Tropical cyclone warnings
The CPHC issues tropical cyclone warnings in various forms for use by mariners, aviators, and the general public. All tropical cyclone warnings are issued every six hours, and intermediate public advisories are issued every three hours if a watch or warning is current. Special advisories and discussions may be issued at any time if there are significant changes, such as rapid intensification or landfall.
Public advisories are issued for use by the general public and the media. They are written in a format that can be understood by people who are not familiar with meteorological terminology. Public advisories usually contain the following information:
- Position (latitude/longitude and distance from a given landmark)
- Maximum sustained winds in mph (1-minute average) with winds in km/h included in parentheses
- Minimum central pressure in mbar and inHg
- Current motion
If a tropical cyclone is threatening land, advisories may contain information concerning warnings and watches and/or information about storm surge, potential rainfall, or tornadoes.
The forecast/advisory is a version of the public advisory written for use by mariners and the shipping industry. It contains the same information given in the public advisory, and also includes forecast points for 12, 24, 36, 48, 72, 96, and 120 hours from the advisory issuance time. Forecast/advisories also contain wind radius information for gale, storm, and hurricane force winds, as well as 12 foot seas. All wind and motion measurements are given in knots, and all distances are given in nautical miles.
The ICAO advisory is a special advisory written for the aviation industry, for the purposes of routing and safety. It contains the tropical cyclone's current position, maximum winds (in knots), minimum pressure (in hPa), movement, and forecast positions and winds for 12, 18, and 24 hours from the issuance time.
The forecast discussion is a detailed discussion of the state of the tropical cyclone, as well as a technical description of its current condition and environment and forecast reasoning. All discussions contain a table listing forecast positions and winds for 12, 24, 36, 48, 72, 96, and 120 hours from the issuance time.
Tropical Weather Outlook
The Tropical Weather Outlook (TWO) is a brief discussion of current tropical disturbance activity within the basin. It lists significant tropical disturbances and their potential for development in the next 48 hours, as well as any active tropical cyclones. If there are active tropical cyclones, the TWO lists where to find more information on them. The TWO is issued every six hours during the hurricane season (June 1–November 30).
Satellite Interpretation Message
The Satellite Interpretation Message is a summary of all weather within the Central Pacific basin, including any tropical disturbances or cyclones, according to the latest satellite imagery. This product complements the Area Forecast Discussion issued by the NWS forecast office in Honolulu, and covers weather near the Hawaiian Islands in great detail. Satellite Interpretation Messages are issued every six hours.
Area Forecast Discussion
The Area Forecast Discussion (AFD) is issued by the NWS forecast office in Honolulu and not the CPHC itself, but it is the complement of the Satellite Interpretation Message. It provides a technical synopsis of the weather in the vicinity of the Hawaiian Islands, and provides reasoning for short- and long-term forecasts. The AFD also discusses weather warnings and watches (including those for tropical cyclones) and provides a rationale for their issuance, in some cases before they are actually issued.
The CPHC issues regular satellite fixes on tropical disturbances and cyclones in the Central and South Pacific for military and marine interests, and for national meteorological services in the South Pacific. The fixes contain position estimates, movement estimates, and Dvorak analysis of the strength and appearance of the system, usually accompanied by a brief discussion section.
Tropical Cyclone Reports
Tropical Cyclone Reports (TCRs) are post-season reports on all tropical cyclones that existed in the Central Pacific basin during the season. This includes any systems that moved into the basin from the Eastern or Western Pacific basins. TCRs include the following information:
- Storm synoptic history
- Meteorological statistics and data
- Casualties and damages, if any
- Forecast critique and track verification
- Best track data sorted into six-hourly positions
TCRs are issued either near the end of the season or between seasons, and there is no specific time frame for issuance.