Replacements used: Joe Joyce (Bristol/Exiles) for O'Brien (31 mins), Oisin Heffernan (Lansdowne/Leinster) for Burke (55), Dan Goggin (Young Munster/Munster) for Ringsrose, Frankie Taggart (Belfast Harlequins/Ulster) for Molony (both 63), Denis Coulson (Lansdowne/Leinster) for Dooley (66), Conor McKeon (Lansdowne/Leinster) for Byrne (71). Not used: Jack Cullen (Bruff/Munster).
Replacements used: Ollie Griffiths (Dragons) for Roach, Scott Otten (Ospreys) for E Lewis, Callum Lewis (Blues) for Thomas (all 63 mins), Tyler Morgan (Dragons) for G Smith (65), Rory Thornton (Ospreys) for Sheekey (68), Connor Lloyd (Scarlets) for Williams (72), Luke Garrett (Dragons) for N Smith, Luke Price (Ospreys) for Davies (both 75).
Unfortunately, neither back-line was able to master the very difficult conditions and the best move of a gruelling match saw Garyn Smith put his centre partner Steffan Hughes over for the all-important 62nd minute try.
Ethan Davies, who had earlier kicked Wales into a 9-0 lead, added the conversion to put more than two converted tries between the sides and Ireland's spirited efforts in the final quarter went unrewarded.
A lone Davies penalty midway through the first half was the difference at half-time, and it was looking good for Mike Ruddock's youngsters with only a 3-0 deficit to overturn and the wind behind them.
But Wales' powerful scrum kept them on course, winning a succession of penalties and Davies and captain Hughes combined to eventually put the visitors out of sight.
Wales had the early territory in this top of the table clash in weather-beaten Athlone. Davies watched a third minute penalty tail away to the left, after Ireland captain Dan Leavy was pinged for side entry.
The Welsh out-half then failed to find touch from a second penalty, and Ireland enjoyed a productive 15-phase spell of carrying under the baton of busy scrum half Nick McCarthy.
New winger Cian Kelleher, the only change from the 34-7 win over Scotland, was involved twice as Ireland got into scoring range and kept pressing from a lineout in the visitors' 22.
Prop Peter Dooley got over the gain-line on a muscular burst, but Byrne's subsequent 13th-minute penalty drifted wide on the unforgiving cross-field wind.
Peter Robb, who was guilty of hands in the ruck, breathed a sigh of relief as Davies was off target from a central penalty at the other end.
Forceful carries from Rory Burke and Robb helped to set up a second penalty attempt by Byrne, but once again he sent his effort the wrong side of the right hand post.
Into the second quarter, the wind was more of the factor and Wales used it to their advantage. They won a scrum penalty and the left-footed Davies finally managed to open the scoring by starting the ball to the right of the target and watching it bend back in.
The visitors began to find some reward at scrum time, however Davies suffered a third penalty miss when his driven penalty in the 29th minute curled narrowly wide.
Ireland lost the services of lock Sean O'Brien who injured his left shoulder - a player who they really missed in the forward exchanges. However, Wales missed a chance to add to their lead when a well-struck Davies penalty dropped just short.
Another missed penalty by Davies was chalked down in the 35th minute, with Ireland's defensive workload increasing apart from a Peadar Timmins hack downfield.
It was a hard slog at times for Ireland, for whom Ross Molony had offered a steady supply of lineout possession and a welcome platform to build from.
Despite an early opportunity for Kelleher to attack on the right, the start of the second half belonged to Wales as they won two more penalties off their scrum.
The Welsh pack soon made ominous strides up the left touchline, skipper Hughes threatened in midfield and Davies stepped up to knock over his second three-pointer from close in.
Handling errors blighted Ireland's attempts to respond and they continued to leak penalties as Welsh confidence grew. Davies rewarded his forwards by making it 9-0 with 55 minutes gone.
A storming run from Dooley who made 15 metres deep into Welsh territory got Ireland on the move again, with Joe Joyce, Leavy and Jack O'Donoghue also getting their hands on the ball.
Still, Ireland's scrum issues hurt them again when Ben Roach and Tom Williams set off on an 8-9 move off the base, and the latter followed up to feed quick ruck ball into midfield.
Ireland's defence was stretched in their 22 and with numbers out wide, Garyn Smith released Hughes for a simple finish just to the right of the posts. Davies added the extras and Ireland were now 16-0 behind.
The hosts' frustration grew as the knock-ons and misplaced passes mounted up. Nonetheless, the analysis session will show that Ireland did create chances that could have led to scores in the closing quarter.
From a lineout ball near halfway, Ian Fitzpatrick came off the blindside wing and sprinted through the middle, finally splitting the durable Welsh defence in the 67th minute.
David Busby led the support runners on the right, but the advancing Fitzpatrick failed to capitalise on the overlap as he took contact and knocked the ball on.
Wales managed to close down McCarthy too after a good move down the blindside had catapulted him forward, while Ireland might also have made more of a momentum-building run from replacement prop Denis Coulson late on.
The consolation try never came though, and Wales were well worth their victory in the end with Ireland now looking to bounce back away to defending champions England in two weeks' time.
TIME LINE: 3 minutes - Wales penalty: missed by Ethan Davies - 0-0; 13 mins - Ireland penalty: missed by Ross Byrne - 0-0; 16 mins - Wales penalty: missed by Ethan Davies - 0-0; 21 mins - Ireland penalty: missed by Ross Byrne - 0-0; 25 mins - Wales penalty: Ethan Davies - 0-3; 29 mins - Wales penalty: missed by Ethan Davies - 0-3; 32 mins - Wales penalty: missed by Ethan Davies - 0-3; 35 mins - Wales penalty: missed by Ethan Davies - 0-3; Half-time - Ireland 0 Wales 3; 50 mins - Wales penalty: Ethan Davies - 0-6; 55 mins - Wales penalty: Ethan Davies - 0-9; 62 mins - Wales try: Steffan Hughes - 0-14; conversion: Ethan Davies - 0-16; Full-time - Ireland 0 Wales 16
Referee: Tom Foley (England)