Guide to Mt. Everest Region Weather and Temperature

Ask what the temperature is "on Everest" and the honest answer is: which part? The gap between Everest Base Camp and the summit isn't a matter of degrees — it's a different physical world, separated by 3,500 vertical meters and roughly 45°C of average temperature difference. Understanding that gap, and the science behind why Everest's weather behaves the way it does, is genuinely useful whether you're planning a trek to Base Camp or just curious about what makes this mountain's climate so extreme.

This guide covers the physics and the numbers: summit versus Base Camp temperatures, why banner clouds form over Everest's summit, the weather station network now monitoring conditions at unprecedented altitude, and how climate change is measurably reshaping the region.

If you're planning your own trek and want the practical month-by-month trekking breakdown, see our dedicated Everest Base Camp Weather by Month guide — this page focuses on the science of Everest's weather rather than trip planning. For help choosing when to go, see Best Time to Trek Everest Base Camp.

If you haven't finalized your itinerary yet, our Everest Base Camp Trek page has the current route and departure dates.

Trek the Everest Base Camp Trek

This classic trek takes you through the heart of the Khumbu region, past vibrant Sherpa villages, ancient monasteries, and towering Himalayan peaks.

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Quick Answer

How cold does it get on Mount Everest?

At the summit (8,849m), temperatures can plunge to around -60°C (-76°F) or lower in winter, with average conditions even in the relatively milder pre-monsoon climbing season rarely climbing above roughly -19°C. At Everest Base Camp (5,364m), conditions are far milder by comparison but still genuinely cold — typically ranging from about -15°C to -30°C depending on season, with a December–January average around -17°C (1.4°F). The difference comes down to altitude, wind chill, and how little warmth thin, high-altitude air actually retains even under strong sun.

Temperatures at the Summit vs. Base Camp

The scale of this difference is worth sitting with for a moment: Everest's summit sits at 8,849m, while Base Camp — already a serious high-altitude destination in its own right at 5,364m — is roughly 3,500m lower. That's enough elevation difference on its own to explain a huge swing in temperature, even before wind chill and exposure are factored in.

At the summit: temperatures can drop to approximately -60°C (-76°F) or lower during the depths of winter (mid-December through late January), when the mountain averages around -37°C (-35°F). This is why winter ascents of Everest are vanishingly rare compared to the spring climbing season — the physical margin for survival narrows dramatically.

At Base Camp: conditions are dramatically milder in comparison but still demand serious cold-weather preparation. Typical temperatures range from about -15°C to -30°C depending on time of year, with a December–January average of roughly -17°C (1.4°F).

The spring shift: by April and May, conditions on the mountain change enough that climbers at Camp 3 and below sometimes trek in little more than a t-shirt during the warmest part of the day — even though nights remain genuinely cold. This dramatic seasonal swing is a core reason spring is the primary Everest climbing season.

What actually drives these extremes:

• Altitude — air pressure drops as you climb, and with it, the air's ability to hold and transfer heat. As a rough rule, temperature falls roughly 1°C for every 150m of elevation gained.
• Wind chill — strong, near-constant winds at the summit dramatically amplify how cold conditions actually feel and how quickly the body loses heat, often mattering more than the raw air temperature itself.
• Thin-air solar radiation — sunlight at extreme altitude is intensely strong (a real sunburn risk) but the thin atmosphere holds almost none of that warmth, so intense sun and dangerous cold coexist in a way that surprises people who haven't experienced it.

For the full month-by-month trekking temperature breakdown at Base Camp and along the trail, see our Weather by Month guide rather than repeating that full data set here.

Trekking Seasons: A Brief Summary

Everest region trekking follows four broad seasons, each with a different weather character:

This is intentionally a summary, not the full picture — for detailed monthly temperatures, snow conditions, crowd levels, and Lukla flight reliability by season, the Weather by Month guide covers all twelve months in depth, and Best Time to Trek Everest Base Camp helps you match a season to your specific priorities.

Himalayan Precipitation Patterns

The Everest Base Camp region experiences a surprisingly dry climate overall, with roughly 80% of annual precipitation falling during the monsoon (June through September) and comparatively little the rest of the year. ⚙️ Approximate annual totals cited in various sources put Base Camp at roughly 18 inches of precipitation annually, against a considerably wetter Lukla at approximately 70 inches — treat these exact figures as indicative rather than precise, but the underlying pattern they describe is real and well-documented.

