Parkes stormed to a 26-nil lead in the first 40 minutes of Sunday's game, in bitterly cold conditions at Spooner Oval.

"We got blown away a bit," coach Cameron Greenhalgh rued on Monday.

"We just didn't come out ready to play.

"Parkes had momentum and we couldn't break it."

The Spacemen came out strong in the second-half too, crossing for another try almost immediately to give themselves a 30-nil lead over the home side in the final regular round of the Group 11 season.

But that try was enough to make the Magpies click into gear for the final 30 minutes of the game.

Suddenly they were all over it, and within four points of the Spacemen just a minute out from the final whistle.

"We made it look easy," Greenhalgh said.

But an intercept in the dying stages of the game saw Parkes cross the line just one more time for a solid scoreline of 40-30.

The first grade coach still believes Forbes finished the better side, and hopes they can pick up where they left off when the two sides meet again in the semi-final next Sunday.

"We need to do what we didn't do yesterday," Greenhalgh said.

"Next weekend is a whole new ball game."

At this early stage the conditions are looking kinder for the faithful fans of a twin town derby, who turned out even in Sunday's icy conditions even if many did stay in their cars and sound their horns to signal their support.

On the whole it was a great day for the Magpies.

Forbes dominated the early games: the league tag and 18s played in wet and windy conditions.

The first game of the day was the league tag and possibly in the toughest conditions, the ball slippery in the rain.

A conversion was the only difference in the first half, the Magpies led 6-4 at the break.

The Spacecats crossed to make it an 8-6 lead just a few minutes into the second half but the Magpies stuck it out to celebrate a 12-8 win in the rain at the final whistle.

That result also sets up a rematch against Parkes, at Parkes, next weekend.

Forbes finished second on the ladder, four points behind Dubbo CYMS and one point ahead of the Parkes Spacecats.

Juniors took the field next and put on what Greenhalgh described as one of their best performances all season.

Two quick tries gave them a 12-nil lead and set the tone within the first 10 minutes of the game.

Parkes had plenty of ball possession, but the young Magpies didn't give an inch.

Forbes led 16-nil at half time and had extended that lead to 28-nil at full time, still playing in quite wet and windy conditions.

The final-round win sees the Magpies retain top rung on the juniors ladder, one point ahead of Dubbo CYMS.

The young Magpies hit the road to Wellington next weekend to take on the Cowboys, who have finished the regular season in third place on the ladder.

Reserve grade was a low-scoring contest and a tight game, the scoreline reflecting that at 8-6.

Next weekend the reserve grade heads to Wellington to take on CYMS.