Why do most flash flood warnings never happen?

I’m not sure, but maybe it creates dangerous driving conditions? Maybe you just haven’t been able to see it from your home, but nearby streets might be getting inches deep water coverage, which is very dangerous to drive on.

It does matter. It is surprising how little extra rain can make an area flood. And just because it was not flooding where you can see it does not mean it is not flooding anywhere else.

A “flash flood” does not mean something dramatic, like in Minot ND, but it means there may be rapidly moving water and not to attempt to cross it on foot or in a car.

Also, its is a warning, not a certainty.

It’s hardly raining but thundering mostly. My condo is on the second floor and I don’t think I’m in a high flash flood area.

How do I take cover in a second floor condo for a flash flood? (I’m serious)

The flash flood warnings issued on television are just one other media device to get the word out that there is the potential of it happening. Having lived through several, I’d rather be forewarned than oblivious before venturing out.

Regarding your latest post, just listen to the latest news reports, be it radio or television. The second floor of a building doesn’t sound like it is any danger, depending upon where you live.

My mom always worried about me when I had a job that took me to the Federal Reserve bank in downtown Detroit in a bank truck at 3am. “You’re going to get mugged!” she’d say, warning me to be careful. Thank goodness, it never happened! But that doesn’t mean her warnings and worry were useless and didn’t matter. What matters is that since I knew the danger, I was more vigilant and careful, aware of my surroundings, than if I went into the situation all clueless. That alone could have saved my life if someone did try to mug me.

Flood warnings are the same. They’re telling you that the chances are good that you’ll have the right set of circumstances for a possible flood. It becomes like a watery Pascal’s Wager – the cost of awareness and taking cover is generally low, but the cost of getting caught unaware is high. Only in hindsight is the warning “worthless,” but it may also save your life.

It’s for the benefit of those people living or who travel near places that are very prone to high water often. The broadcasters have no way to know the ones who are more at risk so they just do a PSA to get it out there.

Oh I guarantee you it happens in Tucson, AZ, every year during monsoon season (oooh, I can smell it right now… my favorite time of the year in Tucson!!).
They even have something called a “dumb motorists law.” If you go into a flooded street, get washed away, and need to be rescued, YOU pay for all the emergency services that come to pluck your poor ass off the branch you’re clinging to, then you pay because you are a motorist who was dumb enough to test the flash flood. It’s legendary in Tucson.
I’ve seen enough flash floods to stand back, hands up, in total reverence.

If you’re living in an area that has flash flood warnings then you’re getting them because they can happen and probably have happened in your area, and probably do happen from time to time when the conditions are right. “Flash flood” doesn’t necessarily mean that an entire geographical region will be placed underwater (as @zenvelo said, “It won’t be Minot, ND.”), but there are flood channels in your area that are prone to flooding quickly and without warning, sometimes when it’s not even raining where you are.

Again, that’s not like North Dakota, where the floods can often be predicted weeks in advance.

You should learn the geography of your locale, and find the places that do flood so that you can understand why the warnings occur. That way you’ll also know the places to avoid or watch out for when the warnings are given.

The flash flood warnings in my area mention specifically “creeks and low lying areas” then include warnings for motorists. Your condo may not flood, but the road you take to get there might.

My wife grew up in a house that backed up to a small creek, normally there was no water in it but it drained an area large enough that there would be up to 20 feet of fast flowing water when it rained. The water and debris could cause a lot of damage and so her family would have to clear that area each time there was a flash flood warning.

To them, it always applied, to you, it probably doesn’t.

Weather is dynamical system highly sensitive to initial conditions. Small differences yield widely diverging outcomes.

Every year flash flood warnings will a get a little more precise. Doppler radars are capable of detecting the motion of rain droplets in addition to intensity of the precipitation. This data must be linked with local topography which requires enormous computer processing power.