Overall the prevailing wind direction is generally between south and west, but there is often much variation from day to day. During spring south-easterly winds are common, gradually tending towards a northerly direction by early summer. Westerly winds are frequent in summer and autumn and, in winter, southerly winds are the prevailing wind direction. On clear nights in winter the aurora is often observed. Most frequently the display is limited to a glow, arc or arc with rays in which there is only a hint of colour.
Auroral activity varies from year to year with peaks of activity every eleven years.
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