Thunderstorms.

Thunderstorms are most frequent in the districts where the changes of wind are most suddenly felt, from the moist equatorial currents or the cold polar currents of the south-west.

They are most frequent in spring on the west coast, except in the extreme south-west of Otago, where during winter thunderstorms are of almost daily occurrence.

There being no westerly station on that part of the coast, this does not appear in the following abstract :—