Joon Chung, Soren Hansen and Matthew King share second place at 3-under-par 141. Jason Dawes, Mark Foster and overnight co-leader Bradley Dredge are one stroke further back at minus-2.
Players battled tough conditions Friday as temperatures slid towards the freezing point and winds gusted throughout the day.
Dodd, who has played on the European Tour since 1995 and is still looking for his first win, began the day one stroke off the overnight lead. He opened with three straight pars before a birdie at the fourth.
The Welshman kept rolling with a birdie at the eighth and came right back to birdie No. 9 to get to minus-7. Dodd however stumbled to a bogey at the 10th.
Dodd bounced back with a birdie at the par-4 15th. He tripped to another bogey at the 17th, but parred the last for a three-stroke overnight lead.
'I've never played in a tournament in conditions like this,' said Dodd. 'I'm just pleased with a 70. We're halfway through the tournament and there are a lot of good players out there. At least I won't be off at 6:15 a.m. tomorrow.'
Chung posted two birdies and a bogey over his first nine holes. He carded back-to-back birdies from the 11th to take the lead at 6 under. He stumbled down the stretch with bogeys at 14, 16 and 17 to drop back into second place.
Hansen got off to a hot start with birdies at 10 and 13 to get to 4 under. He faltered to a bogey at the 17th though. The Dane parred five straight holes around the turn, before tripping to a double bogey at the par-4 fifth.
He responded with a birdie at six, but dropped another stroke at seven. Hansen closed with birdies at eight and nine to share second place.
King opened his round with six consecutive pars. However, he bogeyed two of his next three holes to drop back to minus-2. The Englishman got those strokes back with birdies at 13 and 15. He slipped to another bogey at the 16th before parring the final two holes to share second place.
Thomas Bjorn, Marc Cayeux, Barry Lane, Jonathan Lomas and Simon Yates share eighth place at 1-under-par 143. Gregory Hanrahan, Amandeep Johl, Edward Michaels, Chawalit Plaphol and Chris Williams are one stroke further back at even par.
Uhno Park, who shared the first-round lead with Dredge, tumbled all the way into a tie for 33rd after a second-round of 8-over 80.
The cut line fell at 7-over-par 151 with 72 players advancing to the weekend.