Guide · altitude and temperature
How cold is it at the top?
The single most common surprise on a Swiss mountain excursion is the temperature. People leave a valley town in shorts, ride up two or three kilometres, and step out into much colder air. Elevation gives a useful first estimate, but not a forecast: here is a rule of thumb for the excursions reached from our three base towns, and why actual temperatures can differ.
The rule of thumb: 6.5 °C per 1,000 metres
A standard-atmosphere estimate assumes cooling of 6.5 °C for every 1,000 m. This is the standard-atmosphere lapse rate. The actual environmental lapse rate varies with place and time, so use this for orientation, then check the summit forecast.
The biggest climb in this catalogue is Jungfraujoch, at 2,886 m above the base town you set off from, which works out at roughly 19 °C of drop. A hypothetical 25 °C in that town gives about 6 °C at the top under this assumption, before considering how wind affects comfort.
Convert it yourself in one step: take the valley temperature, and subtract 6.5 for every kilometre of climb. That is the whole method, and it is the reason a summer excursion needs a coat.
The drop, mountain by mountain
Grouped by the town you set off from, because the climb is what matters, not the summit height on its own. Zermatt is already a mountain village at 1,608 m, so its excursions climb far less than their altitudes suggest — the single fact that most surprises people comparing Zermatt with Interlaken.
From Interlaken, 568 m
| Excursion | Summit | Climb | Estimated drop | Example: 25 °C in town |
|---|---|---|---|---|
| Jungfraujoch | 3,454 m | 2,886 m | −19 °C | 6 °C |
| Schilthorn | 2,970 m | 2,402 m | −16 °C | 9 °C |
| Grindelwald First | 2,166 m | 1,598 m | −10 °C | 15 °C |
| Schynige Platte | 1,967 m | 1,399 m | −9 °C | 16 °C |
| Harder Kulm | 1,322 m | 754 m | −5 °C | 20 °C |
From Lucerne, 436 m
| Excursion | Summit | Climb | Estimated drop | Example: 25 °C in town |
|---|---|---|---|---|
| Mount Titlis | 3,020 m | 2,584 m | −17 °C | 8 °C |
| Mount Pilatus | 2,132 m | 1,696 m | −11 °C | 14 °C |
| Stanserhorn | 1,898 m | 1,462 m | −10 °C | 15 °C |
| Mount Rigi | 1,798 m | 1,362 m | −9 °C | 16 °C |
From Zermatt, 1,608 m
| Excursion | Summit | Climb | Estimated drop | Example: 25 °C in town |
|---|---|---|---|---|
| Matterhorn Glacier Paradise | 3,883 m | 2,275 m | −15 °C | 10 °C |
| Gornergrat | 3,089 m | 1,481 m | −10 °C | 15 °C |
Glacier 3000 is left out of the tables on purpose: it is reached from no single base town in this catalogue, so there is no honest valley figure to measure the climb from. Its summit is 2,946 m, which puts it in the same band as the high excursions above.
Every figure here is arithmetic on two verified elevations, not a forecast. For what it is actually doing on the mountain today, each name links to its own page.
Why the temperature drop varies
A sunny summit is not automatically colder than a cloudy one.The actual valley-to-summit difference depends on the air mass, mixing, surface heating and temperature inversions. Cloud cover alone does not determine it.
Adiabatic lapse rates describe a different question: how a parcel of air changes temperature as it rises or sinks. They are not bounds on the temperature difference between two places. The table uses the 6.5 °C standard assumption only; the forecast on each mountain's page is the better guide for your day.
When the summit is warmer than the town
The usual temperature decrease can reverse during an inversion. Colder air can sit beneath warmer air, with fog or low cloud trapped below. A summit above that layer may be warmer and sunnier than the valley, but an inversion does not guarantee fog, sunshine or a warmer temperature at every mountain height.
It is why the greyest-looking days from Lucerne are sometimes the best days on Rigi or Stanserhorn when its seasonal transport is running. Both can clear a shallow layer and have transport included with the Swiss Travel Pass. Our cloud diagram uses forecast inputs; it does not measure cloud-top height or guarantee sunshine. Check the summit forecast rather than the valley alone.
