Cold-weather alerts: prepare before dangerous temperatures arrive

Cold Weather Advisory · Be aware

Dangerous cold is expected, but below the local warning level

The NWS issues a Cold Weather Advisory when dangerously cold conditions are expected but are not forecast to reach Extreme Cold Warning criteria. Treat it as a prompt to reduce exposure and protect anyone who must be outside.

Check the alert's what, where, and when. Cover exposed skin, dress in dry layers, bring pets inside or provide adequate warm shelter, and shorten time outdoors. Recheck the alert before an early commute, school-bus wait, outdoor shift, or evening event because the coldest period may be overnight or near sunrise.

An advisory is not a mild-weather label. It signals hazardous conditions that deserve precautions even though the office is not issuing its highest cold alert.

Extreme Cold Watch · Be prepared

Extremely dangerous cold is possible, but details are still uncertain

An Extreme Cold Watch means extremely dangerous cold conditions or wind chill values are possible, while the exact occurrence, location, or timing remains uncertain.

Use the lead time. Adjust plans to avoid the coldest period, identify a warm place, check that heat is working, protect vulnerable pipes, and update vehicle and home emergency supplies. The NWS recommends keeping at least half a tank of gas and refreshing a winter car survival kit.

A watch does not guarantee a warning will follow. It means the risk is credible enough to prepare and monitor new forecasts. If the event becomes more certain, the watch may be upgraded; if the forecast changes, it may be modified or canceled.

Extreme Cold Warning · Take action

Extremely dangerous cold is expected or occurring

An Extreme Cold Warning is the action-level cold alert. Avoid going outside if possible. If you must go out, dress in layers, cover exposed skin, tell someone your route and expected arrival, and update them when you arrive.

Do not wait for snow. Dangerous cold can arrive with clear skies, follow a winter storm, or occur with little or no precipitation. The warning is about the cold exposure itself.

During a power outage, the NWS says portable generators belong outdoors at least 20 feet from doors, windows, and garages to reduce carbon-monoxide risk. Follow the warning text and local emergency instructions if a warming center or other service is announced.

Air temperature and wind chill

Cold alerts can be based on either value

Wind chill estimates how cold exposed skin feels because wind increases heat loss. Air temperature is the measured temperature. Current NWS cold products account for dangerous cold with or without wind.

That is why the NWS replaced the former Wind Chill Advisory, Watch, and Warning names in 2024. The current names clarify that very low air temperature alone can be dangerous. Wind chill does not make a vehicle, pipe, or building colder than the actual air temperature, although wind can make those objects cool faster.

Avoid copying a single national number into your plan. Local offices use criteria suited to the area. Read the actual alert issued for your location and pay attention to its forecast minimum temperature, wind chill, start time, end time, and stated impacts.

Outlook, forecast, watch, advisory, warning

Use the product that matches the decision

Outlook

Highlights a broader possibility days ahead. Use it to preserve flexibility and keep checking.

Local forecast

Describes expected temperatures, wind, precipitation, and timing for a point or area. It is routine planning information.

Extreme Cold Watch

Extremely dangerous cold is possible, but important details remain uncertain. Prepare.

Cold Weather Advisory

Dangerous cold is expected below the local warning level. Take precautions.

Extreme Cold Warning

Extremely dangerous cold is expected or occurring. Take action and avoid exposure.

A forecast can show cold temperatures before any alert is issued. A watch can be replaced by a warning, while an advisory may be issued without a preceding watch. Always use the newest official product for your location.

People, pets, pipes, and vehicles

Turn the alert into a short cold-safety checklist

1. Confirm the place and time. Match the alert to your home, destination, and route; note when the coldest conditions are expected.
2. Reduce exposure. Move or shorten outdoor activities, arrange a warm waiting place, and cover exposed skin when going out.
3. Check people. Make a plan for children, older adults, people without reliable heat, and anyone working or traveling outside.
4. Protect animals and property. Bring pets inside when possible, provide unfrozen water, and take steps to prevent pipes from freezing.
5. Prepare the vehicle. Keep fuel above half a tank during extreme cold and carry warm clothes, blankets, a charged phone, water, food, and basic emergency supplies.
6. Recheck before leaving. Read the newest forecast and alert rather than relying on an older screenshot or notification.