ST. LOUIS — The early-week storm was definitely going to be interesting, and it has not disappointed thus far! I also want to be clear to remind folks that just because I refer to it as a potent or major winter storm, that does not necessarily mean big snows for everyone. And in fact, there will be far more people in my 36-county viewing area who do not see big snow from this storm than do. But that doesn’t mean it is not a potent winter storm; it just means we don’t get the worst of it.
So, what am I thinking? It’s complicated, but I’ll do my best to sort out what I see happening.
Rain will move into central and eastern Missouri late in the day Monday. That rain will encounter some very dry air about 5,000 feet off the ground which will help transition the rain to wet snow. That transition should take place as far south as I-44 in Missouri and about I-70 in Illinois. Southeast of there, it looks like a cold rain Monday night. This leaves metropolitan St. Louis in the middle (as usual). I think the metro will see at least a short period of transition to wet snow Monday night, with several hours of snow possible. Ultimately, warm air flowing in from the south will win the battle and the snow will kick back to rain from the south to the north late at night. By sunrise Tuesday, the rain/snow line will have retreated north of I-70 to near a line from Bowling Green over to near Girard (just south of Springfield) in Illinois. That means when folks wake up Tuesday morning, there may be some snow on the ground but it will be raining.
The storm center passes near St. Louis during the morning with clouds and drizzle, but temperatures will be above freezing so there are no ice concerns.
The wrap-around from the storm will sweep colder air across the region late Tuesday morning and through the afternoon. The colder air will come with very gusty and cold northwest winds, which could reach 35+ mph at times. In addition, moisture wrapping around the backside will swing back across much of the area and this time it will be snow. The most likely area for additional accumulating snow Tuesday afternoon will be north of a line from Hermann, Missouri to Jeryseyville, Illinois. A couple more inches may fall in those areas. Further south, some wind-blown snow is likely, but significant additional accumulation does not appear likely. For St. Louis some wind blown light snow or flurries will be around for the Tuesday evening drive, but that’s the extent of it .
So there you have it, a complicated and very interesting storm for our region. But for many of you, it will not be a major snow producer, unless you are reading this from somewhere north of I-70 and west of St. Louis.