Climate and monthly weather forecast
Ya'an, China

As classified by the Köppen climate classification, Ya'an, China is situated under the Cwa category boasting a humid subtropical climate. Much like the apt description, it experiences a distinctive dry winter season, while the summer is generally hot and humid. Throughout the year, there is considerable oscillation in the weather parameters including the amount of rainfall, temperatures, and daylight hours.

In terms of temperature, the annual fluctuations range from 4.1°C (39.4°F) to 29.6°C (85.3°F) reflecting the city's subtropical climate. During the year, Ya'an also witnesses a significant fluctuation in rainfall. On one end, the driest month records rainfall of 21mm (0.83") while on the other end, a high of 434mm (17.09") of rainfall is experienced. Daily sunlight duration varies between 10.2 hours to 14.1 hours, with the longest sunshine hours occurring in the summers.

An unusual weather pattern observed in Ya'an is that of sustained high humidity and heavy rainfall during summers. This can be corroborated with months of June through September experiencing the highest rainfall. Correspondingly, the onset of winter switches the rainfall tables, as Ya'an experiences a dry winter, thus justifying its Cwa climate classification.

Given the climatic data and the weather trends, the most advisable time to plan a visit to Ya'an would arguably be between the months of April and May. In these months, the average temperatures hover around a comfortable 15.6°C (60.1°F) to 21.5°C (70.7°F). The rainfall is moderate, falling between 51mm (2.01") and 93mm (3.66"), making this time relatively dry compared to other months. Coupled with the average daylight duration extending from 12 hours to 12.9 hours, tourists can make the most out of their day exploring Ya'an.

Contrasting the best time, the period stretching from June to September would typically be considered less optimal for visiting Ya'an. This assertion is based on multiple factors. To begin with, the mercury rises substantially during these months leading to high temperatures that may stretch up to 29.6°C (85.3°F). Furthermore, Ya'an receives an exceptionally high rainfall ranging from 181mm (7.13") to a staggering 434mm (17.09"), which can restrict outdoor activities.

Spring in Ya'an rolls in around March and continues until May. During this period, Ya'an experiences a mild rise in temperature. The average high and low temperatures range from 15.6°C (60.1°F) to 25.5°C (77.9°F) and 8.8°C (47.8°F) to 17.5°C (63.5°F), respectively. Correspondingly, as the spring season continues, there is an increase in average rainfall, from 51mm (2.01") to 93mm (3.66") to 129mm (5.08"), suggesting a gradual thickening of the clouds across these months. The daylight hours also see a rise from 12 hours to 13.7 hours.

Summer saunters into Ya'an from June and stays till September. During these months, the city grapples with high temperatures that average between 24.9°C (76.8°F) and 29.6°C (85.3°F). The nights are relatively cooler, with temperatures dropping to an average of 20.2°C (68.4°F) in June and slightly higher at 21.9°C (71.4°F) in September. This period registers the highest rainfall of the year, starting from 181mm (7.13") and soaring up to 434mm (17.09") in August.

Autumn stretches from October to November in Ya'an. During this time, temperatures witness a gradual dip, with the daytime high dropping from 24.9°C (76.8°F) to 15.5°C (59.9°F) and the nighttime low settling between 18.5°C (65.3°F) and 10.3°C (50.5°F). The rainfall also reduces significantly during these months, from around 207mm (8.15") in the initial month to 57mm (2.24") by November's end.

Come December, winter sets in Ya'an and continues into February. This period marks the coldest temperatures of the year, plunging to a low of 4.1°C (39.4°F) and reaching a high of 11.1°C (52°F). The rainfall is the least during these months, with the monthly average falling as low as 21mm (0.83") in December and 32mm (1.26") in February. Despite the colder weather, the daylight hours remain fairly consistent, averaging between 10.5 hours to 11.1 hours.

January ushers in the New Year with temperatures ranging from 4.1°C (39.4°F) to 9.4°C (48.9°F). The winter chill in Ya'an, China remains firmly in place throughout the month. Days are quite short, with only around ten hours of sunlight. Weather in January »

The month of February observes a slight increase in temperatures compared to January. Ya'an weather starts preparing to transition from winter to spring. Rainfall becomes more frequent, and the days get a bit longer as well. Even though it isn't yet spring, it is not as cold as the previous month. Weather in February »

March in Ya'an, China, sees temperatures further rising from 8.8°C (47.8°F) to 15.6°C (60.1°F). The weather starts to get warmer, signifying the arrival of spring. Rainfall continues to increase, and daylight extends a bit more, making days longer. Weather in March »

As April progresses, the temperatures in Ya'an continue to rise, ranging from 13.5°C (56.3°F) to 21.5°C (70.7°F). It's the ideal time to experience the warmth of spring with a higher temperature than in March. Despite the increase in temperature, rainfall does not subside, it significantly escalates instead. Weather in April »

The month of May witnesses a significant jump in temperature to the range of 17.5°C (63.5°F) to 25.5°C (77.9°F) in Ya'an, China. It marks the transition from spring to early summer. Rainfall peaks towards the latter half of the month. Weather in May »

June signals the advent of summer in Ya'an with temperatures ranging from 20.2°C (68.4°F) to 27.7°C (81.9°F). The shift from May to June brings a substantial increase in temperature. However, it is accompanied by a sharp increase in rainfall, which can dampen summer activities. Weather in June »

The heat continues to sizzle in Ya'an throughout July with temperatures peaking at around 29.6°C (85.3°F). It is officially the height of summer. However, in addition to experiencing the highest temperatures, it is also inundated with an annual high of 370mm (14.57") rainfall. Weather in July »

Even though the temperatures remain high at around 29.6°C (85.3°F), August in Ya'an, China, brings the heaviest rainfall of the year at 434mm (17.09"). Despite the constant rain, the heat of the summer persists. The number of daylight hours steadily declines as the month progresses. Weather in August »

September brings respite from the summer heat as temperatures start to drop to the range of 18.5°C (65.3°F) to 24.9°C (76.8°F). The warmth of summer starts to give way to the coolness of autumn in Ya'an, China. Rainfall drops significantly compared to the month of August. Weather in September »

October witnesses a significant decrease in temperature from 14.5°C (58.1°F) to 20.1°C (68.2°F) compared to September. The touch of autumn is evident in Ya'an's climate. The decrease in rainfall adds a crisp touch to the air. Weather in October »

November's weather sees further decrease in temperature range from 10.3°C (50.5°F) to 15.5°C (59.9°F) in Ya'an, China. A dramatic shift from the mild autumn to the cold winter takes place throughout the month. There is a sharp reduction in rainfall compared to October. Weather in November »

December marks the coldest month of the year with temperatures ranging from 5.8°C (42.4°F) to 10.8°C (51.4°F). The chill of winter is now fully installed in Ya'an. A decrease in rainfall mirrors the drying cold of the weather. Weather in December »