It's been a long time coming. The first measurable snow of 2020, and of the meteorological winter season, appears to be on the way. We say appears, because there's an old adage about counting chickens before they're hatched kind of thing, but this looks like a pretty good bet going into tonight. You also don't want to get to crazy with this because you don't like to bet against the trend, which has been for snows to miss us. With all that, we are indeed expecting some accumulating snow here between midnight and about 8 or 9 am.
At this point, we're looking at a 1 to 3 aerial average for the area. A few folks, especially to the east and northeast of Lexington might get a tad more, but for most, the 1 to 3 should hold pretty well. There are SNOW ADVISORIES up for the entire area into the middle of the day Friday. Here's what we expect for impacts...
The window for snow is about 6 to 8 hours with a couple of hours in the middle where the intensity can pick up. Overall, it's a light snow. Obviously as warm as we've been, roads are pretty warm as is the ground. That should also limit accumulations. However as the roads and bridges chill toward morning, slick spots are likely. But this is just a nuisance, you can still get from point A to point B, it will probably just take you longer...so just slow down and plan ahead. A little snow (Advisory criteria) can still cause traffic problems.
So where is this coming from? It's an upper level shortwave rounding the base of the main trough. This will feed into the main surface low that has already been creating havoc with tornadoes and flooding across the South (including SE Kentucky) and the East. The upper low is essentially a burst of atmospheric energy that will drive this whole thing. If you know what you're looking for, it can show up very nicely in some basic products, like radar.
You can see the main storm on the right through the Carolinas and Georgia (and down to Florida and up through the Mid-Atlantic). However, notice the stuff back toward Memphis. Three hours before this image, there was nothing there.
As the low digs around the trough it kicks the dynamics in and creates precipitation that shows up by 9:30. This is a potent upper system with 2 things giving that away. Notice the cluster of convection and heavy rain between Columbus and Tupelo in Mississippi...That's a sign of the dynamics with the system are strong and this digging upper energy will impact the surface low. With the dynamics also comes increased cooling aloft indicated by the growing swatch of snow between Memphis and Jackson, Tennessee. This area will continue to grow and enhance over the coming few hours bringing our first accumulating snow since Veteran's Day.
What's also interesting this season's lack of snow is the historical significance. As of today, we're top of the heap with THE most snowless meteorological winter on record.
It's amazing how quickly we could go from truly historic, to something that while not common, is still not all that noteworthy. With a mere 2 1/2 inches of snow we're out of the top 10 of this list for the first 9 weeks of 'winter'. With 3 inches between now and March 1 we're completely out of the whole winter top 10...that's it...one decent little snow is all that stands between us and a small place in our record books. It's also not like this is a new phenomenon. Five of these top 10 were before 1950. When you look at Lexington's snow history, there are cycles of low snowfalls, but you have to look way back and that's a stat for another time.
So let's hope for a little snow and some patience for the morning commute. Hopefully the roads won't get too bad with this. However, we're not used to it, so slow down, take it easy, increase your following distance etc.
Another little snow is possible mid week (that's an iffy one) and next weekend could also be some fun and games.
Until then, enjoy some of nature's beauty.
Bill
