The higher mountain areas are cooler and moister than the rest of the island. They receive the heaviest annual rainfall, which may be as much as 1,000 millimeters (39.4 in). Sharp frost also occurs in the higher districts, which are usually blanketed with snow during the first months of the year. Precipitation increases from 450 millimeters (17.7 in) up the south-western windward slopes to nearly 1,100 millimeters (43.3 in) at the top of the Troodos massif.
The narrow ridge of the Kyrenia range, stretching 160 km (99 mi) from west to east along the extreme north of the island produces a relatively small increase in rainfall of around 550 millimeters (21.7 in) along its ridge at an elevation of 1,000 meters (3,281 ft). Plains along the northern coast average 400 to 450 millimeters (15.7 to 17.7 in) of annual rainfall.
The least rainfall occurs in the Mesaoria, with 300 to 400 millimeters (11.8 to 15.7 in) a year. Variability in annual rainfall is characteristic for the island, however, and droughts are frequent and sometimes severe. Statistical analysis of rainfall in Cyprus reveals a decreasing trend of rainfall amounts in the last 30 years. Earthquakes, usually not destructive, occur from time to time.
Rainfall in the warmer months contributes little or nothing to water resources and agriculture. Autumn and winter rainfall, on which agriculture and water supply generally depend, is somewhat variable from year to year.