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Mists often appear sooner on parts of hills covered with trees than elsewhere. This happens especially when the mist begins to form after midday, because then the temperature of the trees is lower than that of the grassy slopes. Similarly, mists often linger longest over forests, probably on account of the comparative cold of forest air, arising from the large evaporating surface presented by the leaves of the constituent trees, which, be it remembered, are all the while enshrouded in mist.

Cloudy mists forming or hanging on heights indicate, if they endure, increase, or descend, that wind and rain are coming, but if they rise or disperse fine weather may be looked for. A morning mist which breaks up into soft looking cumuli clouds betokens a fine day.

Frequent mists foretell rain.

A gloomy mist especially presages rain. [The gloominess is owing to the presence of black clouds over head, which will supply the rain.]

Mists in autumn are often followed by wet; in spring seldom.

If in summer towards dusk, a mist is seen to rise from a stream or a meadow, the next day will be warm.

If a mist appear before sunrise about the time of full moon, fair weather for some days may be expected.

Mists are usually observed with barometrical extremes—very high or very low pressure. [A high barometer testifies to a period of calm,