Climate averages 1991–2020

Ya'an weather
in September.

A warm, very wet month: the 5th warmest and the 10th driest of the year.

Long-term climate patterns, not a forecast for a particular trip.

Average high 23.4°C Daytime mean, September

Average low 18.8°C Night-time mean, September

Rainfall 197 mm 21 days with ≥1 mm

Daylight 12 h Sunrise to sunset, per day

September is a warm month in Ya'an: daytime highs average 23.4°C and nights cool to about 18.8°C. By daytime temperature it is the 5th warmest of the 12 months.

Expect about 197 mm of rain on roughly 21 days, which makes September a very wet month (the 10th driest of the 12 months). Daylight, from sunrise to sunset, lasts about 12 h 22 min on an average September day.

The nearest other city in this atlas is Meishan (81 km away). In September its highs average 25.7°C, 2.3°C warmer than Ya'an, with 120 mm of rain.

Among the 884 cities listed in China, Ya'an ranks joint 680th of 884 for the warmest September highs and joint 837th of 884 for the driest September (rainfall, lowest first). The mean September high of those 884 cities is 25.7°C; Ya'an is 2.3°C cooler than that mean.

From September to October, average highs fall by 4.7°C to 18.7°C, and monthly rainfall falls from 197 mm to 119 mm.

The annual picture

September in context

30-year average

Average highAverage low°C

Monthly rainfall

Average total · mm

Averages from hourly ERA5 reanalysis data. Actual weather varies from year to year. How these numbers are calculated

Every month, side by side

Ya'an climate table

1991–2020

Monthly climate averages for Ya'an, 1991–2020
Month	Average highHigh / low	Average low	Rainfall mm/month	Rain days ≥1 mm/day	Daylight hours/dayDaylight h/day
January	8.3°C2.7°C	2.7°C	45	12.9	10.410 h
February	10.8°C4.5°C	4.5°C	52	13.4	11.111 h
March	15.2°C8.1°C	8.1°C	76	15.2	12.012 h
April	20.2°C12.7°C	12.7°C	104	15.3	12.913 h
May	23.5°C16.5°C	16.5°C	129	17.1	13.614 h
June	26.0°C19.8°C	19.8°C	168	18.2	14.014 h
July	27.7°C21.6°C	21.6°C	284	22.0	13.914 h
August	27.3°C21.3°C	21.3°C	329	22.5	13.213 h
September, selected	23.4°C18.8°C	18.8°C	197	20.5	12.412 h
October	18.7°C14.6°C	14.6°C	119	20.4	11.511 h
November	14.6°C9.8°C	9.8°C	76	15.5	10.711 h
December	9.8°C4.4°C	4.4°C	44	12.4	10.310 h

Rainfall is the average of the 30 separate monthly totals. A rain day is a local calendar day with at least 1 mm of precipitation. Daylight is the calculated sunrise-to-sunset length, not measured sunshine.

Compare places

September in nearby cities

Distance from Ya'an

Read the numbers correctly

Climate, not a promise.

These patterns help compare months. They cannot tell you the weather on a specific day of your trip.

Sources, method and limits

How these numbers are made (what the highs, lows and rain days mean, the sources and the model cell used for Ya'an) is explained once on the Ya'an year overview and on the Sources, method and limits page.