Sunderland were forced to settle for a point at Oakwell after a hard-fought clash in terrible conditions.
The Black Cats were unable to take control of the race for automatic promotion, their long run of scoring in every league game this season coming to an end.
They remain four points off Barnsley but with a game still in hand, their hopes remain very much alive.
They had to survive a first half barrage to come out with a share of the spoils the atrocious weather having a significant influence on proceedings.
Both sides had come into the game defending long unbeaten runs, with Barnsley, like Sunderland, yet to lose at home in the current league campaign.
They started the brighter, finding it easy to play the ball through midfield.
Jon McLaughlin did well to deny them an opener just ten minutes in when Luke O'Nien sold him short with a headed backpass, the ball dropping short and at the feet of Mamadou Thiam, who looked certain to score.
His effort was poor, but McLaughlin had to do well nevertheless to reach up and palm it over the bar.
Sunderland had been forced to make four changes for the game, with Max Power one of those given the nod.
He was given the duty of linking up with Will Grigg and the midfielder came close after the Black Cats built up well down the left. Power turned away from his marker on the edge of the box and fired towards the far corner, Adam Davies doing well to turn it wide.
The elements began to take hold as Storm Gareth rage, a ferocious wind on Barnsley's backs.
They began to establishing dominance over the game, even if it did not translate into clear-cut openings, midfielder Alex Mowatt blasting an effort over the bar from range.
Sunderland were struggling to get out of their half, though Lynden Gooch almost found Grigg at the near post half an hour in, the striker denied by a combination of Barnsley defender Liam Lindsay and Davies.
From there, it was backs to the wall for the away side and they will have felt fortunate and relieved to make it to the break unscathed.
Attacking right-back Dimitri Cavare wasted a good opening when he sent a promising opening high into the away end behind McLaughlin, but Sunderland were carved open when Jordan Green then played a clever pass into the feet of Thiam.
The winger cut back onto his favoured left foot, crashing an effort off the bar.
McLaughlin had to be alert on the stoke of half time when Cavare did find the target from range, the Scot doing superbly to clear with his feet.
Sunderland steadied at the start of the second half, even if Thiam and Mowatt continued to be a threat.
The visitors did forge a big opening an hour in, Jack Baldwin doing superbly to intercept a Barnsley pass, advancing into the opposition half and springing Power free with a pass that split the defence open.
Power fought off the challenge Cavare but could only stab his effort wide of the far post.
All of a sudden Sunderland were on top, going close again as Gooch got the byline and cut the ball back, Lee Cattermole just denied as he tried to turn the ball goalward.
They looked to have been stunned by a sucker punch as Mowatt stood up a cross at the other end, Cauley Woodrow thundering a header into the back of the net.
With Oakwell rising to celebrate, the linesman raised his flag for offside.
The momentum was swinging again and with twenty minutes to go, Jack Ross turned to his bench.
Lewis Morgan came on and quickly wining a corner, Jimmy Dunne volleying just wide.
O'Nien was fortunate when a poor back pass almost caught McLaughlin out, the game entering the final ten minutes evenly poised.
But the game rather fizzled out from there, Barnsley ending in the ascendancy but not calling McLaughlin into action again.
The hosts will have been the happier with a point in terms of the table, but Sunderland will feel they are still within striking distance.
Sunderland XI: McLaughlin; O'Nien, Baldwin, Dunne, Matthews; Leadbitter, Cattermole, Power (Sterling, 90), McGeady; Gooch (Morgan, 75), Grigg
Subs: Ruiter, Ozturk, McGeouch, Wyke, Hume
Barnsley XI: Davies (GK), Cavaré, Pinnock, Lindsay, Pinillos, Green (J Williams, 69), Mowatt, Dougall, Thiam; Bähre (Adeboyejo, 80), Woodrow
Subs: Walton (GK), B.Williams, Jackson, Hedges, Styles
Bookings: Leadbitter, 20 Pinnock, 63 Power, 88