Everest Base Camp Weather: Temperature Is Set by Height, Not by the Date

Everest Base Camp sits at 5,364 m (17,598 ft) on the moraine of a glacier, and it is below freezing there at night in every month of the year. That is as precise as we are willing to be, because we do not hold a temperature for it that anybody outside this company has checked.

There is a second reason the question is hard to answer well. You do not sleep at base camp. Nobody does. You walk out to it in the middle of the day, stand on the rock, take the photograph, and walk back to Gorak Shep, the last village with beds, at a height our sources still disagree about. The cold that matters to you is therefore not the cold at base camp. It is the cold in an unheated room at Gorak Shep in the middle of the night, and the cold on Kala Patthar, 5,545 m (18,192 ft), before dawn the day after.

The night figure our own corpus holds for base camp is an operator claim that no weather service has confirmed, so it stays off this page. The section below on why there is no table here explains exactly what is wrong with it, and we would rather show you that than hand you a number that looks authoritative and is not.

What you can act on is simpler than a number anyway. Your warmth on this trek is decided by three things you control: a sleeping bag rated for a genuinely cold night, a down jacket, and a windproof layer over the top. The lodge does not keep you warm. Your bag does. The Everest Base Camp packing list covers each item and what you can rent in Kathmandu rather than buy.

The trail climbs about 2,504 m between the airstrip at Lukla and base camp, and it does it on foot, one village at a time. Air gets colder as you go up. That single fact moves the temperature on this trek far more than the date on your ticket does.

Start with what this means for the forecast you are probably looking at. Kathmandu is a long way south of the Khumbu and far lower, in a warm valley of its own. A forecast for Kathmandu describes Kathmandu. It tells you what to wear for the taxi to the airport and nothing whatever about the trail. Two people on the Everest Base Camp trek on the same afternoon, one eating outside at Namche Bazaar, 3,440 m (11,286 ft), and one crossing the moraine above Lobuche village, 4,910 m (16,109 ft), are standing in different climates.

The route walks up through those climates in order. Forest, then thinning forest, then the tree line, then rock and moving ice. Nothing shelters you after Dingboche, 4,410 m (14,469 ft). You can watch the change happen out of the window of a lodge, and it is the best guide to what the next night will feel like that anyone can give you.

The month still matters. It decides how often the sky is clear, how much snow is lying, how busy the lodges are and how reliably the flight into Lukla runs. It is simply not the main thing deciding whether you are cold. Which month to pick is a whole decision of its own and it has its own page: the best time to trek to Everest Base Camp.

We hold day and night temperature ranges for every village on this route, and we are not printing them, because we cannot tell you who measured them. They come from our own parent company, they have never been checked against a weather service, and a second table on the same company website contradicts them.

Here is the contradiction, without the numbers, because publishing either set would be the mistake this section is about. One table gives day and night ranges for the villages on the way to base camp.2 A second table on a sister article covers several of those same villages and gives different ranges for them.3 Same company, same valley, same villages, two answers. At least one of them is wrong and we have no way of knowing which.

There is a third table, arranged by month, and it has a worse problem. It never says what height its figures apply to. On a trek that climbs about 2,504 m, a temperature with no height attached is not a fact about anything. Our store marks those rows with a hollow circle for exactly that reason, and the one place they are allowed to appear is next to a description of what is wrong with them. So here is one row, as an exhibit.

What would change this. One weather service that publishes measurements for this valley, states the height of its instruments, and says how long it has been recording. That is a single document and we have not got it yet. When we do, this page gets a real table, every figure on it carries that source, and we will write the date we added it at the foot of the page. Until then you get the shape of the thing and an honest blank where the numbers go. That is worth more than a confident table assembled from two tables that disagree.

The weather in this valley runs to a daily pattern far more reliably than it runs to a monthly one. Mornings are usually the clearest part of the day. Cloud builds up the valley through the middle of it. The sky often clears again after dark, and a clear night is a cold night.

That pattern is the reason every day on this trek starts early. You walk in the clear air, you get the mountains before they go behind cloud, and you are in a lodge with tea in your hands by the time the afternoon turns. It is also why the Kala Patthar climb happens before dawn, in the dark, in the coldest hour of the trip. The view is only there in that window.

The cost of that rhythm is real and worth stating. You get up in the dark, you are cold until the sun reaches you, and you are eating breakfast at an hour that feels wrong. Nobody enjoys the first stretch of it. The alternative is walking the hardest part of the day into afternoon wind and looking at grey cloud where Everest was, so the early start wins.

The other thing to watch is the sun, not the clock. Once the sun goes behind a ridge the temperature drops fast, and it goes behind the ridge long before it sets. This is why lodges light the dining room stove in the late afternoon rather than at nightfall. Put your jacket on when the light leaves the valley, not when you start shivering.

No tea house bedroom on this trek has heating. Not at Namche Bazaar, not at Dingboche, and not at Gorak Shep, which is the highest and the coldest night you will spend. The stove in the dining room is the only heat in the building, it is lit in the late afternoon, and it is out before you go to bed.

A room at Gorak Shep at night is, in practice, the outside temperature with the wind taken off it. The walls are boards. There is a mattress, a pillow and one blanket. People wake up in the small hours, put on the down jacket they were wearing at dinner, and get back into the bag in it. That is normal here and it is what the regulars do.

Two practical habits make that night better. Fill a water bottle with hot water from the kitchen before bed and put it in the bottom of your sleeping bag, which keeps your feet warm for hours and gives you unfrozen water in the morning. And keep tomorrow’s socks, your camera battery and your phone inside the bag with you, because cold flattens a battery overnight and a cold camera on Kala Patthar is a camera that does not work.

