Mild temperatures through midweek. Rain/snow mix. Cold for Christmas.
All is quiet on the local weather front today, with mostly sunny skies in place ahead of a frontal boundary to our north. The southwesterly flow ahead of that boundary has allowed temperatures to warm into the upper 50s this afternoon. That frontal boundary will stall to our north, keeping the colder air over the Midwest and Ohio Valley for a few more days.
Tonight will be seasonably chilly, with overnight lows in the low to mid 30s. Most folks will be near or a few degrees above the freezing mark by daybreak on Tuesday. From there, we expect the seasonably mild weather continue for a couple more days before the weather pattern across the U.S. goes through big big changes and brings much colder air to our local area.
The big changes start by Wednesday afternoon and evening as showers overspread the area ahead of the big cold front. Rain gets more steady as we head into the overnight and may become heavy at times and even be mixed with a few rumbles of thunder as the cold front itself passes through. No severe weather is expected, however. Then, toward the predawn hours of Thursday (Christmas Eve), much colder air rushes in rapidly behind the front. If the cold air moves in fast enough before the moisture completely clears out. some of the rain may be able to change over to light sleet and snow for a few hours early on Thursday morning. The latest Futurecast model data clears that out of our area by mid to late morning, with skies becoming clear and temperatures dropping through the day. As is often the case with cold frontal passages, we really are not looking at any significant snow accumulations. For that to happen, you almost always need either a low pressure in the Gulf or an upper-level low passing overhead, and we have neither in this case. This is just a scenario with cold air chasing behind moisture that is moving out. Still, it will be neat to see snow flurries on Christmas Eve morning.
The bigger story this week will be the major blast of colder air that moves in during Christmas Eve and sets up shop for Christmas Day across the Tennessee Valley. Overnight lows on Christmas Eve look to be as cold as the mid and upper teens. Santa is really going to appreciate that fur suit he wears for his yearly trip! Afternoon highs on Christmas Day across our area look to get no "warmer" than the mid 30s, and some of the latest data suggests we may struggle to get above freezing. We may have to bump those afternoon highs back downward for Christmas as we continue to look at the latest forecast data. We do start to moderate as we head into the weekend, with afternoon highs on Sunday back into the upper 40s.