Nepal's Climate Zones
Nepal's dramatic elevation range — from 60 m in the Terai plains to 8,849 m at Everest's summit — creates five distinct climate zones, each with its own weather patterns, flora, and fauna.
Terai (Sub-tropical)
Hot and humid. Avg. 25–40°C in summer, 15–25°C in winter. Heavy monsoon rainfall. This is where Chitwan National Park is located. Best weather: Nov–March.
Kathmandu Valley (Temperate)
Warm summers, mild winters. Avg. 5–29°C year-round. Monsoon June–September brings humidity and grey skies. Clear, bright weather in Oct–Nov and March–May.
Hills (1,000–3,500m)
Moderate temperatures, pleasant climate. This is where most major trek lower sections fall. Cold winters above 2,000 m. Heavy monsoon rainfall. Best season: October–May.
High Mountains (3,500–5,500m)
Cold year-round with heavy winter snowfall. Temperature ranges from -20°C in winter to 15°C in summer. Trekking best October–November and March–May when snow is manageable.
Arctic Zone (5,500m+)
Permanently snow-covered. Temperatures rarely exceed 0°C. Only experienced mountaineers with technical equipment venture here. Everest summit: -20°C to -35°C average.
Trans-Himalayan (Rain Shadow)
Upper Mustang, Dolpo, and Humla receive minimal monsoon rainfall because the Himalayan wall blocks the rain clouds. Accessible and pleasant even during June–September when other regions are wet.
Kathmandu Weather by Month
| Month | Avg High (°C) | Avg Low (°C) | Rainfall | Conditions |
|---|---|---|---|---|
| January | 18°C / 64°F | 2°C / 36°F | Low | Clear, cold nights, sunny days |
| February | 20°C / 68°F | 4°C / 39°F | Low | Warming, occasional fog mornings |
| March | 25°C / 77°F | 9°C / 48°F | Low–Med | Pleasant, clear, spring blooms |
| April | 29°C / 84°F | 13°C / 55°F | Medium | Warm, some afternoon clouds |
| May | 30°C / 86°F | 17°C / 63°F | Medium | Pre-monsoon heat, occasional storms |
| June | 29°C / 84°F | 19°C / 66°F | Very High | Monsoon begins, heavy rain |
| July | 28°C / 82°F | 20°C / 68°F | Very High | Peak monsoon, daily downpours |
| August | 28°C / 82°F | 20°C / 68°F | Very High | Monsoon continues, lush green |
| September | 27°C / 81°F | 18°C / 64°F | High | Monsoon tapering, clearing skies |
| October | 25°C / 77°F | 12°C / 54°F | Very Low | ⭐ Clear, perfect weather |
| November | 22°C / 72°F | 7°C / 45°F | Very Low | ⭐ Clear, crisp, ideal |
| December | 18°C / 64°F | 3°C / 37°F | Low | Cold mornings, clear afternoons |
Monsoon — What You Need to Know
Nepal's monsoon (June–September) brings 80% of the country's annual rainfall in just four months. While trekking is not recommended in most regions, the monsoon has its own beauty and benefits.
Challenges of Monsoon Travel
Leeches on trekking trails above 1,500 m. Muddy, slippery paths. Low visibility — mountains hidden behind cloud. Flight delays at Lukla and mountain airports. Some mountain roads flooded or landslide-prone.
Benefits of Monsoon Travel
Spectacular waterfalls everywhere. Lush emerald landscapes. 30–50% lower hotel and flight prices. Fewer tourists (Kathmandu's museums and temples are uncrowded). Upper Mustang is in rain shadow — excellent trekking.