Just one damage report from Saturday afternoon, courtesy of the Nashville National Weather Service.

3:15 PM, 3 miles south of Murfreesboro, power poles snapped, trees “topped out” and out building destroyed

At 3:00 PM in the afternoon, scattered thunderstorms covered parts of Middle Tennessee that are east of I-65.

No warnings have been issued yet (through 3:00 PM) but some of the storms will contain hail and strong wind gusts, in addition to the usual threat of lightning.  The storms are moving east-northeast at 25 mph.

It wouldn’t surprise me if one of the storms in the easter half of the mid-state prompted the National Weather Service to issue a severe thunderstorm warning over the next few hours.

There were some storms around Nashville earlier this afternoon, but right now things are quiet along I-65 and off to the west.

It Ain’t Snow:

Two separate storm cells dump hail in the Clarksville area: the first around 9:45pm, the second at 10:45pm, and another knocking at the door at 11:15pm.

The storms will probably lose some intensity as the front sinks south across middle Tennessee overnight but a heavy downpour, small hail and lightning possible here and there overnight.

A Severe Thunderstorm Watch until Midnight for areas west of Nashville.

Of course, the storm line will also cross Nashville and the rest of middle Tennessee and we will monitor it through the night.

Large hail and strong winds are the most likely threat with this line of storms which should move through during the late evening to overnight hours. Not everyone will receive severe weather but isolated incidents are possible.

Today’s rain comes coutesy of a huge weather system - a veritable blizzard on the northern edge while tornadoes spin up along the southern periphery. A tornado is reported to have caused injuries and damage several large building near New Orleans this morning - imagine how frightening last night was for those in FEMA trailers. There have been active tornado warnings in Mississippi and Alabama this morning but we think the mid-state will only hear a few rumbles of thunder.

View the latest watches from the Storm Prediction Center.

Unfortunate update: one fatality has been confirmed in the Carroltown area, just west of New Orleans proper.

Beginning October 1st of 2007 the National Weather Service will change the way they warn for severe weather. Instead of mentioning entire counties, warnings will target more specific locations. According to the Director of the National Weather Service:

“Storm-based warnings provide the public with more specific information about the location of severe weather and the direction it is expected to move. Seconds count during tornadoes and flash floods. We want to provide the public with the most accurate description of what’s happening in their neighborhood. We also want to avoid warning non-threatened portions of the county.”

When issuing a warning, the NOAA National Weather Service will specify areas within a county and refer to commonly known landmarks such as highways or rivers.

The Fujita scale, used since 1971 to rate tornado strength, changed on February 1st, 2007. The Enhanced Fujita scale is now employed by the National Weather Service to survey storm damage and assess tornado strength. It’s unfortunate that the new scale is already in use; deadly twisters raked Central Florida on the first of the month.

Bobby Knight isn’t the only big name at Texas Tech University - their “Wind Science and Engineering Research Center” is world-reknowned for their wind tunnel work. The Enhanced Fujita scale incorporates their improved understanding of structure damage and its equivalent tornado wind speed.

Although the wind speed ranges have changed with the new scale (see extended entry) the damage that prompted an old F5 ranking still yields an Enhanced Fujita ranking of 5 (EF5). The primary reason to tweak the scale is our increased understanding of the wind damage caused by tornadoes. For historical purposes, old tornado rankings will not be changed.
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The line of thunderstorms stretched to Nashville’s north is slowly sagging southward. At 3:36 am, Clarksville and Erin are on the leading edge of the heavy rain and gusty wind. As we head toward daybreak, I think thunderstorms will remain along and north of I-40. The northwest corner of Middle Tennessee will continue to see the most active weather. A tornado watch continues until 9:00 am this morning, so we’ll monitor the storms closely for any signs of rotation. I think the main problems will be gusty wind on the leading edge of the storms as well as heavy rain due to the slow movement. Some areas in southern Kentucky will contend with flooding due to several inches of rain over the past 24 hours.

A tornado warning continues for Lawrence County until 4:00 pm CDT. According to the NWS it is Doppler-indicated and headed toward Lawrenceburg. Watch Lisa on News 2 for the latest.