Watch vs warning › Hurricane watch vs hurricane warning
National Weather Service alert guide
Hurricane watch vs hurricane warning
A hurricane watch means sustained winds of 74 mph or higher are possible in your area. Begin preparations. A hurricane warning means those winds are expected. All preparations should be complete.
The lead times are the point. A watch comes 48 hours ahead. A warning comes 36 hours ahead. Both are issued before tropical storm force winds arrive, because once those winds start you cannot safely finish anything outside.
What the National Weather Service says
Hurricane Watch
An announcement that sustained winds of 64 knots (74 mph or 119 km/hr) or higher are possible within the specified area in association with a tropical, subtropical, or post-tropical cyclone.
- Issued by
- The National Hurricane Center.
- How long it lasts
- Because hurricane preparedness activities become difficult once winds reach tropical storm force, the hurricane watch is issued 48 hours in advance of the anticipated onset of tropical storm force winds.
Hurricane Warning
An announcement that sustained winds of 64 knots (74 mph or 119 km/hr) or higher are expected somewhere within the specified area in association with a tropical, subtropical, or post-tropical cyclone.
- Issued by
- The National Hurricane Center.
- How long it lasts
- Issued 36 hours in advance of the anticipated onset of tropical storm force winds.
Tropical Storm Watch
An announcement that sustained winds of 34 to 63 knots (39 to 73 mph or 63 to 118 km/hr) are possible within the specified area within 48 hours.
- Issued by
- The National Hurricane Center.
Tropical Storm Warning
An announcement that sustained winds of 34 to 63 knots (39 to 73 mph or 63 to 118 km/hr) are expected somewhere within the specified area within 36 hours.
- Issued by
- The National Hurricane Center.
Storm Surge Watch
The possibility of life threatening inundation from rising water moving inland from the shoreline somewhere within the specified area, generally within 48 hours.
- Issued by
- The National Hurricane Center.
Storm Surge Warning
The danger of life threatening inundation from rising water moving inland from the shoreline somewhere within the specified area, generally within 36 hours.
- Issued by
- The National Hurricane Center.
Storm surge is a separate alert from the wind alert, and it is the part that kills the most people. Read both.
Watches and warnings are issued ahead of tropical storm force winds, not ahead of the hurricane force winds themselves. You lose your working time before the worst arrives.
Evacuation orders do not come from the National Weather Service or the National Hurricane Center. They come from your state and local officials. If they tell you to go, go.
What to do
If a hurricane watch is issued
- Begin preparations now. You have about 48 hours before tropical storm force winds arrive.
- Find out whether you are in an evacuation zone, and listen for orders from local officials.
- Evacuate if you are told to do so. Leave early, while the roads are still open.
- Fill your gas tank. Get cash. Refill prescriptions.
- Get water and food that does not need cooking or refrigeration.
- Put up shutters or board windows. Bring in anything outside that can become a projectile.
- Charge every phone and battery pack. Get a battery powered weather radio.
- Write down what you need to take with you and where you would go.
If a hurricane warning is issued
- All preparations should be complete.
- Evacuate immediately if you are ordered to. Do not wait for the wind to start.
- If you are staying, get into an interior room on the lowest floor that is not at risk of flooding, away from all windows.
- Stay inside through the whole storm. The calm of an eye is not the end.
- Never run a generator inside a house, a basement, or a garage. Keep it outside and far from windows.
- Do not go into flood water. Do not drive through it.
- Wait for local officials to say it is safe before you go out or go home.
Common questions
What is the difference between a hurricane watch and a hurricane warning?
A hurricane watch means sustained winds of 74 mph or higher are possible in the area, and it is issued 48 hours before tropical storm force winds are expected to start. A hurricane warning means those winds are expected, and it is issued 36 hours out. During a watch you prepare. By the time the warning is issued, your preparations should be finished.
Source: www.nhc.noaa.gov/aboutgloss.shtmlWho issues hurricane watches and warnings?
The National Hurricane Center issues hurricane, tropical storm, and storm surge watches and warnings. Your local National Weather Service office issues the local warnings that come with the storm, such as tornado and flash flood warnings. Evacuation orders come from state and local officials, not from either one.
Source: www.nhc.noaa.gov/aboutgloss.shtmlWhat is a storm surge warning?
A Storm Surge Warning means there is a danger of life threatening inundation from rising water moving inland from the shoreline somewhere in the specified area, generally within 36 hours. It is issued separately from the wind warning because the water and the wind do not threaten the same places. If a storm surge warning covers you, leaving is about the water, not the wind.
Source: www.nhc.noaa.gov/aboutgloss.shtmlWhat wind speed makes a tropical storm a hurricane?
A tropical storm has sustained winds of 34 to 63 knots, which is 39 to 73 mph. At 64 knots, or 74 mph, it becomes a hurricane. Tropical storm force winds are the point where outdoor preparation stops being safe, which is why watches and warnings are timed to their arrival.
Source: www.nhc.noaa.gov/aboutgloss.shtmlShould I evacuate during a hurricane watch?
Evacuate if you are told to do so. That decision comes from your state and local officials, not from the National Hurricane Center, and their orders often come during the watch rather than the warning. If an order covers you, leave early while the roads are still open.
Source: www.nhc.noaa.gov/aboutgloss.shtmlHow a hurricane alert reaches your phone
Hurricane Warnings, Storm Surge Warnings, Typhoon Warnings, and Extreme Wind Warnings are on the National Weather Service list of warnings sent to cell phones as Wireless Emergency Alerts.
Hurricane watches are not. That list is warnings only, so the alert that gives you the most working time is the one your phone will not buzz for. Follow the forecast yourself during hurricane season.
An Extreme Wind Warning means the extreme winds of a major hurricane are about to hit. It means go to an interior room immediately.
Source: www.weather.gov/wrn/weaHow a hurricane alert reaches you when the power is out
NOAA Weather Radio All Hazards broadcasts official Weather Service warnings, watches, forecasts and other hazard information 24 hours a day, 7 days a week, directly from the nearest National Weather Service office.
A battery powered weather radio is the one that still works after the power, the internet, and the cell towers are down. Get it before the season, not during a warning.
Source: www.weather.gov/nwr