What to do before, during, and after the storms that matter most — tornadoes, severe thunderstorms, flash floods, and the rest. Read it on a calm day so you already know the plan when a warning goes out.
Weather that is inconvenient or hazardous, but not expected to be life-threatening if you use caution.
Be careful.
Conditions are favorable for the hazard to develop. Nothing has formed yet, but it could.
Be prepared. Review your plan.
The hazard is happening now or is imminent in your area, detected by radar or confirmed by observers.
Take action immediately.
A Particularly Dangerous Situation (PDS) tag, a Tornado Emergency, or a Flash Flood Emergency is reserved for rare, extreme events where catastrophic damage and loss of life are likely. If you hear those words, act without hesitation.
A tornado is occurring or imminent. You may have only minutes.
Go to the lowest floor you can reach quickly, into an interior hallway or stairwell away from windows. Do not use the elevator — power may fail.
Follow the building's tornado plan. Move to designated shelter areas, typically interior hallways or rooms on the lowest floor.
Leave. Even tied-down mobile homes offer little protection. Go to a sturdy building or storm shelter before the storm arrives — this is why you plan ahead during a watch.
If you can safely drive to a sturdy building, do. If you are caught, either stay buckled with your head below the windows and covered, or — if you can get noticeably lower than the road — leave the car and lie flat there, covering your head.
Lie flat in a ditch or the lowest ground you can find, face down, covering your head with your arms. Stay away from trees and vehicles, which can become projectiles.
Do not shelter here. Overpasses funnel and accelerate wind and debris, and they are one of the most dangerous places to be.
Outdoor warning sirens are designed to alert people who are outside. You may not hear them indoors, asleep, or over a storm. Keep at least two ways of receiving warnings, such as your phone and a NOAA Weather Radio.
Damaging wind of at least 58 mph, hail one inch or larger, or both.
The National Weather Service adds a tag to the bottom of severe thunderstorm warnings to show how serious the storm is. The higher tags are the ones to take especially seriously.
| Tag | Threshold | What it means for you |
|---|---|---|
| Base warning | 58+ mph wind or 1″+ hail | Tree limbs down, some roof and siding damage, dents from hail. |
| Considerable | 70+ mph wind or 1.75″+ hail | Trees uprooted, significant structural damage likely. Treat it seriously. |
| Destructive | 80+ mph wind or 2.75″+ hail | Widespread severe damage. This tag sends an alert to phones. Shelter as you would for a tornado. |
Severe thunderstorms can produce tornadoes, sometimes before a tornado warning is issued. If you see rotation, hear a loud roar like a freight train, or a warning mentions a possible tornado, go to your tornado shelter.
Flash flooding is happening or about to. Water can rise in minutes.
of moving water can knock an adult off their feet.
of moving water can float and carry away most cars.
of moving water can sweep away SUVs and pickup trucks.
Most flood deaths happen in vehicles. You cannot tell how deep the water is or whether the road beneath it has washed out.
When a Flash Flood Warning carries a considerable damage threat: do not attempt to travel unless you are fleeing an area subject to flooding or under an evacuation order. A Flash Flood Emergency means catastrophic flooding and an extreme threat to life.
Every thunderstorm produces lightning, whether or not it is severe.
Call 911. Lightning victims carry no electrical charge and are safe to touch. Begin CPR if the person is not breathing, and use an AED if one is available.
Ice, snow, and dangerous cold — including hazards that start indoors.
Numbness and white, grayish-yellow, or waxy-feeling skin, usually on fingers, toes, ears, or nose. Warm gradually — do not rub the area.
Shivering, confusion, slurred speech, drowsiness, and exhaustion. A body temperature below 95°F is a medical emergency — call 911.
Heat kills more Americans each year than any other weather hazard.
Heavy sweating, cool clammy skin, weakness, nausea, dizziness. Move somewhere cool, loosen clothing, sip water. Get medical help if symptoms worsen or last over an hour.
High body temperature, hot red skin that may be dry or damp, confusion, or loss of consciousness. Call 911, then cool the person with cool cloths or a cool bath. Do not give them fluids to drink.
Storms knock out power. The dangers often come from how people cope with it.
Never run a generator inside your home, garage, basement, or crawlspace — even with doors and windows open. Keep it at least 20 feet from the house, with the exhaust pointed away from doors, windows, and vents.
Put together enough to get your household through at least three days on its own. Keep it somewhere easy to grab — ideally in or near your tornado shelter spot.
Make a plan, too. Agree on where your household shelters for each hazard, how you will reach each other if separated, and one out-of-town contact everyone can check in with. Practice your tornado drill at least once a year so it is automatic when it counts.
Guidance based on recommendations from the National Weather Service, CDC, FEMA, and the American Red Cross. Always follow instructions from local officials during an emergency.