Whitby Charter Skippers, who organise the event, say there is still time to enter the event – the biggest of its kind in the UK – with £1,000 for the runner-up, £500 for third place and £250 fourth.
Daily cash prizes will be up for grabs too.
In the spring festival in April, Paul Barrett of Ripon won the top prize with a 15lb 15oz ling.
But this time, experts believe it could be a halibut topping the scales.
A post from the skippers on the World Sea Fishing forum says there have two halibut caught over the past week or so, with the best clocking the scales at 50lb and another at 36lb.
The Whitby Gazette also featured Carol Hodgson of Dunsley who did battle recently with a 35lb halibut for nearly half and hour before managing to get it on board her boat.
Log on to www.wcsa.co.uk if you would like to enter.
A late summer festival will take place from 28 August to 11 September.