Why does it snow in Beijing in June?

In response to media reports that the sky was snowing on July 30, yesterday, both the China Meteorological Bureau and the Beijing Meteorological Observatory said that the meteorological department did not monitor this situation, and the atmospheric temperature in Beijing was high that day, which did not have the natural conditions for snow. This statement is not reliable.

On July 3 1 day, some media reported that at 6 o'clock in the afternoon on July 30, snow suddenly began to fall near Changhong Bridge in the East Third Ring Road. The whole snowing process lasted about 5 minutes, and the snowflake was about 50 cents in size and melted as soon as it landed.

In this regard, Guo Hu, director of the Beijing Meteorological Observatory, said that on July 30, the Municipal Meteorological Observatory did not monitor the snowfall process described in the report. "It is impossible to snow in Beijing in dog days, which is contrary to common sense." It has never snowed in summer of beijing in history, and the earliest snowfall in Beijing was 65438+ 10.

For the sake of prudence, yesterday morning, the Beijing Meteorological Observatory organized relevant experts to discuss this matter. Zhang Mingying, an expert from the Municipal Meteorological Observatory, said that in summer, cold and warm air convection is intense. When the air suddenly pulls the low-altitude cumulonimbus clouds containing ice crystals or snowflakes to the ground, there may be a small range of short-term snowfall at the low temperature below zero. However, on that day, the zero floor of Beijing's atmosphere was at an altitude of 3,200 meters (that is, the atmospheric temperature above 3,200 meters was zero), and the atmospheric temperature near the ground in Beijing was about 30 degrees Celsius. Such a high temperature does not allow snowflakes to fall slowly.

Zhang Mingying also pointed out that snow in summer will be accompanied by strong winds and sudden drop in temperature. The temperature drops to zero degrees Celsius in a short time, and the contrast between hot and cold before and after will make the human body feel very obvious. However, the report did not describe strong winds and cooling. "It just said that a citizen saw snow at home."

Meteorologists said that from the situation described in the report, it is neither snow nor hail. No matter whether anti-aircraft guns, rockets or planes are used for artificial precipitation enhancement, there will be no foam-like objects. According to their analysis, the rain in Beijing on the 30th was very violent. Larger raindrops are broken when falling rapidly, and it is not excluded that some people mistake the broken raindrops for snowflakes.

Yesterday, Song Lianchun, spokesperson of China Meteorological Bureau and director of the Department of Forecasting and Disaster Reduction, said that China Meteorological Bureau did not monitor the snowfall that day and did not receive relevant reports. Song Lianchun agreed with the Beijing Meteorological Observatory. He also thinks it is impossible for Beijing to snow in dog days.

related data

In the past 20 years, there have been four recorded snowfalls in summer:1981June1June, and heavy snow fell in Guancenshan forest area of Shanxi Province; On June 24th 1987, there was a small snowflake floating in Shanghai. On June 5 of the same year, heavy snow fell in Zhangjiakou, Hebei Province. From 8: 00 on June 18 to the early morning of June 19, there was moderate to heavy rain in Gannan Tibetan Autonomous Prefecture, Gansu Province, and the minimum temperature dropped to above 0℃ and below 1℃. At 5 o'clock on June 19, it turned to snow in Gannan Hezuo and Xiahe areas.