Sea bathers have been warned to be on their guard this week after recent rough conditions led to two boys being swept into trouble off the Norfolk coast where waves of nearly 23 feet were reported and lifeboat crews risked their lives to help.

As the school summer holidays get under way, experts are urging people to be aware that the sea may not be as calm as visitors might expect in July and August.

The boys, aged 11 and 12, were rescued from the beach near Waxham on Sunday afternoon when they got swept out by choppy seas which then threw them back on to the sands.

One had gone to the aid of the other, who had been dragged out in rough seas with a heavy swell and winds gusting to force six. They were airlifted to the James Paget University Hospital at Gorleston for check-ups.

Among the emergency services scrambled to help were lifeboats from Happisburgh and Sea Palling which both launched but turned back before reaching the scene because the children were reported safe.

Sea Palling spokesman Lewis Gladding said conditions for the crew had been “hard core” with a swell of six to seven metres (19-23 feet), and occasional breaking waves. He added: “They were definitely putting their lives on the line – it was very scary out there.”

Happisburgh spokesman Philip Smith said they had cancelled their normal practice session that morning because of the conditions and could only launch their bigger boat, for safety reasons, when they received the emergency call.

“These conditions of wind and tide are more common in December and January,” he said “When these big breakers come in people should stay out of the water and enjoy the thrill from a safe place.”

Happisburgh lifeboat’s first attempt to dock with its trailer on returning to base failed when the trailer was washed to the side by the waves and almost turned onto its side.

A coastguard spokesman said a strong onshore breeze had been blowing from the northwest from at least Friday morning, producing a strong offshore swell which created dramatic surf as it came ashore.

Although it was enjoyed by experienced surfers, it could be a hazard to users of inflatable boats and toys if a strong undertow was created. She urged people to check tide and weather conditions before setting out for the beach, and to stay within their capabilities

alex.hurrell@archant.co.uk