Monthly weather averages & travel planning

Asia › 🇨🇳 China › Shanghai
Updated: March 2026
September is a good time to visit Shanghai (6/10). With 9 daily sunshine hours and only 11 rain days, this month delivers genuinely reliable outdoor conditions, ranking it 4th sunniest of the year in Shanghai. Culture-focused travellers and those who prefer lighter crowds will find September a practical choice, with prices running lower than peak July without sacrificing all the good weather. October offers a similar profile at lower hotel rates if dates are flexible. The main practical note: Shanghai's popular sites are busiest between 10am and 3pm regardless of season. Arriving at opening time or after 4pm makes a significant difference to the experience. Planning tips: accommodation is generally available without long lead times, and flight prices are typically lower than peak season. Flexible travellers will find the best deals by booking 2-4 weeks ahead. Mid-week arrivals consistently unlock lower hotel rates than weekend check-ins.
Based on 30-year climate normals (1991 to 2020), September in Shanghai averages 27°C by day and 21°C overnight, a range that places it firmly in the warmer tier of the annual calendar. The month records approximately 9 sunshine hours per day and 106mm of total rainfall across 11 wet days, giving it a sunshine-to-rain ratio that is broadly workable for most itineraries.
27°C
81°F
Avg High
21°C
70°F
Avg Low
11 days
106 mm total
Rain Days
9h
per day avg
Sunshine
70%
Moderate
Humidity
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. Wind averages 18 km/h, light enough to be refreshing on warm days but noticeable in open coastal areas or elevated viewpoints. In Fahrenheit: 81°F average high, 70°F overnight low. Data sourced from Open-Meteo ERA5 climate reanalysis (1991–2020 normals).
Packing for Shanghai in September means dressing for 27°C days and 21°C evenings. A light cotton tee with a casual overshirt works well at 27°C, the overshirt doubles as a layer for air-conditioned venues. Evening temperatures settle at 21°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. A compact foldable umbrella weighs almost nothing and earns its keep across 11 potential rainy days. 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 Shanghai's heritage areas. A lightweight scarf or sarong weighs almost nothing and solves the problem instantly.
September has no major festivals or public holidays in Shanghai, 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.
Based on 27°C average highs and 11 rainy days
Shanghai'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 27°C with high moisture in the air. Overnight temperatures remain elevated at 21°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.
Shanghai in September
September ranks 4th sunniest of the year in Shanghai, with an average 9 daily sunshine hours. The driest months are October, December, and November. July is the hottest month (31°C avg high); January is the coolest (8°C). From here, temperatures fall 5°C into October. Compared to last month (August: 31°C high, 16 rain days), September is cooler and drier. September sits in the middle of the annual sunshine ranking for Shanghai, offering a reasonable balance of good weather and manageable crowds.
| Month | High | Low | Rain Days | Sun | Details |
|---|---|---|---|---|---|
| January | 8°C | 1°C | 8 | 6h | View |
| February | 10°C | 3°C | 9 | 6h | View |
| March | 14°C | 7°C | 11 | 7h | View |
| April | 19°C | 12°C | 10 | 8h | View |
| May | 24°C | 17°C | 10 | 9h | View |
| June | 27°C | 21°C | 15 | 8h | View |
| July | 31°C | 25°C | 14 | 10h | View |
| August | 31°C | 25°C | 16 | 10h | View |
| September | 27°C | 21°C | 11 | 9h | View |
| October | 22°C | 16°C | 6 | 8h | View |
| November | 17°C | 10°C | 7 | 7h | View |
| December | 11°C | 4°C | 6 | 7h | View |
January
8 rain days, 6h sun
February
9 rain days, 6h sun
March
11 rain days, 7h sun
April
10 rain days, 8h sun
May
10 rain days, 9h sun
June
15 rain days, 8h sun
July
14 rain days, 10h sun
August
16 rain days, 10h sun
September
11 rain days, 9h sun
October
6 rain days, 8h sun
November
7 rain days, 7h sun
December
6 rain days, 7h sun
Data Sources for Shanghai
Climate normals represent 30-year averages (1991-2020). Individual years may vary.