Map from Google - Xian

The climate of Xi'an is continental, with cold, dry winters and hot, humid summers. The city is located in central China, at a latitude not very high, but it is almost a thousand kilometres (600 miles) away from the sea, and is affected by the continentality of the Asian landmass, but also by the Asian monsoon; it is also located at 400 metres (1,300 feet) above sea level. On the other hand, the position in a valley and the distance from the sea make the summer heat intense and annoying, while in winter cold air often stagnates on the ground.
Here are the average temperatures.
Average temperatures - Xian
Min (°C)-4-2391419222115103-3
Max (°C)581420263132312419126
Min (°F)252837485766727059503727
Max (°F)414657687988908875665443

Capital of the province of Shaanxi (Shensi), Xi'an is one of the ancient Chinese capitals, and has several interesting monuments, in addition to the famous Terracotta Army. Today it is a metropolis of millions of inhabitants, polluted as often happens in the big cities of China.
Precipitation amounts to about 580 millimetres (23 inches) per year; due to the monsoon, the rainiest season is summer, while the driest is winter.
Here is the average precipitation.
Average precipitation - Xian
Prec. (mm)61125506555957011065256585

Winter, from December to February, is cold and dry: the average January temperature is 0 degrees Celsius. Precipitation is rare and not abundant, but the sky is often cloudy. However, considering the temperatures, there may be some snowfalls, generally light. The cold wind from the north can bring cold waves, with minimum temperatures dropping to -15 °C (5 °F), as well as the dust of the Gobi Desert. Instead, the winds from the south, which descend from the mountains, can bring mild days, with highs around 15/20 °C (59/68 °F).

In spring, from March to May, the temperature increases, while the rainy days become gradually more frequent. The sunshine amount is just acceptable. In March and April, clashes between air masses can cause sand storms.

Summer, from June to August, is hot and muggy, and it is the rainiest season, as it's influenced by the Asian monsoon. June is already a hot month, but generally the rains and the heat come in July, or during the month of June. The rains have still an erratic pattern from year to year. The sunshine amount is fairly good, indeed summer is the sunniest season, although there are cloudy days even in this season. The rains occur mainly in the form of downpour or thunderstorm. In some years the rains may be abundant, even in September, and in some cases, but more rarely, in October. The periods of good weather during the summer can be very hot, with highs around 38 °C (100 °F), and in these cases the heat does not give relief even at night. August is usually a bit less hot than June and July, but it is more sultry.

Autumn, from September to November, is initially mild, and gradually becomes cooler, and then quite cold in November, but sometimes it can get cold at night already in October. The rains are frequent at the beginning: September is even the wettest month of the year. Rainfall then gradually decreases, while the sky remains often cloudy.

The amount of sunshine, as we have seen, is never very good, although some sunny days can occur throughout the year.

Terracotta army

When to go

The best times to visit Xi'an are spring and autumn, ie the months of April, May and October. In April and October it can sometimes be cold at night, with lows around freezing, while in May and September during the day it can be hot. In general, however, September is avoided because it is a rainy month, with the risk of flooding every so often. Sometimes the monsoon anticipates and already in May it can rain a lot, but usually in spring it rains less than in autumn. Autumn, in September and October, is similar to spring, but it is a season with frequent cloud cover, and it's initially rainy.