A warm air mass, becoming increasingly warmer, is affecting the area while there will be light dust in the atmosphere from today through to Sunday, the Met Office said in its early morning weather forecast.
Wednesday will be fine and relatively warm with temperatures rising to 35 C inland, around 28 C on the south and east coasts, around 27 C on the remaining coasts and around 30 C in the mountains.
Tonight will be mainly fine. Locally, in the early hours of the morning there may be low cloud or patchy cloud.
Temperatures will fall to 14 C inland and on the west and north coasts, around 16 C on the remaining coasts and around 18 C in the mountains.
Thursday, Friday and Saturday will be mainly fine.
Temperatures will remain at the same levels on Thursday, which are above the seasonal average particularly inland and in the mountains, and will rise even further on Friday and Saturday.