Hail Takes Bangkok by Surprise During the Rainy Season
BREAKING
Residents in several parts of Bangkok were caught off guard on Thursday when an afternoon storm brought an unusual sight with it: hail falling alongside heavy rain.
Reports and videos quickly appeared on social media as people in areas including Ratchadapisek, Chatuchak, Lat Phrao and Chokchai 4 documented the unexpected weather.
Although hail is commonly associated with powerful summer thunderstorms, the phenomenon is relatively unusual in Bangkok during the rainy season.
How did the hail form?
According to Somkuan Tonjan, director of the Aeronautical Meteorology Division at Thailand’s Meteorological Department, the storm developed under atmospheric conditions capable of producing hail despite the time of year.
The key factor was the development of large cumulonimbus clouds, the towering storm clouds capable of producing intense rainfall and strong vertical air movements.
Moisture carried by the southwest monsoon combined with high temperatures to fuel the development of these clouds. Inside them, strong upward currents can lift tiny water droplets high into the atmosphere, where temperatures are below freezing.
The droplets can then freeze into small pieces of ice.
As the particles move repeatedly through different parts of the cloud, additional layers of water can freeze onto their surfaces. Once the ice becomes too heavy for the rising air to hold up, it falls toward the ground as hail.
An unusual but relatively mild event
While hail outside the usual summer storm season is uncommon, Somkuan said Thursday’s weather event was not as intense as the hailstorms that can occur during the hotter months.
The unusual combination nevertheless caught the attention of Bangkok residents, many of whom recorded the brief phenomenon and posted their footage online.
Meteorologists continue to monitor conditions as moisture remains over the capital.
Residents warned not to eat the hail
The small pieces of ice may look harmless, but the Meteorological Department advises people not to consume hail collected from the ground.
As hail forms and falls through the atmosphere, it can come into contact with airborne particles and pollutants. Dust, chemicals and other contaminants can become trapped in or deposited on the ice before it reaches the ground.
For that reason, what looks like a clean piece of ice should not necessarily be considered safe to eat.
More rain expected in Bangkok
The unusual hailstorm does not signal the end of Bangkok’s rainy conditions.
The TMD expects light to moderate afternoon showers to continue through October 4, with moist winds remaining over the capital.
Some locations could receive more than 35 millimetres of rain, although the showers are expected to be relatively short-lived rather than producing the prolonged rainfall seen in previous weeks.
For Bangkok residents, Thursday’s storm provided an unusual reminder that even during a familiar rainy-season pattern, the city’s tropical weather can still produce a few surprises.