Steelbacks skipper Alex Wakely lost the toss and that proved crucial as Warwickshire opted to field.
And with constant rain interruptions, Northants were unable to gather any momentum, losing wickets regularly as they were bowled out for just 151 in a game reduced to 30 overs per side.
Only Rob Keogh (69no) and Josh Cobb (33) provided any real resistance as Warwickshire took control.
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And the holders made it look easy with the bat as the opening pair got them home, with Sam Hain hitting an unbeaten 89 and Will Porterfield 63 not out.
"We just haven’t come out of the blocks at all," said Steelbacks head coach Ripley.
"We had the sharp end of the conditions batting first, we had to stop start and couldn’t get any partnerships together but still our performance is way down from where we expect it to be and we’ve been very well beaten.
“I knew we were well under par but the ball went through a little and I expected our bowlers to be a handful.
"I was hopeful we could pull of something special but we never got started with the ball either so it’s a pretty grim effort all round really.”