Page:Weather Facts and Predictions.djvu/33

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of blue are visible the hail will be small, if traces of yellow it will be large.

It was the opinion of Sir J. Herschel that "anvil-shaped" clouds are likely to be speedily followed by a gale of wind.

The most cloudy countries are those where the wind is most variable, as Britain; the least cloudy countries are those in which the wind is least variable, as Egypt.

If small clouds increase, expect rain.

If large clouds decrease, expect fine weather.

Soft filmy clouds indicate fine weather, with light breezes.

Hard-edged clouds, wind.

A dark, gloomy blue sky indicates wind.

A light, bright blue sky fine weather.

The softer and more silky clouds look, the less wind (but perhaps more rain) may there be expected; but the harder, more tufted, more ragged, the stronger the expected wind will be.

Fragments of clouds ("scud") driving across heavy masses of cloud presage wind and rain, but if scud alone is flitting about, the indication may be merely of wind.

Clouds up aloft at great elevations, crossing the sky in a direction different from that indicated on the surface as the direction of the wind, foretell a change of wind towards their direction.

In general it may be said that light, delicate, quiet tints or colours, with clouds of soft, ill-defined outline, indicate and accompany fine weather; but gaudy or unusual hues, with clouds of hard outline, foretell rain and wind.