"There were high winds yesterday which have died down a bit but it's still very blustery on the hill and the areas we want to look at have had a lot of fresh snowfall blown in so they are very unstable and we wouldn't like to put people in there until there is a bit of settlement.
"It's always a worry when you're putting people in to these areas. It's quite scary and very hard work in these conditions."
It is thought the couple had been camping behind the Charles Inglis Clark memorial hut on the north side of the mountain.
It is hoped rescue teams will be able to resume their search at the mountain later today.
Mr Stevenson added: “We'll just have to wait and see - it's the snow conditions that will determine what we can do and where we can go.
"We'll keep reviewing it and as and when we'll try and send people out.
“As time goes on it's very difficult, the weather conditions have been really bad and no-one has heard from them or seen them is a worry. You always have hope but as time goes on that diminishes quite rapidly.”
Anyone who was climbing or walking in the Ben Nevis area over the weekend and saw the couple is being urged to contact police on 101.
