Although not unheard of in the region, the number of waterspouts that have occurred so close to each other is unusual, experts say. Photo courtesy of RAJA/Finnish Border Guard
July 19 — Typically, when stormy weather is forecast, many people avoid the beach or boat trips. However, that was not the case for many holidaymakers in southwestern Finland who rushed to the sea to witness an awe-inspiring weather phenomenon last weekend.
As a storm rolled in and the sky darkened, Nina Rantanen, a holidaymaker in Kustavi on Finland’s southwest coast, gazed in awe at five waterspouts began to swirl in the sea. Rantanen quickly grabbed his phone to capture the spectacular moment.
Rantanen told local media as people lined up to watch the huge waterspouts spin in the distance. She said some were narrower while others “were definitely louder.”
According to AccuWeather Senior Meteorologist Tyler Roys, an area of low pressure moving away from southern Finland and Russia, as well as another area of low pressure moving up the Russian-Baltic border, were the catalysts for the unstable weather and the unusual spectacle.
Just southeast of Kustavi – off Isokari, an island off Finland’s southwest coast – a cargo ship encountered the same weather. Jeffery Ripson, the ship’s captain, told Storyful that his crew members witnessed an unusual phenomenon on July 9.
Crew members aboard the ship hastily grabbed their phones to capture the moment three swirling waterspouts simultaneously hit the sea.
Ville Siiskonen, a meteorologist at the Finnish Meteorological Institute, told local media that these waterspouts are particularly dangerous for boats on the water. Even a small waterspout can collect enough water to capsize boats in the water.
As the weekend drew to a close, stormy weather remained and more waterspouts were reported.
On 11 July, a member of the Finnish border guards observed until seven simultaneous waterspouts off the northern part of Åland, a group of islands off the southwestern coast of Finland.
“Waterspouts are tornadoes that occur over water,” Roys explained. “They tend to occur following showers or thunderstorms.”
Waterspouts can also form when there is no thunderstorm and conditions are ideal. “Fair weather” waterspouts can develop when there are large air and water temperature differences and typically occur in the Great Lakes in the United States.
Although not unheard of in the region, the number of waterspouts that have occurred so close together is unusual.
“It was rare to see so many waterspouts in such close proximity,” wrote the Finnish Meteorological Institute.
Since 1980, there have been around 100 waterspouts reported in this region, according to the European Severe Weather Database. According to Roys, given the nature of not reporting severe weather for much of the 40-year period, that number is likely an undercount and there were likely more waterspouts than 100.