A severe blizzard stopped an expedition attempting to put the first American woman atop Mt. Everest, a spokesman for the climbers said. Lee Hicks, Seattle spokesman for the American Everest North Face Expedition, said two climbers, Mimi Stone of Seattle and Michael Graber of Mammoth Lakes, Calif., climbed to within 1,000 feet of the summit of 29,028-foot Everest. Stone is among five women in the 15-member expedition led by Scott Fischer of Seattle. Hicks said adispatch from Katmandu, Nepal, said all the climbers are safe andwill arrive in Katmandu by Thursday or Friday.