Holidaymakers can expect this summer to be warm but should prepare themselves for frequent downpours, the Met Office said yesterday.

Forecasters expect the summer weather, after the drought of 2006 and the floods of 2007, to return to the more traditional pattern of “three fine days and a thunderstorm”. Temperatures will be higher than average for Britain but in line with the heat associated in recent years with climate change.

“These are the first indications of how the summer will turn out,” said Brian Golding, head of forecasting for the Met Office.

“It’s a long way off but the indications at this stage are that it will be warmer than average. In terms of rainfall we are looking at an indication of above average to average.

“We think it’s likely to be a case of a few fine days and then there’s a band of rain, perhaps some thunderstorms and then it warms up again. The more unsettled spells will perhaps be slightly more frequent than in an average summer.”

Dr Golding said that the rise in temperatures experienced over the past ten years meant that this summer’s likely warmth would come as little surprise.

“It would be very unusual now to be below average,” he added. “Every one of the last ten years has been as warm as the 1971-2000 average or above average for northwest Europe.” Because of the limitations of long-term forecasting the Met Office was unable to offer a reliable forecast for the possibility of extreme events such as heatwaves. These can only be foreseen about a fortnight ahead.

Dr Golding said that there had been “no evidence” to suggest a repeat of last summer’s flooding, but that was equally true in the spring of 2007. Rainfall last summer was the highest on record and left areas of Britain under water.

Two thirds of the 55,000 properties flooded last summer were inundated by high levels of surface water rather than rivers bursting their banks.

The Environment Agency has spent nearly £500,000 in the past nine months creating the first surfacewater maps. These will be provided to local authorities to help them to identify the areas most likely to become flooding hotspots when drains fail. David King, of the Environment Agency, said that the maps offered a “coarse aid” to agencies in preparing against floods.

Rob Varley, of the Met Office, said that the summer forecast was an imprecise science but was a valuable tool to help businesses plan ahead. Utility companies in particular can make use of the “broad brushstrokes” seasonal forecasts in gauging the likely demands on energy needs for heating and levels of demand for water.

Mr Varley said: “We can’t be specific about exactly when the warmer or wetter spells will be – you wouldn’t use the seasonal forecast to decide when to hold your wedding. But we know that every time we issue a seasonal forecast there’s a move in the markets, particularly the energy markets.”