temperate

adj. moderate, self-restrained, composed, reasonable

also see Self-controlIn geography, temperate latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally mild, rather than extreme hot or cold. However, a temperate climate can have very unpredictable weather. The north temperate zone extends from the Tropic of Cancer (at about 23.5 degrees north latitude,) to the Arctic Circle (at approximately 66.5 degrees north latitude.) The south temperate zone extends from the Tropic of Capricorn (at approximately 23.5 degrees south latitude,) to the Antarctic Circle (at approximately 66.5 degrees south latitude.)
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Adjective
1. (of weather or climate) free from extremes; mild; or characteristic of such weather or climate; "a temperate region"; "the temperate zones"; "temperate plants"
(antonym) intemperate
(similar) equable
(see-also) clement
2. not extreme in behavior; "temperate in his habits"; "a temperate response to an insult"; "temperate in his eating and drinking"
(antonym) intemperate
(similar) abstemious, light(a)
(see-also) mild
3. not extreme; "a moderate penalty"; "temperate in his response to criticism"
(synonym) moderate
(similar) mild

v. sharpen, temper, mitigate, quench

adj. moderate, temperate, tempered

v. temper, moderate, soften, tone down; spend the summer