Forest found themselves ahead at the Gateshead International Stadium when Alana Murphy latched onto a short pass by Anna Tamminen before thumping home past the Finnish shot stopper.
However, with ten minutes added on in second-half stoppage time, Nobbs stepped up to be United's hero with a thunderous strike from inside the area, leaving Emily Batty with no chance.
There was a first start of 2026 for Morgan Gautrat as she came into the side for Beth Lumsden, while Kaitlyn Torpey came back into the starting line-up with Jemma Purfield dropping to the bench.
With a whistling wind around the stadium, there was trouble in the air for both goalkeepers and Nobbs' looping effort from 25 yards out had Batty scampering back on her line but the ball dropped just over her crossbar as she crashed into the netting of her goal.
However, the conditions played no part in the opening goal of the game as Murphy intercepted Tamminen's attempted pass out to Emma Kelly before thumping her effort beyond the Newcastle netminder from close range.
A timid first half showing from the Lasses, in which they failed to truly test Batty, almost had a fiery ending just before added time.
Forest failed to deal with a slow cross into their box, with the ball falling at an awkward height to Gautrat, and the American's sliced effort was smartly tipped over by Batty from close range.
United managed to dominate the ball in the second half, forcing Forest to retreat into their defensive third, and were almost rewarded just after the hour mark when, after running onto a Nobbs lay-off, Kelly saw her low effort blocked before it could reach Batty.
Newcastle began to try and take advantage of the afternoon's weather conditions when Nobbs' hopeful and looping cross appeared to miss all her teammates in black and white, but it was well tracked by Batty, who got back on her line to claw away what would've been an equaliser.
As the Lasses continued to push for the equaliser, it was substitute Emilia Larsson who was the most threatening down the left for United.
After picking the ball up in Forest's final third, she darted towards the edge of the box before taking aim and forcing Batty into a diving save that she confidently pushed beyond her post.
With the ball in the box and ten minutes being signalled for additional time, Emily Murphy managed to drop the ball off to Nobbs, who, with the outside of her right foot, fired home from inside the box, leaving Batty with no chance.
After an extended break in play due to one of the assistant referees having to be replaced by the fourth official, it was United who were hunting for a late winner, and Larsson was determined to get on the end of Beth Lumsden's high ball into the box as she rose above Chloe Mustaki, but could only glance her faint header wide.
Newcastle United Women: Anna Tamminen, Charlotte Wardlaw (Demi Stokes 75), Jordan Nobbs, Morgan Gautrat (Molly Pike 86), Emma Kelly (Lois Joel 86), Freya Gregory (Beth Lumsden 59), Deanna Cooper, Kaitlyn Torpey, Oona Sevenius (Emilia Larsson 75), Aoife Mannion (c), Emily Murphy
Subs not used: Hannah Hawkins, Jemma Purfield, Shania Hayles, Małgorzata Grec
