Climate of Carnarvon

The climate of Carnarvon is strongly influenced by the southeasterly winds which blow persistently on the northern side of the sub-tropical ridge line. These winds reinforce the normal southerly sea breezes along the coast during much of the year.

In the winter, cold fronts occasionally extend northwards beyond Carnarvon and these together with bands of cloud which originate in the tropics bring some rain. Summer thunderstorms also affect the area. Tropical cyclones or decaying cyclones directly impact on the area infrequently. Rain which falls in the catchment area of the Gascoyne River occasionally causes flooding at Carnarvon but also recharges the aquifers on which the town relies for its water supplies for normal use and for irrigation on farms growing fruit and vegetables.

Most of the annual average rainfall of 233mm falls in the period between May and July, however the infrequent occurrence of tropical cyclones, decaying cyclones or tropical cloud bands between January and July can produce unusually heavy rainfalls. The second half of the year is normally very dry.

Mean maximum and minimum temperatures at Carnarvon range from 33C and 23C respectively in February to 22C and 11C in July. The sea breeze normally moderates summer maximum temperatures near the coast but not inland where they increase sharply.