At noon on March 27, a massive elongated cloud appeared in the sky over Jiaxing, Zhejiang, stretching dark and heavy across the horizon, resembling a giant serpent in the sky.

Eyewitnesses reported that the cloud was approximately 20 meters long and lingered for about 20 minutes before a brief period of rain followed.

According to experts, this strip-like cloud formation may have been caused by the following factors.

When strong moisture transport encounters the mountainous terrain of western and central Zhejiang, the airflow is lifted, creating oscillations that result in alternating cloud bands and cloudless areas. These clouds appear in streaks, resembling "spring rolls," and often signal prolonged rainy weather. This phenomenon is linked to a sudden increase in atmospheric moisture and energy accumulation.

During spring and summer, frequent clashes between warm and cold air masses can create narrow, elongated cloud bands. These cloud systems are often accompanied by thunderstorms or short bursts of heavy rainfall. Due to density differences, the clouds appear darker and tend to move rapidly.