesday morning bears close watching. We'll continue to analyze this scenario over the next few days.

A final note... I'm not going to discuss exact snowfall totals yet because a lot can still change. I will speculate, however, that Winter Storm Watches will be issued by this time tomorrow.