Update, July 3, 2017:
On Friday, June 30, the climbing team made it to within 60 vertical metres of the summit of Mount Logan, but were prevented from reaching the peak by severe white-out conditions. They exercised caution, and retreated to Camp Five, their highest camp on the mountain.
The following day, they descended to Camp Three, again in white-out conditions and 30 kilometre per hour winds at minus 13 degrees Celsius. Sunday saw them safely back at Base Camp, at 2770 metres (9000 feet) elevation. When the weather is right, a ski plane will whisk them back to civilization.
With five other climbers, Rosslander Gerry Heacock is on Mount Logan, heading toward the summit. The crew flew into their base camp on June 15, and since then have been hauling loads to establish their higher camps, acclimatizing, and making upward progress. Located in Kluane National Park in the south-west corner of Yukon Territory, Mount Logan is Canada's highest peak, and the second-highest in North America after Denali. It is also a UNESCO World Heritage Site.
Trevor Greene, one of the climbers, has been posting their route and occasional brief reports on this website, so readers can track those reports:
The climbers started at 9,000 ft (2743 m) elevation, and will be travelling up the King's Trench route for approximately 25 kilometers to the summit elevation of 19,551 feet(5,959 metres), weather permitting. The weather is the most challenging part of any climb here; Heacock's partner, Rachel Selkirk, reports that fewer than half the teams attempting Logan this year have been successful summiting.
Severe storms sweep Mt. Logan at all times of year, and extremely cold temperatures have been recorded on its upper reaches: on May 26, 1991, a temperature of minus 77.5 degrees Celsius was reported -- the coldest reported temperature outside of Antarctica. Heacock's team reported a relatively mild base-camp temperature of minus three Celsius on June 23, with a report of minus 24 at the peak that day.
Mount Logan was first climbed 92 years ago by a team of Canadian, British and American mountaineers. At that time, there were no planes flying climbers in to a base camp; the six intrepid explorers trekked 200 kilometres to establish their base camp from the nearest town ― McCarthy, Alaska. They reached the summit of Logan on June 23, 1925. They were: Albert H. MacCarthy (leader), H.F. Lambart, Allen Carpé, W.W. Foster, Norman H. Read and Andy Taylor. It took them 65 days to trek to the mountain, accomplish their first ascent of the mountain, and return.
Heacock and his companions arguably have an easier trip -- or at least a shorter one. The 1925 crew would have acclimatized to higher elevations more gradually, which has health advantages. But the 1925 crew may have experienced better weather, for at least part of their trip.