Air Masses classified by temperature and humidity. Tropical: Warm, form in tropics, low pressure; Polar: cold, form near poles, high pressure; Maritime: form over oceans, humid and Continental: form over land, dry. Cold air “undercuts” warm air. If the warmer air mass contains enough moisture, possible storms, clouds, rain followed by clear, cool weather. Warm air “over-rides” cool air. Front moves slowly. If the warmer air mass contains enough moisture, clouds and rain may occur for several days followed by warmer, more humid weather.
Air Masses and Fronts
