Weather in Kathmandu 🇳🇵
Monthly weather averages & travel planning
September
Avg Temp
25°C
Rain Days
28 days
Sun Hours
8 hrs
Humidity
70%
Asia › 🇳🇵 Nepal › Kathmandu
Updated: March 2026
Is September a Good Time to Visit Kathmandu?
4/10
Fair
September is a fair time to visit Kathmandu (4/10). With 8 daily sunshine hours and only 28 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 10th sunniest of the year in Kathmandu. September suits travellers visiting for indoor culture, food, and architecture rather than outdoor activities. Pack accordingly for 28 potential rain days. August offers a similar profile at lower hotel rates if dates are flexible. Watch out for prolonged rain stretches: with 28 wet days, a fully outdoor itinerary is risky. Build in museum days and covered market visits as contingency. Planning tips: most accommodation categories have availability, and last-minute deals are common. The quieter streets and shorter queues can make this a genuinely enjoyable time to visit for the right type of traveller. Budget-conscious visitors will find the best value of the year in this period.
vs August:25°C avg high
Visiting Kathmandu in September means warm daytime temperatures peaking at 25°C. Factor in 28 potential rainy days and 70% average humidity when planning your daily activities.
25°C
77°F
Avg High
19°C
66°F
Avg Low
28 days
349 mm total
Rain Days
8h
per day avg
Sunshine
70%
Moderate
Humidity
Temperature in Kathmandu in September
The 6°C day-night temperature range is typical for continental climates: a light jacket in the morning that you shed by midday and need again after sunset. Humidity averages 70%, which is comfortable for most visitors. On warmer days, lighter fabrics help with the mild stickiness in the afternoon. UV index averages 6 this month, classed as moderate. Sunscreen is a sensible precaution for extended outdoor time, particularly at midday. Winds are calm at an average 6 km/h, so wind-chill is not a factor in planning your clothing. In Fahrenheit: 77°F average high, 66°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Temperature Trends
High
Low
Rainfall (mm)
0-20 mm21-50 mm51-100 mm100+ mm
What to Wear in Kathmandu in September
Morning19°CBefore the day warms up
Afternoon25°CPeak daytime temperature
Evening22°CAfter sunset cools down
Packing for Kathmandu in September means dressing for 25°C days and 19°C evenings. A light cotton tee with a casual overshirt works well at 25°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 19°C, a modest 6°C drop that a light cardigan or denim jacket covers. Comfortable walking trainers are the versatile choice for both outdoor sightseeing and indoor venues. With 28 rain days expected, a compact travel umbrella is worth the bag space. A waterproof jacket is better than an umbrella if you plan full-day outdoor routes. For temple and religious site visits, carry a lightweight scarf or sarong to cover shoulders and knees, required at most major sites across the region.
Local tip: Temple and religious site visits require covered shoulders and knees in most of Kathmandu's heritage areas. A lightweight scarf or sarong weighs almost nothing and solves the problem instantly.
Events in Kathmandu in September
September has no major festivals or public holidays in Kathmandu, which is one of its practical advantages for independent travellers. Attractions run at lower capacity than during peak event periods, queues are shorter, and accommodation is easier to find without needing to book many months in advance. Local restaurants, markets, and transport operate at a relaxed pace, making this an ideal time for visitors who prefer a more authentic, unhurried experience of everyday city life rather than large crowds drawn in by a single major headline event.
What to Pack for Kathmandu in September
Based on 25°C average highs and 28 rainy days
- Light layers for morning and evening
- Breathable T-shirts and comfortable trousers
- UV-protective sunglasses
- Compact folding umbrella
- Waterproof outer layer or packable rain jacket
- Quick-dry clothing that recovers fast after a shower
- SPF 30+ sunscreen
- Comfortable walking shoes (a second pair lets the first air out overnight)
- Universal travel adapter
- Small day pack for city exploration
- Reusable water bottle
Best Activities in Kathmandu in September
- Explore outdoor markets and street food stallsMid-morning (10am-12pm)At 25°C, the temperature is ideal for extended walking without overheating
- Guided walking tour of the historic centreMorning or late afternoonComfortable temperatures allow several hours on foot without fatigue
- Visit rooftop viewpoints and observation decksGolden hour (1 hour before sunset)Warm clear evenings provide exceptional visibility for panoramic photography
- Day trip to the surrounding countryside or coastFull day (depart by 8am)September is reliably dry enough for rural day trips without weather risk
- Spend a morning in the national or city art museumOpens at 10am; arrive earlyWith 28 rain days expected, having a full-day indoor plan is practical insurance
- Cooking class focused on regional cuisineHalf-day sessions run 10am-1pm or 3-6pmIndoor activity that fills a rainy half-day with genuine cultural content
- Visit covered historical sites: cathedral, palace, or bazaarAny time; most crowded middayRoofed monuments and covered markets provide exploration without weather exposure
- Visit the main botanical garden or city park at seasonal peakYear-round; best light in morningSeptember brings distinct seasonal changes to public green spaces worth exploring
- Try the seasonal farmer's market for local produce and street foodSaturday morning markets typically 8am-1pmSeptember seasonal produce is at peak availability, offering dishes not found at other times of year
Why is Kathmandu warm in September?
Kathmandu's September heat is driven by the Asian summer monsoon system, as the low-pressure cell that forms over the heated landmass draws warm, humid air from the oceans. The result is temperatures averaging 25°C with high moisture in the air. Overnight temperatures remain elevated at 19°C, as clouds and humidity prevent the earth from radiating heat away after sunset. Climate data: Open-Meteo ERA5 (1991–2020).
