A mackerel sky
Is very wet, or very dry.
Still it is really to the wind that the gardener looks most, and if he have a weathercock in his garden (which with a sundial, a rain gauge, and an outside thermometer he should always have) he will note each turn of the wind. If he has no weathercock then he will read the wind by the smoke of chimneys, or the turn of the leaves of trees.
And, after regarding the wind, he may remember this:
When it rains with the wind in the east,
It rains for twenty four hours at least.
And this also:
When the wind is in the south,
’Tis in the rain’s mouth;
When the wind is in the east