Hong Kong’s No 2 official has responded to parents’ concerns about the suspension of day schools on Friday despite the fine weather, saying it was a difficult decision due to the low predictability of rainstorms and the wish by authorities to be “safe than sorry”.

Chief Secretary Eric Chan Kwok-ki, who chairs the steering committee on handling extreme weather, said the government had decided to halt certain classes due to the local forecaster predicting that Hong Kong could have faced its fifth-largest rainfall, or 390mm (15.4 inches) a day, in an “extreme” case.

The predictions factored in the effects of remnants of then tropical cyclone Danas, which brought heavy showers and thunderstorms to the city.

“Therefore, we chose to issue early warnings and make proactive preparations, even if it meant ‘doing too much’, even if the safety margin was excessively large, and even if volatile weather might lead to forecast deviations,” Chan said in a social media post.

“We would rather be safe than sorry.”

Chan also cited the challenges of predicting rainfall, noting the task was much more difficult than forecasting typhoons, even with the existing technologies.