Hundreds of anglers who can swing Thursday off work are tipped to enjoy some sunny weather as the new fishing season starts on the Rotorua lakes.
Lakes Tarawera, Okataina and Rotoiti will all reopen on October 1 after a three month closed period over winter, with up to
1000 anglers expected to try their luck.
Most of the fish caught at opening and in the early summer are typically younger fish around two years of age.
Fish & Game officer Matt Osborne said because many of the young fish were released in different months, "there will be a real spread in the size of the catch".
"We believe Okataina will continue the trend seen over the last few seasons and produce the largest fish but this doesn't mean large fish won't be caught on the other lakes."
He said growing conditions for trout in Okataina had been very good in recent years.
"Combine this with lower angler pressure as a result of lake levels and boat launching issues, and you have a formula that means trout can grow to a larger size before they're harvested.
"Two-year-olds caught on Okataina are expected to average around 510mm, while Rotoiti fish will be around the 500mm mark, and Tarawera's a little smaller at 490mm.
"This is due to differences in growth conditions happening between the three lakes."
Mr Osborne predicted Rotoiti would produce the second largest fish and said anglers fishing early in the day should fish fairly shallow.
"Fish will initially be nearer the surface feeding. When the light strengthens, anglers should fish deeper with lead lines, wire lines or jigging.
"If the day remains overcast, fish may remain closer to the surface in some areas, although high boat traffic after the three month break often sends them deeper looking for cover."
Fish & Game officers aim to interview 800 to 1000 anglers on Opening Day for data gathering purposes.
Officers who question anglers on their catches and weigh and measure fish, generally see up to 500 fishers on Tarawera, another 300 at Rotoiti and up to 150 at Okataina, where parking can be limited.
Mr Osborne said with Fish & Game's Fish for Gold promotion underway this year, he hoped to see more anglers fishing on Lake Rotorua too.
A total of 40 red-tagged fish have been released, 10 each, into lakes Tarawera, Okataina, Rotorua and Rotoiti for Fish for Gold.
Anglers who have registered for the event may be lucky enough to win a grand, one-off prize of $25,000, or catch a fish carrying a prize worth $200.
"With the combination of a high catch rate and improvement in the quality of the fish over the past two seasons, Lake Rotorua is a great prospect."
Mr Osborne said the lure of the $25,000 prize would inject some new enthusiasm into the opening, and following 10 day period.
Anglers must have a current licence and register to be eligible. Entries are limited to the first 1200 people to enter, and the deadline to register is September 30.