Why such a stark difference over a relatively short distance: the moisture driving Nepal's monsoon originates over the Indian Ocean and travels north. As that moisture-laden air hits the southern slopes of the Himalayas, it dumps the bulk of its rainfall there — meaning by the time weather systems reach the Everest Base Camp region, much of that moisture has already been wrung out. This is a classic rain shadow effect, and it's a genuine part of why Base Camp itself stays comparatively dry even during peak monsoon, while lower approach villages see considerably more rainfall.

The high altitude and cold temperatures of the Everest region further limit how much moisture the air can hold in the first place, and the near-constant wind at higher elevations sweeps away what moisture does arrive before it can accumulate as significant precipitation.

Winter snowstorms, while uncommon, do occur — powerful mid-latitude storm systems occasionally cross the region and can deposit over a meter of snow at Base Camp with relatively little warning. This is a real, if infrequent, risk factor for winter trekkers and is exactly why windproof clothing, gaiters, and flexible planning matter if you're trekking in December through February. For more on cold-weather trekking safety generally, see our altitude sickness guide, which covers how cold and dehydration interact with altitude risk.

Trek the Everest Base Camp Trek

This classic trek takes you through the heart of the Khumbu region, past vibrant Sherpa villages, ancient monasteries, and towering Himalayan peaks.

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Banner Clouds on Everest

One of Everest's most distinctive visual features has nothing to do with storms at all: the mountain's pyramidal shape, combined with the powerful winds that constantly sweep its summit, produces a rare and striking cloud formation known as a banner cloud.

Banner clouds typically stream out from the downwind side of the summit against an otherwise clear blue sky — a dramatic, flag-like plume that's become one of the mountain's most photographed features. They form because strong wind flowing around the peak creates a temporary low-pressure zone on the leeward side, which draws moisture upward and condenses it into this distinctive, elongated cloud shape.

Banner clouds aren't unique to Everest — the Matterhorn in the Swiss Alps produces similar formations — but Everest's combination of extreme altitude, isolated peak shape, and position relative to prevailing winds makes it one of the most reliable places on Earth to observe them. Earlier theories attributed the phenomenon primarily to Everest's position within the jet stream; more recent research points to the combination of wind strength and the mountain's specific shape and orientation as the more significant factors.

Weather Stations Near Everest

Accurate, real-time weather data is genuinely a safety-critical resource on Everest — both for trekkers planning around Lukla flight reliability and for climbers timing a summit push around narrow weather windows. Two very different projects have shaped how that data gets collected.

The Pyramid International Laboratory/Observatory (Lobuche)

Located near Lobuche at 5,050m in the Khumbu Valley, the Pyramid is an Italian-Nepali scientific research station inaugurated in October 1990 — considerably earlier than the "since 2006" figure sometimes still circulating online. Jointly managed by the Ev-K2-CNR Committee and Nepal's Academy of Science and Technology, it has hosted over 500 scientific missions across meteorology, glaciology, seismology, and high-altitude human physiology since it opened, and was recognized by the World Meteorological Organization as a reference atmospheric monitoring point in 2014.

It's a short, popular detour from the main Base Camp trail — about 20 minutes from Lobuche, reached by crossing a glacier into a narrow side valley — and many trekkers add it as a worthwhile extra stop for both the scientific interest and the unique valley views.

The Highest Weather Stations on Earth (2019–present)

The more significant development in Everest weather science happened far higher on the mountain. In May 2019, a National Geographic and Rolex-backed expedition — working with Appalachian State University, King's College London, and Nepal's Department of Hydrology and Meteorology — installed a network of five automatic weather stations on and around Everest, culminating in one at the Balcony, 8,430m up the Southeast Ridge. At the time, it was the first terrestrial weather station ever placed above 8,000m, and it remains among the highest points any permanent scientific instrument has been installed on Earth.

The Balcony station stopped transmitting in January 2020 after roughly seven months, likely due to the extreme winter winds it was built to study. In 2022, the same team returned and installed a redesigned station roughly 380m higher, at a site called Bishop's Rock, specifically engineered to better withstand the conditions that destroyed its predecessor. A second high-altitude station at the South Col (7,945m) has also operated as part of the same network.

Why go to this much effort and expense: these stations sit within reach of the subtropical jet stream, a powerful high-altitude wind band that's historically been difficult to study directly. Data from this network feeds into both climate research — with real implications for the roughly 1.6 billion people downstream who depend on Himalayan freshwater — and, practically, into the increasingly sophisticated weather forecasting that professional expedition teams now rely on to time summit attempts.

So while Lobuche's Pyramid remains a genuine and historically important piece of Everest's scientific story, it's this considerably higher, more recent network that now represents the actual frontier of Everest weather monitoring.

