Warm Temperate (Mid-Latitude) Climates - C

Warm temperate (mid-latitude) climates sit between roughly 30° and 50° of latitude, mostly along the eastern and western margins of continents. Their defining character is a warm summer paired with a mild winter — not the intense heat of the tropics, nor the bitter cold of higher latitudes. The book splits this broad belt into four distinct types, each shaped by its position on the continent and the air masses that reach it.

The four types are: humid subtropical with a dry winter and hot summer (Cwa); Mediterranean (Cs); humid subtropical with no dry season and a mild winter (Cfa); and marine west coast climate (Cfb). The first three occupy subtropical latitudes, while the fourth sits poleward of them.

Humid Subtropical Climate (Cwa)

This climate appears poleward of the Tropic of Cancer and the Tropic of Capricorn, with the North Indian plains and the interior plains of South China as its main examples. It closely resembles the Aw (tropical savanna) climate, except that winter temperatures are noticeably warmer. The key distinction from the other humid subtropical type is the dry winter — rainfall is concentrated in the warmer months.

Mediterranean Climate (Cs)

The name comes from its classic home around the Mediterranean Sea, but the same climate repeats along the west coasts of continents in subtropical latitudes, roughly between 30° and 40°. Examples include central California, central Chile, and the coasts of southeastern and southwestern Australia.

The mechanism is seasonal: in summer, these areas fall under the subtropical high-pressure belt, which suppresses rainfall; in winter, the westerly winds bring moisture. The result is a hot, dry summer and a mild, rainy winter. Summer monthly averages sit around 25°C, while winter monthly averages stay below 10°C. Annual precipitation ranges from 35 to 90 cm — modest, and heavily skewed toward the winter half of the year.

Humid Subtropical (Cfa) Climate

This type lies on the eastern parts of continents in subtropical latitudes. Here the air masses are generally unstable, and that instability produces rainfall throughout the year — there is no pronounced dry season. The main regions are the eastern United States, southern and eastern China, southern Japan, northeastern Argentina, coastal South Africa, and the eastern coast of Australia.

Annual precipitation averages between 75 and 150 cm. Two rainfall mechanisms dominate: thunderstorms in summer and frontal precipitation in winter. Mean monthly summer temperatures reach about 27°C, while winter means range from 5° to 12°C. The daily range of temperature is small, meaning nights do not cool off dramatically from daytime highs.

Marine West Coast Climate (Cfb)

This climate sits poleward of the Mediterranean climate on the west coasts of continents. Its main areas are northwestern Europe, the west coast of North America north of California, southern Chile, southeastern Australia, and New Zealand.

The marine influence is everything here. Because the ocean moderates temperatures, winters are warmer than the latitude would otherwise suggest, and summers stay cool. Mean summer temperatures range from 15° to 20°C, and winter means from 4° to 10°C. Both the annual and daily temperature ranges are small — the climate is remarkably even through the year. Precipitation falls throughout the year, with totals varying greatly from place to place, anywhere from 50 to 250 cm.