"People not taking part in the event are asked to give the competitors plenty of room at the beach and the water for their competition," Harbourmaster Captain Martin Moore said.
Takapau farmer Will Foley said the area had experienced far more rain than what they were used to.
"It's taken everyone a little off guard, we're used to the severe drought conditions that Hawke's Bay usually gets at this time of year, this was all unpredicted.
"In and around October the dry spell is what everyone was expecting so this is something unexpected. In saying that conditions like this are a lot more comfortable to be in.
"It means there's a few little issues to deal with, but nothing insurmountable."
The heavy rain warnings and intense thunderstorm watch weren't enough to dampen the spirits of valient campers Matt, Peggy and and AJ Lawn, who had travelled all the way from Taranaki to enjoy the famous Hawke's Bay sunshine.
"We've had to alter our plans slightly and we've been focusing more in indoor activities thanks to the rain."
"We'll still do all our other activities, we'll obviously just change the order of them. People up here are great, they're really friendly and they've always got ideas when things like this happen."
Hastings had received a total rainfall of 33.8mm from 9am Tuesday to 9am on Wednesday while Napier received 33.0mm.
MetService meteorologist Andy Best said a heavy rain warning remained in place for Hawke's Bay until 1am on Thursday morning.
"An area of low pressure to the northeast of New Zealand directs a moist south to south easterly flow over the North Island.
"An associated front is expected to lie slow-moving over Hawkes Bay and Gisborne, bringing significant rain," he said.
"The heavy rain will fall mainly around the Wairoa district and near the Kaweka Ranges, you can expect about intense falls of about 20-33mm an hour and thunderstorms are also possible.
There is also a moderate risk of thunderstorms and hail throughout the day.
Best said the rainfall could cause streams and rivers to rise as well as surface flooding.
While residents would have to put up with a cool southerly flow with highs reaching 22C, as hard as it was to believe, sunshine was on the way.
"Rain will ease tonight and will gradually turn to showers tomorrow morning. Those cold southerlies will eventually die out."
Thursday would be slightly warmer with a high of 24C, but Friday looked even better with a hot 26C.
"The low to the northeast of the North Island moves away on Thursday, leaving one or two showers over the central and eastern parts of the North Island as it departs.
"The weekend will be even better with highs sitting between 29-30C on Saturday."
