JMT from Yosemite in late June: big water, snow, and the Donohue question

Late June sits right on the edge of the JMT season. The permit data and most planning guides call July 1 through September 30 the reliable window, and the reason shows up in the first 36 miles: Donohue Pass tops out at 11,066 feet, and in a normal snow year it still carries snow patches in the last week of June. Creek crossings run at their loudest and most dangerous from June into early July. None of that makes a late-June start wrong. It makes it a different trip, one for hikers who are comfortable on snow and willing to move slower. Permits first, because they control everything. Yosemite issues only 45 southbound Donohue-eligible permits per day: 15 from Happy Isles and 30 from Lyell Canyon. The 2026 lottery closed March 15 with results out around March 20, and Happy Isles odds run near 10 percent. By late June the lottery is long over, so the paths in are cancellations returning to Recreation.gov and whatever first-come permits the wilderness centers release. Cancellations for late-June dates tend to appear as other hikers look at the snowpack numbers and bail, which quietly makes this window one of the better times to pick up a dropped permit. The Yosemite section itself covers roughly 36 miles from Happy Isles at 4,035 feet to Donohue Pass. The climb past Vernal and Nevada Falls is at maximum volume in June, which means constant spray on the Mist Trail side and slick granite steps. Little Yosemite Valley at mile 4.7 is the first legal camp, and Donohue-eligible permits from Happy Isles often require camping beyond it. Cathedral Lakes at mile 17 sit at 9,288 feet and typically still have snow around the shorelines in late June. Lyell Canyon's 8 flat miles along the Lyell Fork are usually walkable but wet, with the river braiding across the meadow. Water strategy in this window is the opposite of a September trip: the problem is too much, not too little. Every drainage is running. Budget extra time for the Lyell Fork area and for anything unbridged, cross early in the morning when flows are lowest, and unbuckle your hip belt at every crossing. Itinerary-wise, a late-June start usually means three to four days to Donohue rather than the two strong hikers manage in August. Tuolumne Meadows at mile 22.5 is the first resupply, though its services open on their own schedule early in the season. Check that the store and grill are actually operating before you count on them. Common mistakes in this window: - Treating the mileage plan from a July guidebook as valid. Snow travel above 10,000 feet cuts your pace roughly in half. - Skipping traction. Microspikes and an ice axe are standard equipment for Donohue in June, and the permit data lists both for pre-July starts. - Forgetting the bear canister rule. It is required for the entire trail, and rangers at Happy Isles check. - Ignoring the campfire limit. Fires are prohibited above 9,600 feet in Yosemite, which covers most of the good camps past Cathedral Lakes. — Compiled by the PermitSnag team from agency info, ranger updates, and public trip logs.