Best Time to Hike Half Dome: Cables Season Explained

The best time to hike Half Dome is mid-June or September. The cables are typically up from the Friday before Memorial Day (late May) until the day after Columbus Day (mid-October) — June offers thundering waterfalls and 15-hour days, while September trades them for stable weather and lighter lottery competition.

Timing the Half Dome Trail is really three separate questions: when the cables are up, when the weather cooperates, and when you can actually win a permit. Get all three right and you have one of the world's great hiking days — 23 km, 1,460 m of climbing, and a summit at 2,694 m reached up 120 m of steel cable. Here is how the season breaks down.

When are the Half Dome cables up?

The National Park Service raises the cables onto their stanchions for roughly late May to mid-October — conditions permitting, which is the phrase doing heavy lifting. In big snow years the opening has slipped into June; early-season storms can close the route temporarily any time. Outside cable season the route is not "harder" — it is a technical climb requiring rope skills and is the source of a disproportionate share of the mountain's accidents. If the cables are down, the hike is off. Current status is posted on the NPS Half Dome page.

Month by month: how the season actually feels

Why afternoon thunderstorms set your schedule

Sierra summer convection is punctual: cumulus builds late morning, storms fire early-to-mid afternoon, mostly July and August. The cables are 120 m of steel on exposed granite — exactly where you must not be when lightning arrives, and the rock becomes dangerously slick merely wet. The protocol is fixed: start by 5:30–6:00 from Happy Isles, summit before noon, and turn around without negotiation if cloud towers early. Check the National Weather Service point forecast for Yosemite Valley the evening before; a 30%+ thunderstorm probability is a reason to be descending Sub Dome by 11:00. Run your own pace through the hiking time calculator — at a typical 3.5 km/h average over this terrain, a 6:00 start puts you on the summit around 11:30, which is already cutting it fine in August.

How does timing interact with the permit lottery?

Demand peaks June through August: weekend dates in the March preseason lottery have drawn success rates around 20–30%, while September weekdays can double your odds. If your dates are flexible, target the second half of September — stable weather and the season's friendliest lottery math. The daily lottery (apply two days ahead) also softens noticeably after Labor Day. As of 2026, applications cost $10 plus $10 per person, all through Recreation.gov.

What changes about your kit through the season?

June hikers want a shell for the Mist Trail's spray and 3–4 litres of water capacity for the heat; the ~300 g Zpacks Bagger Ultra 25L carries that with room for summit layers. September and October add a real insulating layer — summit wind chill near 0°C is normal — which is where a 35-litre pack like the Patagonia Ascensionist 35L stops being overkill. Fast parties moving at run-hike pace do the route with a Salomon ADV Skin 20 vest and grippy approach-style shoes, which matter more than anything else on the cables. If you're comparing Sierra objectives for the same trip window, our guides to the best time for Mount Whitney and the best season for Angels Landing use the same month-by-month framework — and the Mount Whitney Trail itself runs a near-identical season, with its lottery in February rather than March.

The one-line answer for five common situations

• First attempt, want the classic experience → second half of June: full waterfalls, dry cables, 15-hour days.
• Hate crowds more than you love waterfalls → mid-September weekday: half the cable traffic, double the lottery odds.
• Locked into July–August dates → any day with a clean overnight forecast, started at 5:30 sharp; skip the daily lottery on storm-forecast days, since others will too and the next day's pool improves.
• Photographer chasing conditions → first week of June for Nevada Fall at peak, or early October for low-angle light and empty summit shots.
• Couldn't get any permit → late September Clouds Rest, which needs no lottery and arguably out-views the dome itself.

Frequently Asked Questions

What time should you start hiking Half Dome?

Start between 5:00 and 6:00 from Happy Isles. The 23 km round trip takes 10–14 hours, and an early start gets you up the cables before the midday crowds, off the summit before the afternoon thunderstorm window, and back before dark — sunset leaves no margin for a 19:00 finisher who started at 9:00.

Can you hike Half Dome when the cables are down?

Not as a hike. When the cables are lowered (roughly mid-October to late May), the final 120 m is a technical climb on smooth 45-degree granite, attempted only with rope, harness and experience. Permits are not required when cables are down, which misleads some hikers — several serious accidents happen there each off-season.

How cold is the Half Dome summit?

Typically 10–15°C colder than Yosemite Valley, plus wind. On a 30°C July valley day the 2,694 m summit may sit around 15–18°C with strong gusts; in late September expect single digits with wind chill near freezing. Carry a windproof layer year-round and an insulating layer from September.

Is June or September better for Half Dome?

June if you want Yosemite at maximum drama — Vernal and Nevada Falls at full power and 15 hours of daylight — at the cost of tougher lottery odds and possible early-season snow patches. September if you want stable weather, cooler climbing and roughly double the permit success rate. Both beat July–August's heat and storm cycle.