Wind, and the temperature you actually feel
A thermometer reading is not what your skin reports. Wind strips away the thin film of air your body has warmed, so the same air feels progressively colder as it moves faster — and exposed summit terraces are windy places by construction. The gap between measured and felt temperature widens with wind speed and matters most exactly where the measured figure is already near zero.
Every attraction page here shows summit wind beside summit temperature, and the hourly strip carries both through the day, so the windier hours are visible before you choose a departure.
What to take
Dress for the summit, not the station. That single sentence covers most of it, and the tables above show why elevation matters. For the actual trip, check the summit temperature and wind forecast rather than packing from the valley temperature alone.
A warm mid-layer and something windproof cover the ordinary case even in high summer on the highest excursions. Sunglasses matter more than people expect, because snow and ice at altitude reflect a great deal of light back at you.
Comfort, not safety. This site rates sightseeing excursions reached by cable car and mountain railway — it does not give hiking, route or mountaineering advice, and nothing here should be read as preparation for leaving the marked visitor areas.
Common questions
- How much colder is it at the top of a Swiss mountain?
- About 6.5 °C colder for every 1,000 m of elevation gain is a standard-atmosphere rule of thumb, not a forecast. From Interlaken at 568 m to Jungfraujoch at 3,454 m, applying it to 25 °C in town gives about 6 °C at the top. Actual conditions can differ substantially; check the summit forecast.
- Is a sunny summit always colder than a cloudy one?
- No. The actual temperature difference between a valley and summit depends on the air mass, mixing, surface heating and inversions. The dry and moist adiabatic rates describe a parcel of air rising or sinking, not a sunny-day or cloudy-day temperature rule for two places. Use the summit forecast, not sky colour, to judge the temperature.
- Can a Swiss summit be warmer than the valley below it?
- Yes. During an inversion, colder air can sit beneath warmer air, sometimes with fog or low cloud trapped below. A summit above that layer may be warmer and sunnier than the valley. It is a possibility, not a guarantee at every summit height; use the summit forecast.
- What should I wear on a Swiss mountain excursion in summer?
- Plan for the summit rather than the town you leave from. A mild summer valley day can still mean a cold summit, and the standard temperature-drop estimate is not a forecast. Check summit temperature and wind; a warm layer and a windproof layer can be useful even when town feels warm.
- Is it below freezing at the top of Matterhorn Glacier Paradise in summer?
- It can be. At 3,883 m it is about 2,275 m above Zermatt, giving roughly 15 °C of drop under the standard rule of thumb. That estimate alone cannot tell you whether it will freeze on a particular summer day; check the summit forecast.
- Does wind make a mountain summit feel colder?
- Substantially. Wind strips away the thin layer of air your body warms, so the temperature you feel can be several degrees below the one a thermometer reads — the gap widens as wind speed rises. Every attraction page on this site shows summit wind alongside temperature for exactly this reason.
What this page is not
Saying so plainly is the point rather than a disclaimer. Everything above is arithmetic on two verified elevations plus published physics. It contains:
- No forecast. Not one temperature here is a prediction for a particular mountain on a particular day. The tables give drops, which are subtraction; the current model forecast for each mountain is on its own page, refreshed at summit elevation every 30 minutes when ingestion is healthy.
- No claim of precision. Drops are rounded to whole degrees because the actual temperature gradient varies with place and time. The standard atmosphere cannot tell you a particular day's temperature to a decimal place.
- No altitude-health advice. How thin air affects a particular person is a medical question, and not one we are in any position to answer.
The other half of the decision
Knowing it will be cold is useful. Knowing whether you will be able to see anything is the decision — every Swiss mountain we track, ranked right now, with a PEAK, MAYBE or SKIP verdict from live summit conditions. If cost is the other half of your question, the Swiss Travel Pass coverage guide works out which of these are free, which are half price, and which are neither.