Definition!

• Fronts are boundaries between air masses of different temperatures. Fronts are actually zones of transition, but sometimes the transition zone, called a frontal zone, can be quite sharp.
• The type of front depends on both the direction in which the air mass is moving and the characteristics of the air mass. There are four types of fronts: cold front, warm front, stationary front, and occluded front.

(Stationary)

(Warm &Cold)

(Occluded)
• To locate a front on a surface map, look for the following:
  • sharp temperature changes over relatively short distances,
  • changes in the moisture content of the air (dew point),
  • shifts in wind direction,
  • low pressure troughs and pressure changes, and
  • clouds and precipitation patterns.
  (Not all of these patterns may be obvious or even occur, but these are some signs.)