Heading

1) True Course (TC): This is the course measured from your navigation plotter when you plot your flight on your map.

2) True Heading (TH): Now that you have a true course, we need to correct for winds which will give us a true heading. 

3) Magnetic Heading (MH): The difference between true north and magnetic north is known as variation. By adding or subtracting variation from your true heading you will get your magnetic heading

4) Compass Heading (CH): Items from inside the airplane can actually affect the performance of the compass. These errors are referred to as deviation. 

Aviation Weather

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!