UPDATE - 10:00am Sunday, March 3rd, 2019
A Winter Weather Advisory has been issued for northwest Tennessee until 1 o'clock this afternoon.
UPDATE - 8:30am Sunday, March 3rd, 2019
Last week, the models remained all in agreement that it looked like snow would fall mostly along the Tennessee-Kentucky state line and cause few issues near I-40 in West Tennessee. Very slowly, those models have gradually brought colder and colder air into West Tennessee farther and farther south. It's starting to look as though not only could parts of West Tennessee get "grass-covering" snow but also more of the area could see snow altogether.
The backbone of this forecast comes down to "where will the center of low pressure travel?" Colder air is on the north side of the low and warmer air is on the south side, so the farther south that feature goes, the farther south the cold air goes! This graphic shows a group of models trying to pin down where the low would be, and most now show central Mississippi.
There has been a gradual trend in the data that this low is going farther south allowing for colder air to invade more of West Tennessee. So let's actually look at the numbers and see what the 8 a.m. temperatures are.
The backbone of this forecast comes down to "where will the center of low pressure travel?" Colder air is on the north side of the low and warmer air is on the south side, so the farther south that feature goes, the farther south the cold air goes! This graphic shows a group of models trying to pin down where the low would be, and most now show central Mississippi.
There has been a gradual trend in the data that this low is going farther south allowing for colder air to invade more of West Tennessee. So let's actually look at the numbers and see what the 8 a.m. temperatures are.
Temperatures are cold everywhere but they're already only 2°F above freezing in northwest Tennessee, so snow may begin to fall there sooner than expected. Now, the low pressure is going to move slow, so we aren't expecting the temperatures to fall below freezing, for example, in Jackson until later tonight. This 24-hour forecast temperature chart shows below-freezing temperatures at 9 o'clock this evening.
But we don't necessarily have to have below freezing temperatures for snow to fall. Some parts of West Tennessee near the Tennessee-Kentucky state line will see snow first, and then gradually that rain-snow line will move farther south. Right now, radar is already estimating that a wintry mix is coming down over northwest Tennessee.
This will be the tricky part, as we'll depend on your observations to see where the snow is actually hitting the ground. Radar data is often only showing us what kind of precipitation is falling a mile up in the sky and not what is reaching the surface. Please keep me posted on what you're seeing via social media!
As far as totals go, that's going to be tricky too. Take this model for example - it shows a narrow band of 1"-2" of snow falling in West Tennessee just north of I-40.
However, there are still some factors limiting this from actually happening - the ground is too warm and the air temperatures will not drop fast enough for what falls to stick. We may very well have a band of 1-2" of snow fall in northwest Tennessee today but that's going to happen anywhere, it's likelier near where temperatures are already near freezing.
Please keep us posted on what you're seeing today as that will help us update the forecast! The snow is currently expected to stop this afternoon with a few light snow showers possible this evening. Then we're going to look at the potential for "flash freezing" tonight with below freezing temperatures causing slick roads in West Tennessee!
But we don't necessarily have to have below freezing temperatures for snow to fall. Some parts of West Tennessee near the Tennessee-Kentucky state line will see snow first, and then gradually that rain-snow line will move farther south. Right now, radar is already estimating that a wintry mix is coming down over northwest Tennessee.
This will be the tricky part, as we'll depend on your observations to see where the snow is actually hitting the ground. Radar data is often only showing us what kind of precipitation is falling a mile up in the sky and not what is reaching the surface. Please keep me posted on what you're seeing via social media!
As far as totals go, that's going to be tricky too. Take this model for example - it shows a narrow band of 1"-2" of snow falling in West Tennessee just north of I-40.
However, there are still some factors limiting this from actually happening - the ground is too warm and the air temperatures will not drop fast enough for what falls to stick. We may very well have a band of 1-2" of snow fall in northwest Tennessee today but that's going to happen anywhere, it's likelier near where temperatures are already near freezing.
Please keep us posted on what you're seeing today as that will help us update the forecast! The snow is currently expected to stop this afternoon with a few light snow showers possible this evening. Then we're going to look at the potential for "flash freezing" tonight with below freezing temperatures causing slick roads in West Tennessee!
We'll have the latest forecast on WBBJ 7 Eyewitness News at 5:30pm. I'll update social media throughout the day as well.
SUMMARY
- Air temperatures are near freezing in northwest Tennessee and overall, temperatures are colder than expected
- It's possible that with below freezing temperatures there soon, we may see a quicker change over to a wintry mix or snow
- The rain-snow line will gradually travel south this morning and afternoon with the snow expected to stop this afternoon followed by a few light snow showers this evening
- See the graphic just above for forecast snowfall totals
Thank you Tom for our weather update. I live in Dyer looks like we are right on the spot for snow. Hope you have a great day.
ReplyDeleteDebbie
Sleeting in Rutherford!
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