What is the difference between a watch and a warning?

A watch means conditions are favorable for dangerous weather over a large area in the coming hours — be prepared. A warning means the dangerous weather is occurring or imminent for a specific, smaller area — take action now. The mnemonic: a watch is the ingredients on the counter; a warning means the storm is already cooking.

What is the difference between a tornado watch and a tornado warning?

A tornado watch (issued by the Storm Prediction Center) means tornadoes are possible across a region in the next several hours — review your plan and stay alert. A tornado warning (issued by your local NWS office) means a tornado is indicated by radar or has been spotted for your specific area — get to your safe place immediately.

Who issues weather watches and warnings?

Watches cover large regions and long lead times, so tornado and severe-thunderstorm watches come from the national Storm Prediction Center (flood watches from the Weather Prediction Center). Warnings are local and time-critical, so your nearby NWS Weather Forecast Office issues them as a tight storm-based polygon.

Is a warning worse than a watch?

Yes. A watch is the earlier, lower-urgency step (conditions are possible); a warning is the escalation (the hazard is occurring or imminent). The watch almost always comes first, and not every watch produces a warning.

Watch vs Warning — Tornado, Severe Thunderstorm & Flash Flood

Watch vs Warning — Tornado, Severe Thunderstorm & Flash FloodA watch means conditions are favorable for dangerous weather (be prepared); a warning means it is happening or imminent (take action now). Who issues each, and the difference for tornado, severe thunderstorm, and flash flood.A watch means conditions are favorable for dangerous weather — be prepared. A warning means the dangerous weather is happening or about to happen — take action now. The classic mnemonic: a watch is like the ingredients being out on the counter; a warning means the storm is already cooking.The three levels

Watch: Conditions are possible within a large area over the next several hours. Issued by the Storm Prediction Center for tornado and severe-thunderstorm watches. Review your plan and stay alert — do not shelter yet.

Warning: The hazard is occurring or imminent for a specific, smaller area (a "storm-based" polygon). Issued by your local NWS forecast office, triggered by radar or a spotter report. Act immediately.

Advisory: A step below a warning — conditions expected to cause inconvenience or some hazard (a Wind Advisory or Frost Advisory, for example) but not the threat-to-life level of a warning.

Who issues whatWatches cover big regions and long lead times, so they come from the national Storm Prediction Center (tornado and severe-thunderstorm watches) or the Weather Prediction Center (flood watches). Warnings are local and time-critical, so your nearby NWS Weather Forecast Office issues them as a tight polygon. The watch almost always comes first; the warning is the escalation, and not every watch produces a warning.The common types, lowest to highest urgency

Tornado Watch then Tornado Warning: Watch means tornadoes are possible across the region; warning means a tornado is indicated by radar or has been spotted — get to your safe place now.

Severe Thunderstorm Watch then Warning: Severe means 1-inch or larger hail or 58+ mph wind. A warning means a storm meeting that criteria is bearing down on your area.

Flash Flood Watch then Warning: Watch means heavy rain could cause flooding; warning means flooding is happening or imminent — never drive into water.

The fastest way to receive warnings is a NOAA Weather Radio or BloomWX push notifications.

Frequently asked questions

What is the difference between a watch and a warning?: A watch means conditions are favorable for dangerous weather over a large area in the coming hours — be prepared. A warning means the dangerous weather is occurring or imminent for a specific, smaller area — take action now. The mnemonic: a watch is the ingredients on the counter; a warning means the storm is already cooking.
What is the difference between a tornado watch and a tornado warning?: A tornado watch (issued by the Storm Prediction Center) means tornadoes are possible across a region in the next several hours — review your plan and stay alert. A tornado warning (issued by your local NWS office) means a tornado is indicated by radar or has been spotted for your specific area — get to your safe place immediately.
Who issues weather watches and warnings?: Watches cover large regions and long lead times, so tornado and severe-thunderstorm watches come from the national Storm Prediction Center (flood watches from the Weather Prediction Center). Warnings are local and time-critical, so your nearby NWS Weather Forecast Office issues them as a tight storm-based polygon.
Is a warning worse than a watch?: Yes. A watch is the earlier, lower-urgency step (conditions are possible); a warning is the escalation (the hazard is occurring or imminent). The watch almost always comes first, and not every watch produces a warning.
What is a weather advisory?: An advisory is a step below a warning. It means conditions are expected to cause inconvenience or some hazard — a Wind Advisory or Frost Advisory, for example — but not the threat-to-life level that justifies a warning.

Part of the BloomWX learn library — beginner-friendly explainers covering every surface of the BloomWX weather dashboard. Open BloomWX to see live data for any U.S. county.