WARNINGS over dangerously poor air quality have been issued as Scotland prepares for a long-awaited spell of summer, even if the hot snap is scheduled to last little over 48 hours.

With temperatures set to soar to nearly 30 degrees in parts of the country, Friends Of The Earth Scotland has claimed air pollution will rise to beyond safety standards in all but one local authority area.

Meanwhile, one of the country's most prominent medics has urged those with fair skin and parents of young children to ensure they make liberal use of sun protection creams and clothing.

While failing to hit the temperature heights of the south of England, the Moray Firth had some of the best weather in the country on Tuesday while the central belt saw thermometers rise to 25 degrees centigrade.

Throughout Wednesday conditions are predicted to reach up to 28 degrees in Ayrshire, but thunderstorms are likely to follow, with a few days of less warm temperatures by the end of the week.

But Friends of the Earth say the weather will also herald the third air pollution episode of the year, with others having already occurred in April and March.

Emilia Hanna, air pollution campaigner for the campaign group in Scotland said: "The official health advice for the expected levels of air pollution is for people with heart and lung problems such as asthma or emphysema, who experience symptoms, to consider reducing strenuous physical activity, particularly outdoors."

Ms Hanna also warned that while people with existing respiratory problems were at increased risk this week, she called for Government intervention in Glasgow, claiming 300 people die early every year in the city from air pollution.

The predicted heatwave has prompted doctors at the country's biggest health board to issue hot weather advice, particularly for babies, children and the elderly.

Dr Linda de Caestecker, Director of Public Health, at NHS Greater Glasgow and Clyde, said: "A number of Scottish people are fair-skinned and need to take adequate steps to ensure their skin is protected.

"Babies, in particular, need to be covered up. With both sun-creams and sun protection clothing designed for babies and children, there is no need for children to be over-exposed to the sun.

"As Wednesday is expected to be one of the warmest days we have had for a number of years, we need people to be sensible and take precautions which will ensure they stay healthy while enjoying the weather."

She added: "People should try to avoid being in direct sunlight during the hottest part of the day between 12 noon and 3.00 pm.

"Replenishing fluids is really important as everyone runs the risk of becoming relatively dehydrated in this heat and everyone should be particularly careful to take extra liquids, cold tap water is ideal, at regular intervals."

Temperature predictions include Edinburgh enjoying around 25 degrees, while Glasgow could peak at 28 degrees.

Both cities, however, run the risk of rain in the afternoon, with the downpours in Glasgow potentially dramatic.

The Met Office has issued a yellow 'be aware' warning of energised storms of thunder and lightning racing across the south of Scotland by late afternoon.

This could affect a wide area, stretching from Strathclyde, Ayrshire, through Lothian and Borders and down to Dumfriesshire.