Mont Blanc
📍 Rhone-Alpes , Departement de la Haute-Savoie · Nearest city: Les Houches (8 km)
56 XC score / 100 · takeoff at 4536 m · 📍 View on map
Coordinates and external links
45.83330, 6.86410Forecast next days
Updated: 2026-04-21 01:24 UTC · Source: Open-Meteo · Thermal window 10:00–18:00 local time
Marginal conditions, cloud base ~952 m, strong wind (29 km/h).
base ~952m · wind 29 km/hMarginal conditions, cloud base ~1440 m, strong wind (30 km/h).
base ~1440m · wind 30 km/hVery favorable day for XC, cloud base ~1156 m, wind 6 km/h.
base ~1156m · wind 6 km/hComposite flyability score (CAPE + LI + wind + precip + low clouds). Cross-check with local pilots before flying.
Detailed hourly weather
2026-04-21❌ Not recommended · peak 55 at 14h
- Very stable day (CAPE<50, LI>2) — no thermals
- High cloud suck (96/100) — base below freezing with CU
| 08 30 ☁️⚠️ | 09 30 ☁️⚠️ | 10 30 ☁️⚠️ | 11 30 ☁️⚠️ | 12 50 ☁️⚠️ | 13 50 ☁️⚠️ | 14 55 ☁️⚠️ | 15 55 ☁️⚠️ | 16 40 ☁️⚠️ | 17 50 ☁️⚠️ | 18 50 ☁️⚠️ | 19 55 ☁️⚠️ | 20 55 ☁️⚠️ |
Peak 14h: CAPE 0 J/kg · LI 3.4 · BL top 1505 m · w* 0.0 m/s · cloud base 5323 m · 0°C at 2650 m · Pro score 62/100 · sun 36° over slope
Hourly flyability (0–100). ⛈️ = storm risk · ☁️⚠️ = cloud suck · 🏔️ = active ridge lift. CAPE = convective energy, LI = stability, BL top = thermal ceiling, w* = estimated dry thermal velocity. Source: Open-Meteo (ECMWF/GFS/ICON blend model).
Estimated vertical profile (Sounding)
Reference time: 14:00 (peak of the day)
Surface T: -9.3°C · Td: -15.6°C
LCL (cloud base): 787 m
BL top: 1505 m
0°C level: 2650 m
Approximate profile from surface variables + synoptic levels. Red lines = temperature, dashed blue = dew point. Orange bands = detected inversions.
🌬 Daily wind (next days)
Daily summary (10m wind). Full hour × altitude chart is being added progressively.
Takeoff orientations
Green = good orientation · Yellow = possible · Gray = not suitable
Why this site has thermal potential
| Factor | Value | Interpretation |
|---|---|---|
| Hotspot density (5 km) | 6 | Medium |
| Avg thermal probability | 0.89 | Based on thousands of aggregated IGC flights |
| Solar orientation | 0.15 | Slope faces south in northern hemisphere |
| Own flight history | 0.00 | Thermals detected in platform IGC tracks |
Takeoff description
The very top of the mountain. The ridge is oriented East-West, take off is possible on the North side or on the south side. After take off from the south side, it is possible to join the Chamonix valley by flying over the 'arète de bosses'.
Rules and notes
July-August: restricted area flight see website https://federation.ffvl.fr/actu/r-glementation-vol-libre-dans-massif-mont-blanc
Pilot comments
the true take off altitude is 4810m. the highest take off in Europe
Nearby sites
Aiguille du Midi -S / N (61) · Plan de l'Aiguille (Chamonix) (50) · Domes de Miages (62) · Chamonix - le savoy (5) · Les houches - Gravière (5) · Atterrissage FFVL Bois du Bouchet (5)