Trek the Everest Base Camp Trek

This classic trek takes you through the heart of the Khumbu region, past vibrant Sherpa villages, ancient monasteries, and towering Himalayan peaks.

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Everest and Climate Change

Like most of the world's high-altitude glaciated regions, Everest is measurably changing as the climate warms.

The glaciers that have shaped the Khumbu landscape for millennia are retreating at a pace that concerns researchers studying the region — a trend that carries consequences well beyond the mountain itself, affecting downstream water security for communities that depend on glacial meltwater for agriculture and daily life.

For climbers and their Sherpa guides, melting ice and increasingly unstable slopes translate directly into elevated avalanche and crevasse risk, while less predictable weather patterns make already-narrow summit windows harder to plan around.

The impact reaches well beyond expedition teams. Sherpa communities living in the Khumbu face disrupted agricultural cycles and, in some areas, genuine water scarcity as traditional patterns shift — a slower-moving but no less serious consequence of the same warming trend affecting the ice above their villages.

Everest's climate is, in this sense, a fairly direct proxy for the health of the broader planet — which is part of why the scientific monitoring described above, however difficult and expensive to maintain at these altitudes, matters well beyond satisfying climbers' curiosity about the forecast.

Trek the Everest Base Camp Trek

This classic trek takes you through the heart of the Khumbu region, past vibrant Sherpa villages, ancient monasteries, and towering Himalayan peaks.

View Trip

Frequently Asked Questions

How cold is it at the summit of Mount Everest? Temperatures can drop to around -60°C (-76°F) or lower in winter, with a typical December–January average near -37°C (-35°F).

How cold is Everest Base Camp? Typically -15°C to -30°C depending on season, with a December–January average of roughly -17°C (1.4°F) — much milder than the summit, but still genuinely cold.

What is the closest weather station to Mount Everest's summit? As of 2022, a station at Bishop's Rock (roughly 8,400m+), part of a National Geographic and Rolex-backed network, holds that distinction — considerably closer to the summit than the historic Pyramid Observatory near Lobuche at 5,050m.

Why does Everest have banner clouds? Strong wind flowing around the mountain's pyramidal summit creates a low-pressure zone on the downwind side, drawing moisture upward into a distinctive, flag-like cloud visible against clear sky.

What causes the extreme temperature difference between Base Camp and the summit? Primarily altitude — roughly 1°C colder for every 150m of elevation gained — compounded by dramatically stronger wind chill and thinner air at the summit that holds almost no warmth even under intense sun.

Is Everest Base Camp drier than the surrounding region? Yes, considerably — a rain shadow effect means moisture-laden monsoon air loses most of its precipitation on the Himalayas' southern slopes before reaching the Base Camp area, which sits well below wetter lower villages like Lukla in annual rainfall.

When is the best weather for climbing Everest's summit? Primarily spring (April–May), when a relatively stable weather window opens between the depths of winter cold and the onset of monsoon.

Is the Pyramid Observatory still operating? It remains a real, visitable research station and a popular trekking detour near Lobuche, though its active scientific monitoring has reportedly been reduced since Italian government funding cuts around 2015. Confirm its current operational status directly if this matters for your planning.

How is climate change affecting Everest specifically? Measurably — retreating glaciers, increasing avalanche and crevasse risk from unstable slopes, and less predictable weather windows for both climbers and the Sherpa communities who depend on the region's water and traditional agricultural patterns.

Do I need to worry about extreme summit temperatures on a Base Camp trek? No — trekkers visiting Base Camp itself experience nothing close to summit conditions. Base Camp's cold is serious and requires real preparation, but it's a different order of magnitude from the -60°C extremes climbers face far higher on the mountain.

Conclusion

Everest's weather is genuinely one of the most extreme and scientifically significant climate systems on Earth — a mountain cold enough at its summit to make winter ascents nearly unthinkable, yet hosting a Base Camp that thousands of ordinary trekkers reach safely every season with the right preparation. The science behind that gap — altitude, wind chill, thin-air physics, and now a network of weather stations reaching higher than anywhere else on the planet — is part of what makes this region as scientifically fascinating as it is physically demanding.

If you're planning your own trek to experience this climate firsthand, our Everest Base Camp Trek page has current departure dates, and our Weather by Month guide will help you plan around the season that fits what you're looking for.

Trek the Everest Base Camp Trek

This classic trek takes you through the heart of the Khumbu region, past vibrant Sherpa villages, ancient monasteries, and towering Himalayan peaks.

View Trip