I've been finding some of the aviation weather products a bit difficult to keep a track of with their times of issuance and validity, so I'm going to try to simplify it here:
METAR: Issued - Hourly
Valid - Time of issuance
TAF: Issued - Every six hours
Valid - 24 - 30 hours
SD (Radar Report): Issued - Hourly
Valid - Time of issuance
FA (Area Forecast): Issued - Every eight hours
Valid - 18 hours
WA (AIRMET): Issued - Every six hours
Valid - Six hours
WS (SIGMET): Issued - Unscheduled
Valid - Four hours (hurricane related six hours)
WST (Convective SIGMET): Issued - Hourly
Valid - Two hours
FD (Winds Aloft): Issued - Every 12 hours
Valid - 24 hours
Surface Analysis: Issued - Every three hours
Valid - Listed
Weather Depiction: Issued - Every three hours
Valid - Time of issuance
Significant Weather Prognostic: Issued - Every six hours
Valid - Listed
Hopefully this will be a good reference for myself and others to come back and look at!
