The most relevant weather information is from Hans Island near 81 N latitude.
ORIGINAL Post (6/28/2012):
The collapse of the ice-arch in southern Nares Strait began June-27, 2012 with development of a small hairline fracture along the western side of the strait off Ellesmere Island, Canada. The fracture connects an isolated area of open water off Bache Peninsula, Canada at 79 N latitude. The front between land-fast ice in the north and the open water in the south has moved slightly southward. It has also lost a visible larger piece of ice that before anchored the bridge at its western connection to land. This motion will open the hairline fracture more, accelerating the collapse of the ice-arch. The missing support of the ice-arch on its western side will collapse the entire ice-arch and the previously land-fast ice of Nares Strait will stream rapidly to the south, I predict, before this weekend.
Updates (including an animation) will be posted daily at http://muenchow.cms.udel.edu/Nares2012/Kane/.
This collapse happens each year in the summer, though the timing varies from April for weak and July for strong arches. The arch in 2012 lasted longer than the one in 2011. No or only weak ice-arches formed at this site in 2007, 2008, and 2009, e.g., http://muenchow.cms.udel.edu/MODIS/.
EDIT-1: Same imagery, same gridding, but more focus and detail
EDIT-2: The moorings we try to recover this summer are to the north of Kane Basin and to the south where Petermann Fjord enters Nares Strait. This map shows it (also notice how badly the coastline of Greenland is surveyed):