Weather model from Monday, December 18, 2017 showing very cold air and some potential snowfall for Christmas Eve night (Sunday night)
Two very small chances…
There probably will be two weather events of note between now and Christmas Day Monday. Both are minor.
The first will occur in the Thursday-night-through-Friday-evening time frame. This event will include periodic opportunities for sprinkles or light rain showers Thursday night and Friday. Temperatures ought to be in the 40-to-45-degree range during that period. Temperatures late Friday night look to crash back into the low to mid 20s, so it’ll be a squeeze-play to see if cold air arrives quick enough for any minor remaining moisture to fall as snow Friday evening. It would really be a long shot to get any snow to accumulate to a dusting or better. Then, Saturday should be partly sunny with a high in the lower 30s. Minor snow on the lawn could be handled pretty easily by the sun at those temperatures.
Christmas Eve (night specifically) is our best chance for a white Christmas — or at least some snowfall. By Christmas Eve Night, a clipper-type system is shown diving over Eastern Iowa in the featured computer model image above. That light-green-shading represents just a tiny amount of moisture available in the atmosphere — but temperatures will be very cold — falling into the 20s and even teens from Christmas Eve Day through Christmas Day. Those temperatures would be able to make the most out of fluffing up even a few hundredths of an inch worth of moisture into some snow we could actually see on the ground.
The Gulf of Mexico, as is commonly the case for these fast-moving clipper storms, will be closed for business. Also, as has been the trend over the previous week, this clipper could end up missing us entirely to the north. The timing could be off by a day or so. The clipper could end up being stronger or weaker than what currently appears to be the case. There are many variables here — with little room for error now if we’re to have some snow for Christmas this year.
For holiday travel plans or otherwise, as of right now, I would plan for cold, overcast weather for Christmas Eve Day Sunday with periods of very light snow becoming more likely by later in the day/evening and particularly into Christmas Eve night. Christmas Day Monday will likely be cold and dry — maybe a few flurries.