HOPE for the best but prepare for the worst — that's the message ahead of the Isle of Wight Festival, with a question mark hanging over the weekend weather forecast.

Local forecaster, Jamie Russell, has told us to expect a warm day with high, thin cloud and hazy sun tomorrow (Thursday), especially as we move into the afternoon.

The IW Met Service forecasts a hot, sunny day on Friday, too, with warm, sunny spells.

More of the same is expected on Saturday morning, but with an increasing shower risk as the day goes on. 

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These may become heavy and possibly thundery in the afternoon.

On Sunday, temperatures are set to drop as the sun makes way for rain. 

"Our confidence after Friday is extremely low at this stage," said Jamie. 

"This is due to a lot of divergence between the weather models, however, it does seem likely that Sunday will be the coolest and most unsettled day of the festival."

The Met Office has forecast light showers throughout Saturday, turning heavy from 4pm, and fluctuating thereafter.

The service expects temperatures to sit at around 18C at midday — a marked drop off from Friday, where temperatures could reach 24C. 

On Sunday, the Met Office is forecasting light rain all morning, but anticipates a cloudy but dry day from 4pm. 

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Temperatures are expected to fluctuate between 16C and 17C in the afternoon, and 12C and 14C in the morning. 

"I want people to really enjoy themselves and to have had the best time for the longest time," said Festival founder John Giddings. 

"Wear clothes that protect you from the rain if it rains. 

"We don't want it to rain, of course, and for the sun you've got to have sunscreen. 

"It's the sunniest place in the UK — the Island. Fingers, arms and legs crossed."

Meanwhile, the Isle of Wight Council is urging festivalgoers to avoid excess alcohol consumption, with a level two heatwave warning in place.

With prolonged periods of warm weather expected over the next few days, a 'heat health' warning has been issued for the Island.