Overcast skies have again invaded the Tennessee Valley this afternoon as an upper-level disturbance has moved through. This system has brought showers to our area and a wintry mix to areas JUST north of our viewing counties. The back side of that is already moving from west to east through middle Tennessee as of this mid afternoon, and that will be out of the way completely overnight tonight.
Northwest winds behind the system overnight will bring cooler air into the region. Cloud cover will be slow to clear though, and with the gusty northwest winds instead of calm conditions, that will keep us from getting too terribly cold overnight. However, we expect morning lows by daybreak on Thursday in the mid 20s for most everyone, and those gusty northwest winds will actually drop wind chill values down into the mid teens in southern Tennessee and the upper teens to near 20 in north Mississippi and north Alabama! Definitely bundle up if you have to head out in the morning!
We have good news and bad news. We'll go ahead and get the bad news out of the way first. After a chilly start to Thursday, it doesn't really warm up a lot either. Despite decreasing clouds and sunny conditions by afternoon, daytime highs will only reach the lower 40s, and it's quite conceivable that some folks may not get out of the upper 30s. That naturally means that we go back into the ice cream freezer for Thursday night as well, with overnight lows a couple degrees colder than tonight! The good news is that this is a quick-hitting cold shot, and we are already back to moderating temperatures and highs close to 50 on Friday, and back into the low to even middle 50s by the weekend before another cold front brings slightly cooler air to start next week.
That milder air will be accompanied by increasing moisture as southerly winds crank up across the area as high pressure shifts off to the east and that next cold front approaches. Showers may start in the area as early as daybreak on Saturday, but they become more widespread through the day, lasting into Saturday night. The cold front moves through early on Sunday, bringing an end to the shower chances and then gradually clearing skies for Sunday into Monday.