If you think the warm - nay, stiflingly hot - weather is not normal for this time of year, you're right.

The mercury yesterday rose to 33.1˚C, a full five degrees higher than the 28˚C average for this time of the year (June 11 to 20). That said, the humidity is normal during this change of seasons.

A weather forecaster at the Meteorological Office said that cold air above 10,000 feet in the atmosphere was contrasting with warm air rising from Africa, which then created high altocumulus and cirrus clouds.

The resultant heat is offset by virtue of Malta being surrounded by water. Had it not been so, temperatures would be much higher, the Met Office said.

Overall yesterday was quite dry, the forecaster said. Had the morning humidity continued into the afternoon it would have exacerbated matters.

This weather may also be causing a headache to some people - literally.

Julian Mamo, an expert in Public Health, said most of the problems arose from a lack of sufficient hydration.

"It's common that people don't drink the necessary water immediately, because not everyone perceives thirst in the same manner.

"Because of the humidity, people might not feel dry and yet because of the heat one might still end up dehydrated," he said.

"People who don't drink enough have various symptoms, including tiredness, headaches and palpitations," Dr Mamo said.

Things could be worse for the elderly, he cautioned: "The older you grow, the less control you have on how your body adapts to changes in temperature. If you have heart problems and don't drink enough, it could be the last straw before heart failure."

There are other ways in which the weather could be causing headaches.

The humid heat so prevalent in Malta could aggravate hay fever symptoms, which at times include headaches.

However, it could also be the way arteries reacted to the heat, Dr Mamo explained. The skin arteries open a bit to try and get the body to lose heat but when the ambient temperature is so high the body actually does not manage to lose much heat and this change in the veins might cause a headache.

"It's sort of called a vascular headache, which is, if you like, a cousin to the migraine," Dr Mamo said.

To avoid dehydration, it was best to drink a little amount, often, Dr Mamo advised.

"Some people drink a lot, but they drink a lot just twice a day and for the rest of the day they drink nothing, and in a few hours you can still feel a bit of the symptoms of dehydration."

And with World Cup fever afflicting so many people, the last thing we need is dehydration.