Mont Lachat
📍 Rhone-Alpes , Departement de la Haute-Savoie · Nearest city: Les Houches (2 km)
58 XC score / 100 · takeoff at 2053 m · 📍 View on map
Coordinates and external links
45.87140, 6.79389Forecast next days
Updated: 2026-04-21 01:20 UTC · Source: Open-Meteo · Thermal window 10:00–18:00 local time
Flyable day, decent conditions, cloud base ~1113 m, wind 14 km/h.
base ~1113m · wind 14 km/hFlyable day, decent conditions, cloud base ~1675 m, wind 16 km/h.
base ~1675m · wind 16 km/hVery favorable day for XC, cloud base ~1406 m, wind 12 km/h.
base ~1406m · wind 12 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 19h
- Very stable day (CAPE<50, LI>2) — no thermals
- High cloud suck (91/100) — base below freezing with CU
| 08 30 ☁️⚠️ | 09 30 ☁️⚠️ | 10 30 ☁️⚠️ | 11 30 ☁️⚠️ | 12 50 ☁️⚠️ | 13 50 ☁️⚠️ | 14 45 ☁️⚠️ | 15 45 ☁️⚠️ 🏔️ | 16 40 ☁️⚠️ 🏔️ | 17 40 ☁️⚠️ | 18 50 ☁️⚠️ | 19 55 | 20 55 |
Peak 19h: CAPE 0 J/kg · LI 2.8 · BL top 735 m · w* 0.0 m/s · cloud base 2590 m · 0°C at 2870 m · Pro score 58/100
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: 19:00 (peak of the day)
Surface T: 6.9°C · Td: 2.6°C
LCL (cloud base): 537 m
BL top: 735 m
0°C level: 2870 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) | 7 | Medium |
| Avg thermal probability | 0.86 | Based on thousands of aggregated IGC flights |
| Solar orientation | 0.38 | Slope faces south in northern hemisphere |
| Own flight history | 0.00 | Thermals detected in platform IGC tracks |
Nearby sites
Saint Gervais - Les Chavants (5) · Mont Vorassay (57) · Saint-Gervais-les-Bains - La charme (48) · Domes de Miages (62) · Les houches - Gravière (5) · Les houches - aiguillette - l'aiguillette (5)