What to do in the last five minutes.
Five hazards. Plain-language actions for people making a decision now — not a weather explainer, not a policy document.
In a life-threatening emergency, call 911 (US & Canada) — this site is not a substitute for the official warning.
Get low. Get inside. Get away from windows.
A tornado watch means conditions are right. A tornado warning means one has been seen or is on radar — act immediately.
- →Move to the lowest floor, an interior room, no windows — a bathroom, closet, or basement.
- →Cover your head and neck with your arms and put something heavy over you — a mattress, blanket, or helmet for kids.
- →In a mobile home or car, abandon it. Get into a sturdy building or lie flat in a low ditch, hands over head.
- →After: watch for downed power lines and gas leaks. Do not use candles for light indoors.
Turn around. Don't drown.
Six inches of moving water can knock you off your feet. Twelve inches can carry a car. Most flood deaths happen in vehicles.
- →Never drive through a flooded road, even a familiar one. The road under the water may be gone.
- →Move to higher ground. If you cannot, go to the highest level of the building — but never a closed attic.
- →Unplug electronics before water reaches outlets. Cut power at the breaker only if it is safe and dry to do so.
- →After: assume standing water is contaminated. Do not use tap water for drinking or brushing teeth until officials clear it.
Heat kills more people than any other weather.
Heat exhaustion escalates to heat stroke fast — especially in humidity, in older adults, in children, and in anyone without AC.
- →Stay indoors during the hottest hours (roughly 11:00–17:00). A public library, mall, or cooling centre is safer than an unair-conditioned home.
- →Drink water before you feel thirsty. Skip alcohol and heavily caffeinated drinks.
- →Check on neighbours over 65, anyone on chronic medication, and anyone without AC — twice a day during a heat dome.
- →Heat stroke = confusion, hot dry skin, no sweat, or a temperature over 40 °C / 104 °F. Call 911 or 9-1-1 immediately.
The cold is patient. Prepare before it arrives.
Blizzard, ice storm, and wind-chill warnings each carry different risks — from car strandings to frostbite in minutes.
- →If travel is not essential, don't. Highways can close without warning; ditches fill with drifting snow.
- →Keep a car kit: blanket, phone charger, water, snacks, shovel, sand, warm gloves. If stranded, stay with the vehicle.
- →Frostbite can start in under 10 minutes when the wind chill is below −27 °C / −17 °F. Cover every inch of skin.
- →Never run a generator, grill, or gas stove indoors for heat. Carbon monoxide is silent and fast.
Fit matters more than brand.
An N95, KN95, or KF94 filters most fine wildfire particles (PM2.5) — but only if it seals against your face. Cloth and surgical masks do not.
- →Wear a respirator outdoors when the AQHI is 7+ or the AQI is above 150.
- →Close windows. Run AC on recirculate. If you have a portable HEPA purifier, size it for one room and stay in that room.
- →Skip outdoor exercise. Skip open windows in the car — set climate to recirculate.
- →Chest tightness, wheezing that won't ease indoors, or blue lips or fingertips: seek care. Call your local health line first if you're unsure.
Canada reads the air as a health risk. The US reads it as a concentration.
The AQHI is a 1–10+ index blending ozone, NO₂, and PM2.5 into a health-risk score. The AQI reports the single worst pollutant's concentration on a 0–500 scale. A "moderate" reading in one country does not map cleanly to the other.