Sowerby played some attractive football in the early stages and they took the lead after 10 minutes when good work between Karl Wooliscroft and Rajko Jovanic released John Wilkinson, whose fine pass picked out Lee Barber to score with the coolest of strikes.
The Nest defence stood firm after that and the hosts went in search of the equaliser after the break.
Dan Taylor, Adam Kershaw and Tim Backhouse defended well but Nest missed two glorious chances to level and Adie Gawthrope produced a stunning save to keep out Jason Armstrong's header.
Sowerby weathered the storm and a John Punda free kick caused panic, Armstrong flattening Lee Barber and John Wilkinson scored from the resulting penalty. Wilkinson was lively and wrapped up the win when he latched onto Jovanovic's fine pass to race away and score a great individual goal.
Northowram went above Martins Nest into fifth thanks to a 2-1 win away to Hebden Royd Red Star Reserves.
Mark Eade and Danny King, scorers of 13 of the team's last 14 goals, were each on target as the Rams survived a shaky final 10 minutes for a deserved success.
The visitors dominated the first half with some attractive football.
Eade put a free header over the bar from five yards but atoned with the opening goal after 36 minutes, turning his marker and rifling a low shot into the corner of the net.
Four minutes before half-time a defender's horrible miskick close to the goal line fell to King and he fired in from a narrow angle.
Red Star had offered little in attack, their one attempt on goal bringing an excellent double save from Chris Ogden, but they stepped up their tempo after the interval.
Both sides hit the bar and there was controversy midway through the half when Eade was sent clear and appeared to be brought down in the area by the keeper with an empty net beckoning. However, the referee gave a free kick outside and did not show a card of any colour to the keeper, who was the last defender.
Ogden produced a brilliant reflex save from point blank range but could not prevent Adam Lumb knocking in the rebound four minutes from time.
Brighouse Old Boys moved out of the relegation zone with a 3-2 win at Salem in a basement battle.
Salem started the better and took the lead after 10 minutes when Jason Kirby couldn't hold onto a vicious free kick and Dan Manly forced the ball home.
Brighouse settled with central midfielder Adam Williams, strong running Pete Kuleczko and James Coates to the fore.
Adam Bedford's shot was brilliantly saved by Salem 'keeper Steven Hawksworth and Kuleczko and Bedford went close before Steve Ashford's bullet header crashed against the bar.
Bedford equalised after a surging run and pinpoint cross from Wayne Cummings and as half time approached Brighouse deservedly took the lead, good work by Kuleczko enabling Ashford to score.
Sub Phil Coombes slid the ball home from close range to make it 3-1 and Hawksworth made a handful of superb saves, the woodwork helping to keep Salem in it.
Salem grabbed a lifeline with five minutes left when Lou Kenny fired home but Old Boys held on.