The alarm was raised on Monday afternoon (July 13), when one of the girls' mothers contacted HM Coastguard.
She realised her daughters, aged nine and ten, were being carried out to sea. According to Selsey RNLI, the mother had ‘tried swimming out to them’ but ‘became exhausted so returned to raise the alarm’.
The girls had launched their paddleboard from the beach near a nursing home, on the western side of Selsey Bill.
Selsey RNLI's D-class inshore lifeboat launched at 4.54pm with three volunteer crew members and made best speed to the scene. Just three minutes later, after rounding Selsey Bill, the crew spotted the girls approximately half a mile offshore.
The RNLI stated: "Both girls were in good spirits but cold and were taken aboard the ILB, supplied with survivor's lifejackets and covered with a waterproof sheet to protect them from the spray."
The children were returned safely to shore, just after 5pm, where they were reunited with their relieved mother, who greeted them ‘with a big hug’. The RNLI said the girls were ‘only suffering a bit from the cold, after their ordeal’.
Selsey Coastguard Rescue Team also attended the incident, in challenging wind conditions.
The charity said the successful outcome was helped by the fact the inshore lifeboat was already on the beach preparing for launch and recovery assessments when the emergency call came in.
"The ILB was at the top of the beach about to start launch and recovery assessments when the pagers sounded, so the launch time was quicker than normal," the RNLI said.
As a result, the girls hadn't travelled as far as the breaking water slightly further out, which ‘could have made it harder for them to stay on the board and more difficult to find’, the RNLI said.
Following the rescue, the RNLI urged people heading to the coast to take extra care, particularly when offshore winds are blowing.
"If you do go to the coast extra care should be taken when the wind is blowing offshore (off the land)," the charity said. "Whatever type of craft you are on it's always best to stay with the craft if you can. Always wear a buoyancy aid."
After the rescue, the family penned thank you messages to the RNLI volunteers.
The volunteer crew comprised Helmsman James Albrey, Harry Emmence and Neil Hopcraft, supported ashore by Richard Brady, Paul Harding and Sam Cato.
5. Two young girls rescued after paddleboard drifts half a mile offshore
After the rescue, the family penned thank you messages to the RNLI volunteers Photo: RNLI Selsey Lifeboat