Rainy and windy conditions arrive overnight. A stray flurry Wednesday night into Thursday?
We're still holding onto quiet weather early this Tuesday morning. Regional infrared satellite "looks" cloudy, but that is actually just the infrared camera detecting the cold temperatures across the area early this morning. Temperatures are in the upper 20s in most spots, although a few locations immediately near the Tennessee River are sitting around 30-31 degrees. We do have the potential for some patchy areas of fog through the early morning hours, and with temperatures in the 20s, it would be freezing fog if it develops. That should be a rather isolated thing, but take it easy on bridges and overpasses before sunrise in case there are any isolated slick spots.
As we work through the day, a few clouds will start to roll in by midday, and we can't rule out a few showers as early as 2:00-3:00 this afternoon. Daytime highs will climb into the upper 40s and lower 50s, with maybe a few locations in the mid 50s over northern Alabama. More widespread rain moves in as we head into the evening, and it becomes heavy as we head through the overnight. This continues through the early morning hours of Wednesday morning before the widespread activity shifts east of the area by 3:00-5:00AM. We can't completely rule out a rumble of thunder, but severe storms are NOT expected. That threat will remain well south along the Gulf Coast. While we do expect a good soaking rain overnight, we are not really concerned about a flooding threat. Rain totals across the area are expected to generally range from 0.5 to 1.5 inches or so.
In addition to the widespread soaking rain overnight, a strong low-level jet a few thousand feet above the ground and the pressure gradient from the low nearby will lead to strong gusty winds overnight and into Wednesday. There is also the potential for a wake low to develop on the backside of the rain mass, and this would further increase the wind potential. A WIND ADVISORY has been issued for all of middle Tennessee and north Alabama from 9:00 PM tonight until 3:00 PM Wednesday afternoon. The most intense wind gusts appear to start in our area after 10:00pm tonight, and they may carry on right through daybreak. Sustained winds of 20-30 mph are likely, but gusts may be as high as 40-55 mph, and this may last for several hours during the overnight and early morning hours of Wednesday. Because of this, there is the potential for tree limbs or small trees to come down, for patio furniture and trash cans to blow around, and the potential for sporadic power outages. It takes until Wednesday early to mid afternoon, when the low pressure really starts pulling away, before the wind gusts get down to a more manageable level (under 30 mph).
Our daytime highs for Wednesday will likely happen in the early morning to daybreak hours with strong southerly winds on the backside of the rain and ahead of the cold front. That may warm us into the upper 40s and lower 50s even before sunrise. As we head into the day on Wednesday, clouds hang touch and winds become more northwesterly behind the cold front that shifts through. This drops temperatures back into the upper 30s and lower 40s by the midday and afternoon. As another piece of upper-level energy swings through during the late day and into Wednesday night, a few scattered showers may redevelop over the area. These will be much more light and spotty than tonight's rain activity. As temperatures drop into the mid 30s after midnight, a few of these showers may even mix with isolated snow flurries. Temperatures will remain above freezing, and precipitation will be very light and isolated. We DO NOT expect any issues with those two things in mind.
Whatever flurries or light showers there may be by Thursday morning shift out to the east and northeast as the upper-level system ejects out. Sunshine returns by Friday, but this is short lived as the next weather system approaches over the weekend. Clouds increase going into Saturday, but we look to stay dry through the day and even through a large part of the early to mid evening. A few showers will be possible overnight Saturday night with rain chances maxing out on Sunday as the system moves through. Any lingering showers from Sunday night should be out by Monday, with a break in the rain before the next weather system approaching late Tuesday into Wednesday.