Vietnam Veterans Crash

[Charles L.]

This report from WKRN's Neil Orne...

TRAFFIC BREAKING: Preliminary report exit 8 Vietnam Veterans Blvd closed due to 20 car wreck. No injuries confirmed at this point. Eastbound lanes affected. Dense fog in area at time. First alert enroute and we are hearing from our news stringers in Sumner county of a tractor trailer, bus, and several other cars with a possible pin in. Developing. Will update

And this from WTVF's Leland Statom

Hendersonville Police now say 40 cars in wreck/pile up on Vietnam Vets....1 School Bus may be involved...Dave Nichols is following

Be careful if you are out and about this AM. Bridges and overpasses as well as on and off ramps could be icy.

[Charles L.]

Some Facebook comments say the total number of cars could be well over 100...goodness. Hoping everyone involved is okay, but scanners are going crazy in Gallatin and Hendersonville.

WSMV gave an update and are saying 46 cars were involved, though numerous other reports say over 50 cars were involved. Some minor injuries have been reported. This event happened about 25 minutes ago...black ice and fog are to blame.

[Charles L.]

Good news, none of the students on the bus were hurt. Scanner just went off saying another bus in route to get those students out of that mess.

Lelan Statom is now reporting that one death has been confirmed from this pile-up. He also states that this may not be one "big" pile-up but a mulititude of different pile-ups in the same area.

[jmundie]

There most certainly should have been a freezing fog advisory this morning. The Sillamon Evans Bridge in downtown had been salted, but had clearly been iced over earlier in the morning. My deck and picket fence were coated in ice too.

[Charles L.]

From 107.5 the River...

TDOT is reporting that they hope to have at least one lane back open by 10am. Westbound traffic is open but moving slow due to rubbernecking.

Macon County has sent some emergency response vehicles to help with this situation.

[Charles L.]

WBKO is now reporting that a woman was killed in a crash in Hopkinsville this morning from black ice. Can't stress enough that people need to be careful out there today.

And Justin, no there was no freezing fog advisory issued from neither OHX nor LMK.

[jmundie]

WBKO is now reporting that a woman was killed in a crash in Hopkinsville this morning from black ice. Can't stress enough that people need to be careful out there today.

And Justin, no there was no freezing fog advisory issued from neither OHX nor LMK.

They just released a special weather statement at 8:43 this morning.

OHX dropped the ball on this one, big time. I was wondering last night when dew fell just after sunset (when we were no where near 100% humidity) if we'd have some problems this morning. I didn't expect the overpasses in downtown to be coated with ice though. This is the worst freezing fog event that I can remember. I've seen advisories for much less than this.

Someone was asleep at the wheel... I wonder if people would have been more cautious if news outlets and the nws had notified them there was ice on the roads.

[Charles L.]

The news stations did warn to watch for black ice on bridges and overpasses today...even though no advisory was out.

107.5's latest update...

We're hearing it could be as many as 60 cars. The fog is so thick, it's hard for the authorities to get an accurate count.

News 2 just showed a LIVE shot...zero visibility. Heather Martin also reported that the news van has already developed ice since they arrived on scene, so things aren't improving weather-wise in that area.

[Eric]

They just released a special weather statement at 8:43 this morning.

OHX dropped the ball on this one, big time. I was wondering last night when dew fell just after sunset (when we were no where near 100% humidity) if we'd have some problems this morning. I didn't expect the overpasses in downtown to be coated with ice though. This is the worst freezing fog event that I can remember. I've seen advisories for much less than this.

Someone was asleep at the wheel... I wonder if people would have been more cautious if news outlets and the nws had notified them there was ice on the roads.

I think that's a common misconception...relative humidity is only a measure of how close the air is to saturation, and since it's temperature dependent, it's hardly a good tool to utilize when measuring air parcel saturation.  It just so happened that the air temperature dropped to the dew point last night, and dew formed on those surfaces whose surface temperature was at the dew point.  Subsequently, the air temperature dropped below freezing, and boom..... 

[jmundie]

The news stations did warn to watch for black ice on bridges and overpasses today...even though no advisory was out.

107.5's latest update...
News 2 just showed a LIVE shot...zero visibility. Heather Martin also reported that the news van has already developed ice since they arrived on scene, so things aren't improving weather-wise in that area.

Yeah I just talked to Justin Bruce... he's not sure why a product wasn't issued this am either. Said he and Orne have been hammering freezing fog all morning. I hadn't watched the news. There wasn't any mention of it on NPR

[toastido]

Yeah I just talked to Justin Bruce... he's not sure why a product wasn't issued this am either. Said he and Orne have been hammering freezing fog all morning. I hadn't watched the news. There wasn't any mention of it on NPR

I don't think NPR is where one should turn for local news... Just sayin'

[jmundie]

I think that's a common misconception...relative humidity is only a measure of how close the air is to saturation, and since it's temperature dependent, it's hardly a good tool to utilize when measuring air parcel saturation.  It just so happened that the air temperature dropped to the dew point last night, and dew formed on those surfaces whose surface temperature was at the dew point.  Subsequently, the air temperature dropped below freezing, and boom..... 

Wait, if the air temp is below the dewpoint, does that not mean you have greater than 100% humidity?

[jmundie]

I don't think NPR is where one should turn for local news... Just sayin'

They have a local morning host for a national morning program... much like when local stations do news between the today show or good morning america. They have local features in the morning as well. Traffic, etc.

[toastido]

Wait, if the air temp is below the dewpoint, does that not mean you have greater than 100% humidity?

Humidity (or relative humidity) is the measure of saturation of a particular column of air.  Look at it like water in a glass.

The higher the temperature, the bigger the glass... the more water it can hold.  Now, fill a large glass half full of water.  Now, let's say the temperature begins to drop.  Pour that water into a smaller glass.  It goes from 50% to about 80%.  Temps drop even lower, pour into a smaller glass.  Once you hit 100%, any water that doesn't fit, will fall out of the glass.  You cannot exceed 100% humidity simply because the water will 'fall out' of the column.

The dewpoint is a measure of how small the glass (or how low the temp) has to be for the water to fall out in this example. 

[Eric]

Wait, if the air temp is below the dewpoint, does that not mean you have greater than 100% humidity?

That's where the fog comes from.  Since the air cooled below it's saturation level, the "extra" water vapor condenses to form fog.