Sunshine Hours
The average number of hours per day with direct sunlight. Calculated from satellite measurements. Days with more than 7 hours of sunshine are ideal for outdoor activities. Under 3 hours means overcast conditions dominate.
UV Index
A scale from 0-11+ measuring ultraviolet radiation intensity. UV 0-2: Minimal risk. UV 3-5: Moderate, wear sunscreen. UV 6-7: High, hat and SPF 30+ essential. UV 8-10: Very High, limit midday exposure. UV 11+: Extreme, seek shade between 10am-4pm.
Rain Days
A rain day is counted when precipitation exceeds 0.1mm. This threshold captures even light drizzle. Unlike total rainfall in mm, rain days tells you how often you might need an umbrella, which is useful for planning outdoor activities.
Humidity
Relative humidity as a percentage. Below 40%: Dry, skin and throat may feel parched. 40-60%: Comfortable, ideal for most people. 60-80%: Sticky, light breathable fabrics recommended. Above 80%: Muggy, heat feels more intense; quick-dry clothing is essential.
Frequently Asked Questions
Kathmandu in September
In September, Kathmandu experiences average highs of 25°C (77°F) and lows of 19°C (66°F). Expect around 28 rainy days and 8 hours of sunshine per day, with humidity averaging 70%. The 6°C gap between daytime and overnight temperatures is worth planning around: light layers work for most visitors during the day, but an overshirt or cardigan handles the cooler evenings. UV index averages 6, so sun protection is advisable on clear days.
Kathmandu typically sees 28 rainy days in September, with total precipitation of around 349mm. This is a notably wet period. A waterproof jacket or compact umbrella is essential, and it is worth building indoor alternatives into your daily itinerary for the inevitable rainy stretches. For context, the driest month in Kathmandu typically sees 4-6 fewer rain days than September.
Pack light layers, a light jacket for evenings, comfortable walking shoes, and sunscreen for Kathmandu in September. Daytime temperatures of 25°C are pleasant, but the evening drop to 19°C means a jacket is essential if you plan to be out after dark. With 28 rainy days, bring a compact umbrella or waterproof jacket for unexpected showers. Comfortable walking shoes are a priority given the amount of ground most visitors cover.
September is a reasonable time to visit Kathmandu. Expect 28 rainy days, so pack a light rain layer for flexibility. Average temperatures of 25°C make outdoor exploration comfortable during the dry periods. With 8 daily sunshine hours, there are reliable windows of good weather to plan outdoor activities around, even if the month is not the driest on the calendar.
The average high temperature in Kathmandu in September is 25°C (77°F), and the average low is 19°C (66°F). The mean daily temperature is approximately 22°C (72°F). The day-to-night range of 6°C is moderate, meaning a single light jacket covers most situations. These are 30-year climate normals based on the 1991 to 2020 reference period; individual years will vary, particularly in transitional months like spring and autumn.
The best month to visit Kathmandu is generally March. March offers the most sunshine at 11 hours per day and only 10 rainy days. Average temperatures reach 22°C, making it comfortable for sightseeing, outdoor dining, and exploring the city. If your travel dates are flexible, planning your trip around March gives you the best chance of dry, bright weather.
September is shoulder or low season in Kathmandu, meaning fewer tourists and generally lower prices than peak months. With 8 sunshine hours and 28 rainy days, the weather is less of a draw for mass tourism. This is an advantage for travellers who prefer a quieter, more relaxed experience with shorter queues and easier accommodation availability.
In September, Kathmandu suits a range of activities thanks to mild temperatures around 25°C. With frequent rain, indoor activities and covered attractions are a smart choice. Top options include exploring historic neighbourhoods, visiting museums and galleries, local food markets, and day trips to surrounding areas. With 8 hours of sunshine, parks and waterfront walks are particularly enjoyable.
September ranks 10th sunniest of the year in Kathmandu, with an average 8 daily sunshine hours. The driest months are December, January, and November. May is the hottest month (26°C avg high); January is the coolest (16°C). From here, temperatures fall 2°C into October. Compared to last month (August: 25°C high, 31 rain days), September is similarly warm and drier. September is one of the least sunny months, but that often means lower prices and fewer fellow tourists.
Year-Round Climate
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 16°C | 7°C | 6 | 10h | View |
| February | 18°C | 8°C | 8 | 10h | View |
| March | 22°C | 11°C | 10 | 11h | View |
| April | 25°C | 14°C | 13 | 12h | View |
| May | 26°C | 17°C | 22 | 12h | View |
| June | 26°C | 19°C | 27 | 9h | View |
| July | 25°C | 20°C | 31 | 6h | View |
| August | 25°C | 20°C | 31 | 7h | View |
| September | 25°C | 19°C | 28 | 8h | View |
| October | 23°C | 15°C | 15 | 10h | View |
| November | 20°C | 12°C | 6 | 10h | View |
| December | 17°C | 8°C | 3 | 10h | View |
January
6 rain days, 10h sun
16°7°
February
8 rain days, 10h sun
18°8°
March
10 rain days, 11h sun
22°11°
April
13 rain days, 12h sun
25°14°
May
22 rain days, 12h sun
26°17°
June
27 rain days, 9h sun
26°19°
July
31 rain days, 6h sun
25°20°
August
31 rain days, 7h sun
25°20°
September
28 rain days, 8h sun
25°19°
October
15 rain days, 10h sun
23°15°
November
6 rain days, 10h sun
20°12°
December
3 rain days, 10h sun
17°8°
Other Months in Kathmandu
Plan Your Trip to Kathmandu
Data Sources for Kathmandu
Climate normals represent 30-year averages (1991-2020). Individual years may vary.