Wood left Newcastle to join Forest in a £15 million ($19m) deal in June but had scored only four times for his new club.
The 32-year-old New Zealand international managed just two league goals for Newcastle last term, but he surpassed that meagre total with a treble in 60 minutes at St James’ Park.
Alexander Isak’s first-half penalty put Newcastle ahead, but Wood equalised just before the break.
He struck twice more in the second half to give former Tottenham manager Nuno his maiden victory with Forest in his second game in charge after replacing the sacked Steve Cooper.
It was Forest’s first win in eight games and only their second success in their last 15 matches.
Forest moved five points clear of the relegation zone ahead of the rest of the day’s matches.
Newcastle’s fifth defeat in their last seven games in all competitions leaves them seven points adrift of the top four in seventh place.
Nuno’s first game in charge ended in a painful 3-2 stoppage-time defeat against Bournemouth at the City Ground last weekend.
Newcastle took the lead in the 23rd minute when Sweden striker Isak was tripped in the area by Ola Aina.
Isak picked himself up to squeeze the penalty past Matt Turner for his 10th goal this season.
Anthony Elanga wasted two good chances to equalise when he fired into the side-netting and shot straight at Newcastle keeper Martin Dubravka moments later when a pass to the unmarked Wood looked the better option.
Forest kept battling and they equalised in first-half stoppage-time.
Making amends for his earlier mistake, Elanga was the provider as he took Morgan Gibbs-White’s pass and cut back a low cross that Wood finished from close range.
Forest went ahead in the 53rd minute when Elanga’s superb through-ball reached Wood, who guided a cool finish past Dubravka.
Wood was in the mood and he completed his hat-trick on the hour, surging onto Murillo’s pass and slaloming around Dubravka to slot home.
Luton earned a crucial 3-2 win against relegation rivals Sheffield United thanks to a pair of late own goals.
United were leading 2-1 after goals from Oli McBurnie and Anel Ahmedhodzic overturned Alfie Doughty’s first-half opener for the Hatters at Bramall Lane.
But substitute Morris was the orchestrator as Jack Robinson and Anis Slimane put through their own net to give Luton successive league wins for the first time this term.
Third-bottom Luton are just one point from safety, while United remain bottom of the table.
The clash was also notable for being the first Premier League match to be officiated by a black referee for 15 years as Sam Allison took the whistle.
Bournemouth crushed Fulham 3-0 at the Vitality Stadium to make it four successive wins.
The Cherries went in front late in the first half when Justin Kluivert’s shot squirmed under Fulham goalkeeper Bernd Leno.
Dominic Solanke netted from the penalty spot just past the hour and Luis Sinisterra’s 25-yard rocket capped the rout.
Later on Boxing Day, second-placed Liverpool will climb above leaders Arsenal with a draw or win against second-bottom Burnley.
Third-placed Aston Villa will aim to step up their unexpected title challenge with a victory at troubled Manchester United.
AFP
