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Winter Storm Warning Now Through Noon Monday

7 PM — No real changes to the forecast below. Everything seems to be on track. The weather balloon that went up a few hours ago returned data confirming freezing rain/ice will be the initial mode of wintry precip.

The RAP and HRRR weather models predict the freezing rain (beginning of the ice storm) will reach

  • Joelton and Fairview: started around 8 PM.
  • Rivergate/Madison/Bellevue/Downtown/Fairview: right around freezing now.
  • almost all of Davidson Co + Brentwood/Cool Springs near 10 PM
  • Spring Hill/Franklin/Nolensville around 11 PM, and
  • College Grove by Midnight.

Remember, once the icing begins, it’ll take a few hours for it to accrue. Just don’t be the first person to find out “Well, that was all ice.”

These models predict freezing rain to continue until about 3 AM, followed by a one-to-three-hour lull in the precip, and behind that, a blast of snow.

By 6 AM, temps should be in the low 20s. Whatever freezes is going to freeze hard, and hang around most of Monday. Monday’s high: 30.

This website is a supplement to @NashSevereWx on Twitter, where you can find more information.

3:26 PM — Here’s the NWS Conference Call video for all of Middle TN:

2:48 PM Update

Two years ago today, a supercell thunderstorm dropped hail along I-40, causing millions in damage.

From Belle Meade, March 2, 2012:

Today, exactly two years later, we are under a Winter Storm Warning, effective from 6 PM tonight until noon Monday.

Current Official Hourly Observation (taken at :53 on the hour):

Look over toward Memphis. All that will arrive in Middle Tennessee tonight (the algorithm on this map is a little off. It tends to “go blue” [snow] a little too soon. That said, much of this is freezing rain/ice/snow):

As the rain arrives, temps will drop to, then well below, freezing. Our overnight low is 22 (twenty-two).

Winter Storm Warning

Technically, a Winter Storm Warning means:

This warning was issued mainly for ice accumulation.

Ice

As early as 6 PM, rain will be falling, but ground temps will fall to, then quickly below, freezing. Temps next 24 hours (this is auto updating):

Rain will hit the ground, then freeze. This is an Ice Storm.

Freezing rain should begin first in NW Davidson County (Joelton) by late afternoon. This looks like a bad storm for Joelton. The rest of us are forecast to see freezing rain beginning at 6 PM.

Icing will begin at higher elevations first, then spread NW to SE as the night continues.

The NWS expects a total of 0.25″ and 0.40″ of ice.

Those at higher elevations are particularly vulnerable. NW Davidson County (looking at you, Joelton & Fairview), could be on the high side of that total.

If we get this much ice, it will be a significant event. Travel is nearly impossible in 0.25″ of ice.

Power lines and tree branches, weighed down by the weight of the ice, often topple over in these conditions. Prepare for any power interruption. Emotionally ready yourself for the potential we may miss part of the Oscars.

We may also get lightning and thunder with the freezing rain overnight. Yes. ThunderIce.

Once we hit freezing tonight, we won’t get above freezing until noon Tuesday.

Snow

Cold temps will continue to filter into all levels of the atmosphere overnight. During overnight hours, the freezing rain will briefly changeover to sleet, then snow. Sleet (the little noisy pellets) is a good thing, because it will help limit ice accumulation on trees and power lines (but it’ll still contribute to travel problems).

Up to 1″ of snow is expected to fall on top of the ice, all before noon Monday.

Travel

Once temps hit 32, impacts to travel will take a few hours to occur. Because you never want to be the first to say, “Well, that was ice,” I do not recommend travel during the Warning (begins at 6 PM tonight).

Your reports of ice, sleet, snow, and road conditions will be important today. Radar does not see what’s happening on the ground. Tweet in your report simply by including the hashtag “#tSpotter.”

We are uncomfortable giving specific travel advice, and especially uncomfortable on days like this.  Click on this for the TDOT Smartmap for all road condition information. They also have a terrific app.

Any travel north and northwest of Middle TN is discouraged. Even though ice will take a few hours to develop, I would plan to be off the road by 6 PM tonight. Those at elevation will be impacted first and worst. Bridges and overpasses will freeze before “regular” roads. Worst of all, this will happen in the dark. Your built-tough truck cannot handle ice.

We will pass along county/metro school closings, but we find out about those when you do.

Winds

Very strong tonight: 30+ mph gusts are possible, especially tonight. This will enhance/worsen icing impacts, helping to push over any wobbly branches and power lines. Wind chills in the morning will be as low as 9.

After tonight, we are not forecast to rise above freezing until noon Tuesday.  The ice and snow will be around until then.

As always, you can get more/updated info on Twitter @NashSevereWx. Monitor multiple reliable (HINT: not a crap app) weather sources throughout the day.

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