Methods of Weather Forecasting

Method Description
Persistence (Simplest)   Assumes that current conditions persist.  Tends to be very accurate for short periods of time (hours) then accuracy declines.
Steady-State or Trend   Assumes that surface weather systems continue to move as they are now moving without changes in strength.  Quite accurate for few hours
Analogue   Looks for similar situations in the past (especially the recent past).  Forecasts are based on the assumption that system evolution will be the same
         as it has been in similar situations in the past.
Weather Type   Statistical analysis used for long-range forecast up to a month in advance.  Current and recent weather patterns are categorized by type, then dealt  
         with using analogue approach. 
 (Not useful for detailed, short-term forecast.)
Climatological   Based on long-term patterns.  (Not useful for detailed or short-term forecast.)