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Hurricane and Tropical Storm Watches, Warnings, Advisories and Outlooks

Whenever a tropical cyclone (a tropical depression, tropical storm, or hurricane) or a subtropical storm has formed in the Atlantic or eastern North Pacific, the NOAA National Hurricane Center (NHC) issues tropical cyclone advisory products at least every 6 hours at 5 am, 11 am, 5 pm, and 11 pm EDT. Similarly, the Central Pacific Hurricane Center (CPHC) issues tropical cyclone advisory products for the central North Pacific at least every 6 hours at 5 am, 11 am, 5 pm, and 11 pm HST. When coastal tropical storm or hurricane watches or warnings are in effect, the NHC and CPHC issue Tropical Cyclone Public advisories every 3 hours. You can find these products on www.hurricanes.gov for the Atlantic and eastern North Pacific or www.weather.gov/cphc for the Central Pacific; on TV, radio, and cell phones; and NOAA Weather Radio. Information on NWS tropical cyclone watch, warning, advisory, and outlook products is detailed below. For more details on all NHC products, see the National Hurricane Center Product User's Guide. Storm information and forecasts specific to your local area can be found from you local Weather Forecast Office (WFO) through www.weather.gov.

Warnings

Listen closely to instructions from local officials on TV, radio, cell phones or other computers for instructions from local officials. Evacuate immediately if told to do so.

  • Storm Surge Warning: There is a danger of life-threatening inundation from rising water moving inland from the shoreline somewhere within the specified area, generally within 36 hours. If you are under a storm surge warning, check for evacuation orders from your local officials.
  • Hurricane Warning:  Hurricane conditions (sustained winds of 74 mph or greater) are expected somewhere within the specified area. NHC issues a hurricane warning 36 hours in advance of tropical storm-force winds to give you time to complete your preparations. All preparations should be complete. Evacuate immediately if so ordered.
  • Tropical Storm Warning: Tropical storm conditions (sustained winds of 39 to 73 mph) are expected within your area within 36 hours.
  • Extreme Wind Warning: Extreme sustained winds of a major hurricane (115 mph or greater), usually associated with the eyewall, are expected to begin within an hour. Take immediate shelter in the interior portion of a well-built structure.

Please note that hurricane and tropical storm watches and warnings for winds on land as well as storm surge watches and warnings can be issued for storms that the NWS believes will become tropical cyclones but have not yet attained all of the characteristics of a tropical cyclone (i.e., a closed low-level circulation, sustained thunderstorm activity, etc.). In these cases, the forecast conditions on land warrant alerting the public. These storms are referred to as “potential tropical cyclones” by the NWS.
Hurricane, tropical storm, and storm surge watches and warnings can also be issued for storms that have lost some or all of their tropical cyclone characteristics, but continue to produce dangerous conditions. These storms are called “post-tropical cyclones” by the NWS.


Watches

Listen closely to instructions from local officials on TV, radio, cell phones or other computers for instructions from local officials. Evacuate if told to do so.

  • Storm Surge Watch: There is a possibility of life-threatening inundation from rising water moving inland from the shoreline somewhere within the specified area, generally within 48 hours. If you are under a storm surge watch, check for evacuation orders from your local officials.
  • Hurricane Watch: Hurricane conditions (sustained winds of 74 mph or greater) are possible within your area. Because it may not be safe to prepare for a hurricane once winds reach tropical storm force, The NHC issues hurricane watches 48 hours before it anticipates tropical storm-force winds.
  • Tropical Storm Watch: Tropical storm conditions (sustained winds of 39 to 73 mph) are possible within the specified area within 48 hours.

Advisories
  • Tropical Cyclone Public Advisory: The Tropical Cyclone Public Advisory contains a list of all current coastal watches and warnings associated with an ongoing or potential tropical cyclone, a post-tropical cyclone, or a subtropical cyclone. It also provides the cyclone position, maximum sustained winds, current motion, and a description of the hazards associated with the storm.
  • Tropical Cyclone Track Forecast Cone: This graphic shows areas under tropical storm and hurricane watches and warnings, the current position of the center of the storm, and its predicted track. Forecast uncertainty is conveyed on the graphic by a “cone” (white and stippled areas) drawn such that the center of the storm will remain within the cone about 60 to 70 percent of the time. Remember, the effects of a tropical cyclone can span hundreds of miles. Areas well outside of the cone often experience hazards such as tornadoes or inland flooding from heavy rain.

Outlooks
  • Tropical Weather Outlook: The Tropical Weather Outlook is a discussion of significant areas of disturbed weather and their potential for development during the next 5 days. The Outlook includes a categorical forecast of the probability of tropical cyclone formation during the first 48 hours and during the entire 5-day forecast period. You can also find graphical versions of the 2-day and 5-day Outlook at www.hurricanes.gov and www.weather.gov/cphc

NWS Local Forecast Office Tropical Products
  • Hurricane Local Statement: Local NWS offices in areas affected by a tropical cyclone issue Hurricane Local Statements to keep the public, local decision makers, and the media current on potential storm impacts in their area. The Hurricane Local Statement contains a succinct overview of the event and a generalized summary of potential impacts and preparedness information. Potential impact information is ordered based upon the greatest expected impact from the tropical cyclone within the NWS local office’s area of responsibility. Possible sections are wind, storm surge, flooding rain, tornadoes, and other coastal hazards.
  • Tropical Cyclone Threats and Impact Graphics: These graphics provide a threat assessment in terms of potential hazard impacts within an NWS local office's area of responsibility. The assessment scheme takes into account the forecast magnitude of the hazard, along with the associated uncertainty of the forecast. Graphics showing potential impacts from wind, coastal flooding, inland flooding, and tornadoes are produced.