WEATHER WATCH

Some old weather saws have more truth than others. Here are a couple worth watching over the next few months ...

Evening red and morning grey, two sure signs of one fine day.

We mentioned once before the general logic behind the old "red sky at night" saying. Because the evening sun travels a long way through the atmosphere, and dust particles scatter light at the red end of the spectrum, a red sky at night suggests a clear sky for a long way to the west which is where our weather comes from. "Morning grey" is the mist that forms on a clear night with a light breeze and dissolves quickly in the warming morning air.

The north wind doth blow, and we shall have snow.

Perhaps. Or, as today's forecasters might well put it, there will be a less than 50 per cent chance of snow. We get north winds either when there is a high pressure ridge blowing in from the west, or low pressure over Europe or the North Sea. In the first case, we would expect generally fine weather with showers only over high ground or in the north. The winter northerlies associated with low pressure over Europe, however, may indeed bring snow, especially in the east and north of the country. The north wind blows at Kew almost 40 days a year. It snows on only ten of them.