Gansu Climate

Gansu Province (甘肃省) has one of the most geographically complex climates in China. Stretching for more than 1,600 kilometers from east to west, the province lies where the Qinghai–Tibet Plateau, Loess Plateau and Inner Mongolian Plateau meet. Within a single province, travelers can encounter desert and Gobi landscapes, oasis basins, loess hills, deep subtropical valleys, alpine grasslands and snow-covered mountains.

This geography creates Gansu’s defining climate pattern: wetter and warmer toward the southeast, progressively drier toward the northwest, and increasingly cold with elevation in Gannan and the Qilian Mountains. Official climatic zoning broadly divides Gansu into the Longdong–Longxi Loess Plateau, Longnan–Gannan–Qilian mountain/highland region, and Hexi desert region. Long-term precipitation ranges from only about 40–200 mm in the Hexi desert belt to around 700–800 mm in wetter parts of Longnan, while alpine Gannan commonly receives 500–600 mm.

🏔️ How Geography and Landforms Shape Gansu’s Climate

The East–West Dryness Gradient

Gansu lies deep inside the Eurasian continent, far from the ocean. Moist summer air can still reach Longnan, Tianshui, Pingliang and Qingyang, but its influence weakens dramatically farther west.

Consequently, southeastern Gansu has forests, river valleys and relatively humid summers, while Jiuquan, Dunhuang, Jiayuguan and western Zhangye have extremely dry continental conditions. Long-term provincial data show annual precipitation varying from only a few dozen millimeters in the driest western areas to well above 700 mm in the southeast.

Altitude and the Tibetan Plateau

Elevation is equally important. Gannan Tibetan Autonomous Prefecture and the Qilian Mountain areas generally lie above 3,000 meters, causing much lower temperatures than places at similar latitude in the Hexi Corridor.

Summer days on the Gannan grasslands may remain around 15–22°C while lower-elevation cities experience temperatures close to or above 30°C. Nights remain cool even in July and August, while snow, frost or rapid cold spells can occur much earlier in autumn and later in spring.

The Qilian Mountains and Hexi Oases

The Qilian Mountains form the southern wall of the Hexi Corridor. Snow and glaciers feed rivers that descend toward Wuwei, Zhangye, Jiuquan and other oasis settlements, allowing agriculture and cities to exist within an otherwise arid landscape.

The corridor itself is confined between mountain systems and desert basins. Strong pressure differences and funneling effects contribute to frequent wind, blowing dust and sand, particularly in spring. The Hexi desert region receives only about 40–200 mm of precipitation annually but experiences strong solar radiation and very large day–night temperature ranges.

Longnan’s Deep Valleys

Longnan is completely different. Its mountains belong to the western extension of the Qinling system, with deeply incised valleys producing strong vertical climatic zoning. Lower valleys can experience warm-temperate and even northern-subtropical conditions, while surrounding mountains are much cooler.

Official environmental data describe Wudu and surrounding areas as transitional between northern subtropical semi-humid and warm-temperate climates, with rainfall heavily concentrated from July to September.

🌡️ Climate by Major Region of Gansu

These figures describe long-term climatic zones rather than the weather of any individual year. Gansu’s elevation changes are so large that temperatures can vary by 15°C or more on the same day between a desert basin and nearby high mountains.

📅 Gansu Monthly Temperature and Climate Table

Because Gansu is too geographically diverse for one city’s figures to represent the entire province, the following ranges are travel-planning reference temperatures rather than a formal province-wide monthly average.

The key point for international travelers is that daily temperature range matters almost as much as average temperature. A 25–30°C afternoon in Dunhuang or Zhangye can be followed by a much cooler evening, while temperatures on the Gannan Plateau can fall rapidly after rain.

Recent Climate Trends and Weather Extremes

Gansu has experienced a notable warming tendency in recent years. In 2024, the province-wide annual average temperature reached 9.7°C, 1.2°C above the climatic normal and the highest recorded since 1961. Provincial annual precipitation reached 434.7 mm, while annual sunshine totaled 2,297.2 hours.

That does not mean every year is becoming uniformly warmer and easier for travel. 2025 demonstrated how variable Gansu weather can be: spring precipitation fell to only 51.6 mm, the lowest in 25 years, while strong winds were unusually frequent in April and May. Later in summer, extreme rainfall affected parts of eastern and central Gansu; on August 7, 2025, Xinglongshan near Yuzhong recorded 220.2 mm in 15 hours, more than half its normal annual rainfall and a record-breaking event for the Lanzhou area. Gansu also recorded its highest number of blowing-dust and floating-dust days in roughly 35 years.

For travel planning, long-term climate should therefore be used as a guide rather than a guarantee. Mountain and desert weather forecasts should always be checked immediately before departure.

🌱 Spring Weather: March to May

Spring develops at very different speeds across Gansu. Longnan and Tianshui warm first, while the Gannan Plateau and Qilian Mountains may remain wintry well into April.

