Glamorgan 183 for 5 (Northeast 60*) beat Gloucestershire 151 for 8 (Charlesworth 45, Hatzoglou 3-23) by 32 runs
Glamorgan struggled at first but Northeast was well supported by Billy Root, Chris Cooke and Timm van der Gugten as they battled to a very challenging total of 183 for five.
Gloucestershire started slowly but looked to be building towards making this game a close one, but the fall of five wickets for 15 runs at the back end of their chase gave Glamorgan the win.
This victory puts Glamorgan level with Hampshire on 10 points and in the mix for a place in the quarter-finals. Gloucestershire remain on just six points and will need to start putting together some results to push for the latter stages.
It was a slow start in the first few overs for Glamorgan with further injuries resulting in another new opening partnership for the home side. This time it was Prem Sisodiya who was given the job at the top of the order with Kiran Carlson. Both openers were gone within the first three overs with Glamorgan reduced to 18 for two.
With Colin Ingram joining the lengthy Glamorgan injury list it was left to Northeast and Root to rebuild. The two shared a stand of 45 that saw them get out of the Powerplay without the loss of any further wickets and with some acceleration.
Root was dismissed for 36 from 24 balls when he was caught at point from a thick outside edge off the bowling of Tom Smith.
Northeast was happy to play the anchor role as players attacked around him and the in form Chris Cooke got off to a flying start on his way to 28 from 17 balls before he became Tom Smith's second victim to leave Glamorgan 116 for four in the 15 over.
An acceleration was needed and that it just want Timm van der Gugten provided as he smoked four sixes on his way to a crucial 38 from 17 balls. His effort was what took Glamorgan to a very competitive total that was tricky when starting your innings.
Northeast was unbeaten at the end with 60 from 48 balls as Glamorgan reached 183 for five, an innings that held together a batting effort from a makeshift top order.
The Gloucestershire innings also got off to a sluggish start, with them reaching the end of the PowerPlay at 44 for one with Miles Hammond the man dismissed for 9 from 11 balls.
Grant Roelofsen had reached 33 from 24 balls when he was caught in the deep by Northeast off the bowling of Sisodiya just as he looked set and was starting to push on to leave Gloucestershire 63 for two in the ninth over.
Another fantastic bit of fielding saw the end of Tom Price when Sisodiya took a catch over his shoulder while running away from the ball off the bowling of Ruaidhri Smith. Van Der Gugten took two wickets in two balls as part of a sequence that saw Gloucestershire go from 113 for three to 128 for eight.
Some lusty blows at the end of the Gloucestershire innings from David Payne gave the visiting fans something to cheer but the result was a heavy defeat against rivals from the other side of the Severn Bridge.