More grim evidence of the recession's human cost will come today with figures set to show a further rise in unemployment to a 15-year high of around 2.5 million.

Despite recent signs that the recession may have passed its worst phase, the jobless rate traditionally lags behind and there is more misery on the horizon.

The three months to May saw unemployment rise by 281,000 to 2.38 million and experts are braced for a similar scale of increase in the quarter to June.

Many experts predict dole queues will stretch past the three million mark next year - but an even gloomier forecast from the Centre for Economics and Business Research says it could approach four million.This would be far worse than the 1980s peak under Margaret Thatcher.

The situation is set to grow even more bleak in the months ahead, when a crop of university graduates and school leavers enters the worst jobs market for a generation.

IHS Global Insight economist Howard Archer said: "Youth unemployment is a growing and very real concern.

"Unemployment still looks highly likely to rise above three million in 2010 and we suspect it could eventually peak around 3.2 million."

He warned: "Even if the economy does return to growth in the third quarter, activity is still unlikely to be strong enough for some considerable time to come to prevent further net job losses. In fact, we suspect that unemployment will rise for the rest of this year and much, if not all, of 2010."

Forecasters also predict the number of claimants of jobseeker's allowance rising by 28,000 to 1.59 million in July.

Experts say the claimant count is lagging behind the wider measure of unemployment due to individuals moving off the count on to Government schemes such as the New Deal.