Everest Three Passes Weather: Month-by-Month Guide

Why the Window Is Narrower Than for Everest Base Camp

Everest Base Camp is walkable in winter by well-equipped trekkers because it follows one valley with lodges the whole way. The Three Passes circuit is different. It depends on three high crossings, and each one is a snow-loading, wind-exposed feature with no shelter on top and no lodge for six to nine hours. That changes the calculation in two ways.

First, a pass can be closed while the valleys are perfectly fine. A 30 cm overnight snowfall is a nuisance in Dingboche and a hard stop on Cho La. Second, the passes are sequential, so a closure does not simply cost you a day — it can strand you on the wrong side of the circuit with a two or three-day detour to get back on plan.

The practical result is that most trekkers should treat October to early November and April to early May as the real seasons, with late September, late March and mid-May as viable shoulders for people with flexible dates and pass experience.

Temperatures Along the Route

Typical daytime and overnight ranges during the main trekking seasons. Winter figures run roughly 8 to 12 °C colder overnight at every altitude.

Air temperature is only half the story on the crossings. All three passes funnel wind, and a -8 °C morning with a 40 km/h wind on Kongma La feels closer to -20 °C on exposed skin. A windproof shell, a proper hood and goggles or wraparound glasses matter more here than an extra fleece layer.

Month-by-Month Breakdown

January and February — the passes are effectively shut

The valleys are cold and often clear, and Everest Base Camp is done in winter by experienced parties. The passes are another matter: deep, wind-loaded snow, short days, and most Chukhung, Dzongla and Thagnak lodges closed for the season. Attempting the full circuit now is a mountaineering undertaking rather than a trek, and the lack of open lodges at the pass staging points is usually the decisive problem.

March — opening up, snow still deep on the crossings

The valleys warm quickly and lodges reopen through the month. The passes are still holding winter snow in early March and become progressively more reliable through the second half. Late March is a genuine option for trekkers happy to carry microspikes and accept that one crossing may need a rest day. Trails are quiet, which is a real attraction.

April — the best of spring

The strongest spring month. Days are warm at valley altitudes, the passes are usually clear of fresh snow, and stable high pressure gives long runs of good weather. Visibility is excellent early in the month and starts hazing toward the end as pre-monsoon moisture builds. Lodges are busy but not October-busy. If you want spring, aim for the first three weeks of April.

May — warm, hazier, then unsettled

The first half of May still works well and is the warmest comfortable period on the passes. From mid-May, afternoon cloud build-up and pre-monsoon thunderstorms become routine, and mountain views become unreliable. Late May is not a sensible time to commit to three crossings.

June to mid-September — monsoon

Not a realistic season for this trek. Cloud sits in the valleys for days, the passes are wet and greasy, the Khumbu and Ngozumpa glacier crossings become slick, and views are largely absent. Lukla flights are cancelled routinely, which on a 20-day itinerary can consume your whole contingency before you have started. Some lodges above 4,500 m close.

Late September — the season opens

The monsoon usually withdraws in the last week of September, and the first clear days that follow are often spectacular because the air has been washed clean. The risk is timing: an extended monsoon can leave the passes snowed in and the trails wet into early October. A good choice for flexible travellers, a gamble for those with fixed flights.

October — peak season and the best conditions

The single best month. Stable weather, exceptional visibility, comfortable valley temperatures and passes that are usually clear and well tracked. The trade-off is traffic: the Lukla-to-Dingboche section is genuinely crowded in mid-October and lodge beds at Gorak Shep and Gokyo need booking ahead. On this circuit the crowding largely disappears after Chukhung, which is one of the trek's quiet pleasures.

November — cold, clear and quieter

Visibility stays excellent and trekker numbers drop noticeably after the first week. Nights get seriously cold at Lobuche and Gorak Shep, and the passes start seeing the first significant snowfalls in the second half of the month. Early November is arguably the best balance of conditions and space on the whole calendar. By late November you need to be prepared for a pass to be closed.

December — the door closes

Early December can still deliver clear, bitterly cold days, and a few strong parties do the circuit. By mid-December snow accumulation and lodge closures at the pass staging points make the full loop impractical for most trekkers. Everest Base Camp remains a reasonable winter objective; the Three Passes does not.

Pass Closure Risk and How to Plan Around It

Nobody officially closes these passes. There is no barrier and no announcement — the trails simply become unsafe, guides decline to cross, and the boot-pack disappears. Understanding how each pass behaves helps you build a realistic plan.

• Cho La closes most often. The glacier section near the top is where fresh snow hides crevasses and ice, so guides are conservative here. After significant snowfall, expect a wait of one to three days for a track to be re-established by other parties.
• Kongma La is the wind problem. Less prone to closure by snow depth, more prone to being genuinely dangerous in high wind because the crossing is long and utterly exposed.
• Renjo La is the most forgiving and usually the last to close, though the steep Gokyo-side staircase is unpleasant when iced.

Three planning habits make a closure survivable rather than trip-ending:

• Build two spare days minimum beyond your operator's stated itinerary, on top of the one or two you should already be holding for Lukla flights.
• Know your skip options. Dropping Renjo La and descending the Gokyo valley to Namche is a clean two-day exit. Dropping Cho La means returning from Dzongla to Pheriche. Neither ruins the trek.
• Ask about conditions at every lodge. Trekkers coming the other way crossed the pass yesterday. That is better information than any forecast you can get in Nepal.

See the best time to trek guide for how these seasons interact with crowding and cost, and the route map for where the bail-out points sit.

Getting a Usable Forecast on the Trail

Generic weather apps are close to useless in the Khumbu because they interpolate from valley stations and cannot resolve what happens on a 5,500 m col. What actually works:

• Mountain-specific forecast models such as Meteoblue or Mountain-Forecast, which let you pick an altitude band. Load them over lodge wi-fi in Namche, Dingboche or Gokyo — Everest Link cards work at most lodges on the route.
• Your guide's network. Guides message each other constantly about conditions. A guide who has just heard from a colleague who crossed Cho La this morning is your single best source.
• The pattern, not the day. In October and April the Khumbu usually follows a rhythm of clear mornings and cloud building after midday. Plan pass crossings for pre-dawn starts and you sidestep most afternoon weather entirely.
• Sagarmatha National Park and lodge noticeboards occasionally post conditions, though these are informal and not always current.

The one rule worth holding to: on a pass day, if visibility is poor at the staging lodge at 5 am, wait. Losing a morning is cheap. Being caught navigating a glaciated col in a whiteout is not.