Opting to bat first, Ireland score a competitive 327-5 with Paul Stirling 77, Andrew Balbirnie 135 and Kevin O'Brien 63 the mainstays of their batting and Shannon Gabriel 2-47, the pick of the bowlers for the Windies.
After the experience of conceding a world record opening stand of 365 on Sunday, the Ireland bowlers have plenty to prove.
Balbirnie scored 135 from 124 balls and registered his fourth ODI hundred, passing 3,000 runs for Ireland in the process.
Darren Bravo only made 17 runs before he was dismissed by Stirling.More news: World is losing its 'political will' to fight climate change
File image of Ireland batsman Kevin O'Brien. While Balbirnie smashed 11 sixes and four fours, O'Brien managed three fours and as many maximums. He contributed a more than useful 25 not out from 13 balls, including a big six over mid-wicket from the final ball of the innings.
West Indies open their World Cup campaign against Pakistan in Nottingham on May 31. It was their second highest total against a full member, just one run behind the famous 2011 win over England. Shai Hope, who is has been in terrific form in this series and Sunil Ambris played with great fluency from an early stage and put Ireland on the back foot.
Porterfield's opening partner Paul Stirling will not only be keen to bounce back from his golden duck against the Windies at Clontarf but also get to that elusive half-century which he has failed to do for either Middlesex or Ireland this season despite promising starts. He grabbed his chance though, and was confident right from the start, feasting on some ordinary bowling by Ireland to ensure West Indies' chase never flagged.
The 26-year-old Ambris shared two significant partnerships - with Shai Hope and Roston Chase - to set the foundation for the visitors before Jonathan Carter captain Jason Holder practically formalised the result.More news: HTC flagships getting a slice of Android Pie starting this month
On this day past year, Ireland were preparing to host their first day of Test match cricket, only for rain to delay the historic occasion by 24 hours.
The West Indies captain, Jason Holder came to join the now composed, Carter and they went about knocking off the rest of the runs with a lot of authority.
"I'm very positive that we can bounce back against Ireland, and when we play Bangladesh the second time around, we'll put up a much better performance", Holder said.
Chase made 46, Carter was not out on 43, Holder got 36 and Hope added 30, as the victory meant that the West Indies became the first of three sides to reach the Final which takes place next Friday at this same venue.More news: China retaliates on tariffs, stock markets go into a slide