In short
- October to November offers the most stable weather and clear skies.
- March to May provides warmer temperatures and blooming rhododendrons.
- Winter months bring severe cold and a high risk of pass closures.
In this article
Choosing the right season for the Annapurna Circuit is crucial for your safety and comfort. While the trail is technically open year-round, crossing the high-altitude Thorong La Pass requires clear weather and manageable snow conditions. Understanding the distinct trekking seasons will help you plan a successful circuit.
Why is autumn the best time to trek Annapurna Circuit?
October and November provide the most stable weather, clear skies, and manageable temperatures for high-altitude trekking.
During autumn, the monsoon rains have cleared, leaving crisp air and excellent visibility of the Annapurna Massif. The trails are dry, making steep ascents and scree slopes, like those near Tilicho Lake, much safer to navigate.
Daytime temperatures at lower elevations are comfortable for hiking. However, temperatures drop sharply at night, so you will still need a sleeping bag rated to -15°C (5°F) for teahouses above 4,000 meters.
What is the spring trekking season like?
March to May is the second-best window, offering warmer weather and blooming rhododendron forests at lower elevations.
Spring brings warmer days, which helps melt winter snow on Thorong La. The lower Marsyangdi valley comes alive with colors from rhododendrons and alpine flora. This season is slightly less crowded than October.
However, spring can sometimes have hazy skies due to dust or pre-monsoon cloud buildup in the afternoons. It is still a very safe and popular time to cross the pass.
Is it safe to cross Thorong La Pass in winter?
Winter trekking (December to February) is dangerous due to extreme cold and frequent pass closures from heavy snowfall.
While the lower sections of the circuit are accessible, the high-altitude areas become treacherous. Thorong La Pass often becomes impassable due to deep snow and severe winds. Tilicho Lake (4,919m) also freezes over entirely.
If you attempt the circuit in winter, you must have extra days built into your itinerary to wait out storms, and many teahouses in higher villages like Thorong Phedi may be closed.
How does weather affect the Tilicho Lake detour?
The landslide trail to Tilicho Base Camp is highly vulnerable to heavy rain or snow, making it best attempted in autumn.
The detour to Tilicho Lake features a notorious landslide-prone trail. During the summer monsoon or heavy winter snows, this path becomes extremely risky. Autumn provides the driest, most stable conditions for this side trip.
Even in peak season, you must start early from Tilicho Base Camp to reach the lake before fierce, freezing mid-morning winds begin.
Can you trek the Annapurna Circuit during the monsoon?
Summer (June to August) brings heavy rains to the lower valleys, though upper regions like Manang are partially shielded.
The lower sections of the trek, including Besisahar to Chame, get hit hard by monsoon rains. This causes muddy trails, leeches, and potential landslides. The road up the Marsyangdi valley frequently washes out.
Once you reach the upper Manang valley, the Annapurna range blocks much of the rain, creating a rain shadow. However, getting there is difficult, and views are often obscured by low clouds.
| Season | Months | Pros | Cons |
|---|---|---|---|
| Autumn | Oct - Nov | Clear skies, stable weather | Busiest trails, cold nights |
| Spring | Mar - May | Warmer days, flowers | Afternoon haze possible |
| Winter | Dec - Feb | Quiet trails | Extreme cold, pass closed |
| Monsoon | Jun - Aug | Lush valleys, fewer crowds | Mud, rain, obscured views |
How to prepare for changing weather conditions
Pack versatile layers, including a windproof outer shell and a heavy down jacket, regardless of the season.
Even in October or April, weather at 5,000 meters is unpredictable. You must carry high-quality UV-protection sunglasses to prevent snow blindness at Thorong La and Tilicho Lake. Gear Essentials
Micro-spikes are strongly recommended, as icy patches can linger on the trails to Tilicho Lake and the pass well into the spring and autumn trekking windows.
Questions travellers ask
Do I need a guide for the Annapurna Circuit in 2026?
Yes. Nepal's 2023 rule calls for foreign trekkers to use a licensed guide through a registered agency; enforcement on this route varies, so confirm before you go.
How long does the Annapurna Circuit and Tilicho Lake trek take?
The typical duration is 12 to 16 days to complete the circuit with the Tilicho Lake detour, depending on your pace and transport use.
How cold is Thorong La Pass?
At 5,416 meters, temperatures are consistently below freezing, especially before sunrise. High winds make it feel much colder, requiring serious winter gear.