What the lodges are actually like, room by room and village by village, is on the page about the tea houses on the Everest Base Camp trek. Sleeping badly at that height is common on its own, but telling the difference between a bad night and a symptom is the most important judgment on this trek, and it belongs to the altitude sickness and acclimatization page. Tell your guide in the morning how you slept. Every time.

Wind decides whether a cold day is manageable or miserable, and it does not appear on the temperature line of any forecast. A still, sunny day high on this route can be pleasant. The same day with wind on it will drive you into a lodge by the middle of the afternoon.

The valley tends to be calmest early and to get up as the day warms. Combined with the cloud pattern, that is the second reason for an early start. The stretches where you will notice it most are the open ground above Dingboche where nothing grows tall enough to break it, the moraine ridges up to Lobuche village, the walk out along the Khumbu Glacier to base camp, and the exposed ridge of Kala Patthar before sunrise.

The gear answer is not more insulation, it is a shell. A windproof outer layer over your down jacket is worth more on those stretches than a thicker jacket, because it stops the air stripping the warmth off you. Cover the back of your neck and your face. Wear gloves you can still work a zip and a camera in, so you are not pulling them off every time you need your hands.

Snow is possible on the upper half of this route at any time of year, and it is most likely in winter and around the edges of the monsoon. A light fall changes very little. A serious one changes your whole plan, and it usually does it by stopping the flight rather than by blocking the path.

On the trail, fresh snow does two things. It hides the route across the moraine, where the path is already hard to read because it runs over loose rock rather than soil. And it melts in the sun and freezes again overnight, which turns the steep, polished sections above Namche Bazaar and the descents into ice in the early morning. Neither is dangerous with a guide who knows the ground and a pair of boots with real grip. Both are slow, and slow at altitude costs you more than it does at home.

The flight is the fragile part. Lukla is the piece of this trip that weather stops most often, and cloud and wind at the airstrip are what stop it rather than snow on the trail. That is worth planning for with spare days at the end, not with optimism. What actually happens when it is canceled, and what the alternatives cost you in time, is on the page about the Kathmandu to Lukla flight.

The monsoon on this route mostly means cloud rather than constant rain. It runs through the middle of the year, from June to early September. It is warm, it is wet lower down, and the mountains you came for are usually behind a grey wall by the middle of the morning.

A typical day is not a washout. It often starts clear, fills in from below as the valley heats up, and rains in bursts rather than all day. The rain is heaviest on the lower half of the walk, below Namche Bazaar, where the forest is thick and the trail turns to mud. Leeches live in that forest and they come out in the wet. Higher up, above the tree line, you get cloud and cold rather than downpours, and the valley sometimes clears late in the afternoon.

The real cost is not comfort, it is the flight and the view. Lukla cancels far more often in these months, so a trip planned tight to a return flight is a trip planned badly. And a trek to base camp where you never once see Everest is a possible outcome, which most people booking it have not pictured.

We run treks in these months for people who ask for them, and we tell them exactly what they are buying. It is quiet, it is green, the lodges have space, and the risk sits with the flight and the sky. Whether that trade is right for you is a decision, not a weather fact, and the decision is on the page about when to trek to Everest Base Camp.

A temperature you would find mild at home is not mild at this height, and the gap between the number and the feeling is wide enough to catch people out. Four things do it, and none of them shows up on a forecast.

The first is the sun and the shade. The air is thin and dry, so sunlight arrives with real force and shade takes it away instantly. In the middle of the day you can be too warm in a shirt on a south facing slope, walk round the corner into the shadow of the ridge, and be cold inside a minute. Dress for the shade with wind on it, not for the sun.

The second is wind, which the section above covers, and the third is that you are wet. You sweat on the climbs even when it is cold, and a damp base layer under a down jacket at a rest stop is the fastest way to get chilled on this trek. Take a layer off before the climb rather than after it.

The fourth is you. Most people eat less than they need at altitude and drink less than they should, and both make you feel the cold more than the same person would at home. Food is fuel for staying warm as much as for walking. The reason your appetite goes in the first place, and what to do about it, is on the altitude sickness page, which is the one page on this site to read before you come.

We get a forecast the same way you will, on a phone in a lodge, and we trust the near end of it and treat the far end of the week as a guess. Mountain weather in a valley this deep is local, and a forecast covering a region this size cannot see into it.

There is wifi and mobile data in most villages on this route, and both get worse and more expensive as you climb. What that actually looks like, carrier by carrier, is on the tea house page, along with an honest note about how settled that information is.

One trap is worth naming. A forecast you find by searching for Everest is very often one of two things that are no use to you. It is either a summit forecast, made for climbing teams, describing wind and temperature far above your head at the top of the mountain, or it is a Kathmandu forecast wearing the word Everest. Neither describes the village you are standing in. If you are going to check something, check the nearest named settlement and read it as a rough steer.

In practice the decisions that matter are made in the morning, by your guide, looking at the valley. What time you leave, whether the Kala Patthar climb is worth getting up for, whether to push on or stop early. That judgment is the part of this you are actually hiring, and it is described on the page about how we run the trek.

And the honest limit. Nobody can tell you in the spring what the sky will be doing on your base camp morning in the autumn. You book for the season, you build spare days around the flight, and you accept that the mountain decides the rest.

Every number above is listed here with the body that publishes it and the date we last read it. If a figure has changed since, write to us and we will correct the page and say that we did.