Central and western Gansu warm rapidly during the day, but cold air can cause sudden temperature drops. March and April are also the main period for strong winds, blowing dust and sand, particularly around Jiuquan, Jiayuguan, Dunhuang, Zhangye, Jinchang and Wuwei.

May is generally one of the most balanced travel months. Lowland cities are warm without peak summer heat, while grasslands and mountain regions are beginning to turn green.

Clothing: Use layers: long-sleeved base layer, fleece or light sweater and a windproof outer jacket. A light down jacket remains useful in Gannan, high mountain areas and for early-morning desert visits.

Best suited to: Tianshui, Longnan, Lanzhou, Linxia and the Hexi Corridor, especially from late April onward.

☀️ Summer Weather: June to August

Summer produces Gansu’s greatest climatic contrast.

The Hexi Corridor becomes hot, sunny and extremely dry. Dunhuang, Jiuquan and Jiayuguan can experience daytime temperatures above 30°C, and exposed desert surfaces become much hotter than official air temperatures.

At the same time, Gannan becomes one of China’s classic highland summer destinations. Daytime temperatures are usually comfortable, grasslands are green and wildflowers flourish. Nights, however, remain cool.

Summer is also the main rainy season across much of eastern, central and southern Gansu. Long-term water-resource data confirm that precipitation is strongly concentrated in summer and early autumn, particularly east of the Hexi Corridor.

In Longnan, Tianshui, Gannan and mountain areas around Dingxi and Lanzhou, heavy rain can trigger flash floods, landslides, rockfalls and temporary road closures.

Clothing: Short sleeves and lightweight trousers for lowlands, plus SPF50+ sunscreen, sunglasses and sun hat. Carry a waterproof shell. For Gannan and Qilian highlands, pack fleece or a light down jacket even in July.

Best suited to: Gannan and high-altitude landscapes for cool-weather travel; Hexi destinations remain excellent if outdoor sightseeing is scheduled outside the strongest midday heat.

🍂 Autumn Weather: September to November

September and early October are generally the best overall period for traveling across Gansu. Days are often clear, humidity is relatively low and temperatures suit both cultural sightseeing and outdoor activities.

September can still be rainy in Longnan, Tianshui, Pingliang and Gannan, and occasional autumn rain systems affect eastern Gansu. Farther west, the Hexi Corridor becomes increasingly dry and sunny.

By October, temperatures fall quickly at night. Frost becomes common in highland and desert regions, while Gannan and the Qilian Mountains may already experience snow.

Late September through October is especially attractive for autumn colors in oasis, forest and poplar landscapes, although the exact timing changes annually.

Clothing: Long trousers, sweater or fleece and windproof jacket. From October onward, add a light down jacket for western Gansu and a warmer insulated layer for high-altitude regions.

❄️ Winter Weather: December to February

Winter is generally cold, dry and sunny, particularly in the Hexi Corridor and central Gansu. The dry atmosphere often provides excellent visibility, but wind chill can be severe.

The Gannan Plateau, Qilian Mountains and higher parts of Dingxi, Wuwei and Zhangye can fall below -20°C during cold waves. Even lower areas occasionally experience major temperature drops; during a January 2024 cold-wave episode, temperatures at Wuwei fell to -27.6°C.

Longnan is substantially milder, especially in its lower valleys.

Winter has the advantage of low visitor numbers at major cultural destinations, but mountain roads may experience snow and ice and some seasonal tourism services operate less frequently.

Clothing: Heavy down jacket, thermal underwear, insulated trousers, gloves, hat and warm shoes. Moisturizer and lip balm are particularly useful because western Gansu is extremely dry.

Best Time to Visit Different Parts of Gansu

For a trip covering several regions of Gansu, late May to June and September to early October offer the best compromise between western desert temperatures, central-Gansu weather and highland accessibility.

Clothing Guide for Gansu

The most reliable rule throughout Gansu is layering. The province combines strong solar radiation with large day–night temperature differences, meaning travelers may need sunscreen and an insulated jacket on the same day.

Weather Safety for Self-Driving, Cycling and Outdoor Travel

Travelers driving across the Hexi Corridor should pay particular attention to strong crosswinds, blowing dust and reduced visibility in spring. Long distances between towns also make water, fuel and basic emergency supplies important.

In Gannan, Longnan and the Qilian Mountains, summer rain is a more serious issue. Avoid entering narrow valleys, river channels or undeveloped mountain areas during thunderstorms or heavy-rain warnings because flash floods and landslides can develop quickly.

Cyclists and motorcyclists should consider wind chill as well as temperature. A comfortable 15°C afternoon can feel much colder on exposed plateau or desert roads. High-altitude riders should also expect stronger ultraviolet radiation and rapid weather changes.

Winter self-driving requires particular caution on mountain roads, shaded passes and high-elevation sections where snow and black ice may remain even when nearby valley roads are dry.