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NWHHC Levels of Alert
  Below, are the types of alerts that the Northwest Hemisphere Hurricane Center will recommend when a tropical cyclone is threatening land. There are seven levels of alert.
These are not official watches and warnings. NWHHC does not issue the official watches and warnings. Instead, we recommend watches and warnings

  Level 1: Tropical Storm Warning: NWHHC will recommend this about 12-15 hours prior to landfall. This will be recommended when a tropical storm is expected to make landfall.

  Level 2: Tropical Storm Warning/Hurricane Watch: NWHHC will recommend a level 2 alert about 12-15 hours prior to landfall. This alert will be recommended when a system is expected to make landfall as a tropical storm, but has an outside chance at becoming a hurricane before landfall.

  Level 3: Hurricane Watch: NWHHC will recommend this alert at least 30 hours prior to expected landfall. A hurricane watch will be recommended when a tropical is expected to make landfall within 30 hours (more lead time will be given as the system increases in intensity), or when a hurricane is expected to make landfall at a different coastal location, but could affect the watch area if the track unexpectedly changes.

  Level 4: Hurricane Watch/Tropical Storm Warning: NWHHC will recommend this level of alert at least 20 hours prior to expected landfall. This is different from a level 2 alert because this is recommended when a hurricane is expected to make landfall in another coastal location, though close enough to bring tropical storm conditions. In addition, residents under this level of alert should prepare for a hurricane warning if the hurricane takes the slightest wobble. A Hurricane Watch/Tropical Storm Warning may also be recommended for a tropical storm which has a greater than 50/50 chance of becoming a hurricane before landfall.

  Level 5: Hurricane Warning: NWHHC will recommend a hurricane warning at least 20 hours prior to landfall (barring any last minute unexpected change in intensity of a tropical storm, forcing a late warning). This is issued when winds of greater than 65KT or tides greater than 7 feet are expected. Residents should consider evacuations and complete all preparations, once a warning is recommended.

  Level 6: Hurricane Warning/Super Hurricane Watch: This is recommended at the same time as a hurricane warning. This has three different meanings. The first is that a category five storm is threatening a coastal location and NWHHC is waiting to narrow down the landfall location before recommending a more urgent warning. The second is that a category five storm is expected to make landfall in another location; however, a change in intensity will bring the category 5 conditions to the location. The third is for a major hurricane which has an outside chance at becoming a category 5 storm prior to landfall. In the event that this alert is recommended, residents need to prepare for massive evacuations and immediately finish all storm preparations.

  Level 7: Super Hurricane Warning: This is the highest level of alert that NWHHC can recommend. NWHHC will recommend this alert at least 12-15 hours prior to landfall (this could be later if a level 6 alert has to be upgraded due to last minute intensification). This is recommended for a very specific area, such as a specific city or a county. NWHHC will only recommend this alert once it has been determined where category 5 conditions are expected. In the event that this alert is recommended, residents should immediately seek shelter, or leave if roads are not congested.

Other Alerts
  Gale and Storm Warnings: NWHHC can recommend gale and storm warnings when a tropical cyclone is expected to bring gale or storm force winds to a particular location, but when the winds are not expected to be directly from the tropical cyclone. In addition, these can be recommended for systems, expected to become tropical cyclones before landfall,, but have not yet developed into a tropical cyclone.



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