It was billed as a must-win game for the Steelbacks but the Old Trafford thrashing leaves them all but out of the tournament with two North Group matches remaining.
Northants are three points behind fourth-placed Lancashire, but their run-rate is the worst in the divsion by some distance, and their last eight hopes have all but disappeared.
Things started badly for the County as they lost openers Ben Curran and Ricardo Vasconcelos to loose shots within the opening two overs after Josh Cobb won the toss and elected to bat.
And, a 60-run stand between Rob Keogh (56) and Mohammad Nabi (27) aside, they didn't get much better at any point as a rampant Lightning eased past the Steelbacks' below par 142 for eight with 26 balls to spare.
Finn Allen and Keaton Jennings both posted half-centuries as the Steelbacks bowlers were dispatched to all parts of the ground, with the visitors not helping themselves with a shoddy fielding performance.
Northants had won four of their past five games to give themselves an outside chance of qualification for the knockout stages, but this was a return to the form of the first five matches of the competition, which were all lost comprehensively.
It was a grim night all round, and Ripley wasn't about to make any excuses.
“It’s true that very little went right for us," said the head coach, who led the Steelbacks to the T20 title in 2013 and 2016.
"We lost two wickets at the start and although the partnership between Rob Keogh and Mohammad Nabi was excellent, we still needed a strong finish.
"But instead of that we limped over the line and we were 20 runs short.
"We then needed to start well with the ball, but we didn’t and our skill level was poor in the field.
"We dropped catches, there were overthrows and misfields.
"We didn’t have a lot of luck but the score reflects the gap between the sides.
"With a small target you need to create pressure but them getting to 100 without loss is at the opposite end of the scale.
"We’ve had some good nights of late and I know we are a good team, but we’re just having too many nights when we are low on our skills and of course that’s very frustrating.”
Northants are back in T20 action next Friday when they host Derbyshire Falcons in their final home game of the season at the County Ground, before finishing their campaign against Birmingham Bears at Edgbaston on Sunday, July 18.
Before that, Northants are in LV= Insurance County Championship action against Glamorgan in Cardiff, with the final match of the Group Three campaign starting on Sunday.