Rain an occluded front, with thunderstorms possible, but usually their passage is associated with a drying of the air mass. Occluded fronts usually form around mature low-pressure areas. What separates rainfall from other precipitation types, such as ice pellets and snow, is the presence of a thick layer of air aloft which is above the melting point of water, which melts the frozen precipitation well before it reaches the ground. If there is a shallow near surface layer that is below freezing, freezing rain (rain which freezes on contact with surfaces in subfreezing environments) will result. Hail becomes an increasingly infrequent
Cork (city) most of which is rain. The airport records an average of 7 days of hail and 11 days of snow or sleet a year; though it only records lying snow for 2 days of the year. The low altitude of the city, and moderating influences of the harbour, mean that lying snow very rarely occurs in the city itself. There are on average 204 "rainy" days a year (over of rainfall), of which there are 73 days with "heavy rain" (over ). Cork is also a generally foggy city, with an average of 97 days of fog a year, most