Donaldson, 44, was attempting to become the first person to kayak solo across the Tasman but has been stuck off the Taranaki coast for several days.
Taupo rescue pilot John Funnell, said Donaldson had told them the weather at the moment was the worst he had experienced in his 80-day voyage.
He reported conditions are getting worse with wind gusting up to 100km/h.
Between 5pm and 11pm today the wind is expected to be between 70 and 110km/h.
Mr Funnell said during the night Donaldson, 44, rolled three times and the restraint he uses inside the cabin failed.
He has suffered injuries to his face and chest.
"This is devastating news for his support group and Scott after having spent almost three months at sea paddling the Tasman.
"Scott reports the current weather is the worst thus far he has experienced during the crossing."
