Severe Weather Threat 5/19-5/22/2024

[Sawmaster]

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That was snapped/ripped off of the nail with the nail slightly bent, same for another one. I don't know how strong windspeeds need to be for that to happen but that is pretty crazy.

Those are usually secured with 1/2" rebar about a foot long. It's a softish steel where the hammered end tends to spread but doesn't always lock in. Typical weight is 250lbs+ I recall some EF-5 surveys where these were lifted and thrown tens of feet, but the ones in the pic may have already been cracked/ weakened at the stub by parking impacts based on the ones remaining in place and in seeing that kind of damage IRL. I've set maybe 20 of these in my younger days (with a helper of course!)

 

[locomusic01]

Those are usually secured with 1/2" rebar about a foot long. It's a softish steel where the hammered end tends to spread but doesn't always lock in. Typical weight is 250lbs+ I recall some EF-5 surveys where these were lifted and thrown tens of feet, but the ones in the pic may have already been cracked/ weakened at the stub by parking impacts based on the ones remaining in place and in seeing that kind of damage IRL. I've set maybe 20 of these in my younger days (with a helper of course!)

Yeah, the most high-profile instance of this was Joplin, and what was interesting there is the way the parking stops failed. In most cases they seem to have been twisted off counterclockwise with the rebar spikes flattened almost to the ground, and in other cases the spikes themselves were sheared off. Really interesting.

 

[pohnpei]

Those are usually secured with 1/2" rebar about a foot long. It's a softish steel where the hammered end tends to spread but doesn't always lock in. Typical weight is 250lbs+ I recall some EF-5 surveys where these were lifted and thrown tens of feet, but the ones in the pic may have already been cracked/ weakened at the stub by parking impacts based on the ones remaining in place and in seeing that kind of damage IRL. I've set maybe 20 of these in my younger days (with a helper of course!)

The place of these parking stops. Noted that it's outside of the worst damage swath and vehicles nearby not moved

 

[jiharris0220]

The place of these parking stops. Noted that it's outside of the worst damage swath and vehicles nearby not moved

Not surprised to see this as, well obviously the vehicles are a lot heavier than those parking stops.

And of course those things definitely lost some structural integrity since they were installed, most certainly no where near as impressive as the Joplin tornado case.

 

[tornado examiner]

You have extremely powerful wedge tornadoes barely shifting car’s in driveways but then the little parking lot spinups can throw them up into air. So weird how that works…

 

[Sawmaster]

Not surprised to see this as, well obviously the vehicles are a lot heavier than those parking stops.

And of course those things definitely lost some structural integrity since they were installed, most certainly no where near as impressive as the Joplin tornado case.

Even with the car's heavier weight, they are only held in place by friction. The flow of wind under them can reduce their apparent weight, and in most cases only one wheel is locked against rotation. Moving cars is not a big deal- lofting them is. An undamaged parking curb will be more resistant to lateral movement being doubly staked in place with wind not getting under them, and much harder to loft as their weight-to-surface area is much higher than a car.

It's said that in typhoons, flying coconuts are like cannonballs. Getting hit end-on by a flying parking curb in a tornado would be more like an artillery shell's impact.

 

[jiharris0220]

Even with the car's heavier weight, they are only held in place by friction. The flow of wind under them can reduce their apparent weight, and in most cases only one wheel is locked against rotation. Moving cars is not a big deal- lofting them is. An undamaged parking curb will be more resistant to lateral movement being doubly staked in place with wind not getting under them, and much harder to loft as their weight-to-surface area is much higher than a car.

It's said that in typhoons, flying coconuts are like cannonballs. Getting hit end-on by a flying parking curb in a tornado would be more like an artillery shell's impact.

I know, which says a lot about the parking stops in this particular case because they’re the ones that got dislodged while the only vehicle that even got moved a little was the grey pickup.