A flash flood warning: what to do first, not wait and see
A flash flood warning means flooding is happening or about to happen, not that it might happen someday, and what to do about it is the whole point of this post. NOAA puts flooding second only to heat among weather hazards for deaths in a typical year, and nearly half of flash flood fatalities happen in vehicles. That last part is the one most within your control. There isn’t time to look things up once a warning is out, so this post is short enough to remember.
Watch, warning, emergency: three different things
The National Weather Service issues a Flash Flood Watch when conditions are favorable for flash flooding, which is your cue to get ready and stay near a radio. A Flash Flood Warning means flash flooding is in progress, imminent, or highly likely, which is your cue to act. There is a third and much rarer level, a Flash Flood Emergency, which the Weather Service issues only when there is a severe threat to human life and catastrophic damage is happening. If you ever hear that one for Hot Springs, move to high ground immediately and don’t finish packing.
Never drive into water on the road
The National Weather Service, citing the CDC, reports that more than half of all flood-related drownings happen when someone drives a vehicle into flood water. Not people caught outdoors, not people trapped at home. People behind the wheel. The Weather Service puts numbers on it: twelve inches of rushing water carries away most cars, and two feet carries away SUVs and trucks. Those figures are the basis of its Turn Around Don’t Drown campaign. Water over a road can also hide a washed-out roadbed underneath, so a stretch that looks like a few inches of standing water might be considerably deeper, or simply not there anymore. If a road is flooded, turn around and find another way, even if that means a longer trip.
Respect barricades, even if the water looks low
A barricade across a flooded road isn’t a suggestion. Never drive around one; it’s there because someone has already assessed that road as unsafe. This matters most after dark, when you can’t judge the depth of standing water by looking at it.
On foot, six inches is enough
Six inches of fast-moving water is enough to knock an adult over, according to the National Weather Service. Keep children away from storm drains, culverts, and high water entirely; they’re pulled off balance more easily than adults and a moment near moving water can turn serious fast.
A flash flood warning: what to do about higher ground and staying informed
If you’re in a low-lying area, along Spring Creek, near the French Broad, or anywhere water tends to pool, move to higher ground as soon as a warning is issued rather than waiting to see how bad it gets. A NOAA weather radio is the backup that works when cell service doesn’t, which during heavy rain in this terrain is often. If you haven’t signed up for alerts yet, the earlier post on French Broad River flood risk walks through that and the river gauge. Pick your high ground before you need it, too: our post on evacuation routes covers choosing ground you can reach on foot when the roads are gone.
After the warning: what comes next
Floodwater that has receded can still be dangerous, contaminated, carrying debris, or hiding a damaged road surface. Stay out of any area that was recently flooded until local officials confirm it’s safe, even if the water itself looks like it’s gone.
The advice in this post is short on purpose. During a flash flood warning isn’t the time to be reading a long list; it’s the time to already know these five things and act on them. Landslides are next, and they follow the same rain that raises the river.
Resources mentioned in this post
- Turn Around Don’t Drown, National Weather Service: https://www.weather.gov/safety/flood-turn-around-dont-drown
- Flooding, Ready NC: https://www.readync.gov/flooding
- Flooding, NOAA JetStream: https://www.noaa.gov/jetstream/thunderstorms/flood
- Flood related products, National Weather Service: https://www.weather.gov/safety/flood-products