Weather in Chamonix-Mont-Blanc in January
France · 20-year averages, January
The month to avoid. Of the twelve, January is the one to avoid. Highs sit at 1.8 °C and the day is short; this is an indoors-with-excursions month, not an outdoors-all-day one.
January ranks 12 of 12 — near the bottom of Chamonix-Mont-Blanc's year. September is the month that works, and the swing between the two is 59 points, which is a different holiday rather than a slightly better one.
Rain on 13 days, 4 of them heavy. Enough to need a plan B, not enough to need a plan around it. Layers, and a genuinely waterproof outer — at 1.8 °C the difference between a good day and a miserable one is entirely down to what you are wearing.
What the averages hide
Averages flatten a month, and this one hides a few things: 29 nights drop below freezing, so anything left outside stays frozen. Across the twenty years measured, the hottest January day reached 10.2 °C and the coldest night fell to -21.1 °C, and the wettest single day dropped 53 mm — roughly 50% of the month's rain in one day.
January is moderately variable: 37 mm in the driest year against 306 mm in the wettest, around an average of 107 mm. Roughly two Januarys in three land near that average, and the third does something else entirely.
Wind is light at 3.6 km/h, so the temperature on the page is close to the temperature on your skin, and humidity runs at 86%, which at 1.8 °C means damp rather than muggy — the kind of cold that gets into a coat and stays there.
How January sits in the year
Temperatures hold steady either side: 3.3 °C in December, 1.8 here, 2.2 in February. Nothing about the timing within the month matters much.
Daylight in January
January sits at the dark end of Chamonix-Mont-Blanc's year — 9 hours of daylight against 15.7 at midsummer, gaining 0.9 hours across the month. Sightseeing days are genuinely shorter, and an itinerary built for summer will not fit.
An inland climate
With no coast nearby, the year swings a fair way — 28.9 °C between the warmest afternoons and the coldest nights, wider than any coastal city at this latitude would manage. At 1060 m the air is thin enough to matter — sun that burns faster than the temperature suggests, and nights that cool off quickly.
How busy it gets
Off season. The genuine off season: cheapest by a distance, with the caveat that some tours and restaurants close entirely.
Crowd levels are estimated from climate desirability and school-holiday calendars, not from visitor numbers.
January in Chamonix-Mont-Blanc versus nearby
If Chamonix-Mont-Blanc is one option among several, the nearby comparison is worth making. Annecy is a better bet in January — 3.5 °C warmer, the same number of rain days. Zermatt is close enough to be a coin toss — 3.1 °C cooler, 2 days less rain.
So: January is a compromise. September is 59 points better and is what Chamonix-Mont-Blanc is actually like at its best — worth moving the trip for if that is possible, and worth adjusting expectations for if it is not.
Every month in Chamonix-Mont-Blanc
| Month | High °C | Low °C | Rain days | Rain mm | Humidity % | Daylight h | Score |
|---|---|---|---|---|---|---|---|
| January | 1.8 | -6.5 | 13 | 107 | 86 | 9 | 14 |
| February | 2.2 | -6.7 | 11 | 76 | 87 | 10.3 | 20 |
| March | 5.2 | -2.7 | 14 | 94 | 86 | 11.8 | 22 |
| April | 11.5 | 2.4 | 13 | 74 | 80 | 13.5 | 49 |
| May | 16.2 | 6.3 | 18 | 117 | 79 | 14.9 | 53 |
| June | 20.4 | 10.8 | 16 | 105 | 77 | 15.7 | 70 |
| July | 22.2 | 12.3 | 16 | 103 | 75 | 15.4 | 70 |
| August | 22.1 | 12 | 15 | 105 | 74 | 14.2 | 72 |
| September | 18.8 | 8.6 | 13 | 76 | 77 | 12.6 | 73 |
| October | 14.9 | 5.1 | 12 | 86 | 78 | 11 | 60 |
| November | 8 | 0.1 | 13 | 94 | 84 | 9.5 | 37 |
| December | 3.3 | -4.5 | 14 | 110 | 84 | 8.7 | 15 |
See all twelve months in Chamonix-Mont-Blanc, or where else to go in January.
Planning the rest of the trip
- Flight time to Chamonix-Mont-Blanc how long you are actually in the air
- Chamonix-Mont-Blanc time zone and the difference from home
- Days until your trip count down to the departure date