Summer may not be officially over but Dutch weather forecasters are already making up the balance for the past three months.

According to weather bureau weeronline.nl, this has been a summer of extremes, with tropical temperatures interspersed with cold days and torrential rain. The six warm spells were all followed by chilly days and heavy storms, weeronline said on Wednesday.

However, thanks to reasonable weather in August, the summer has been slightly warmer than average at 17.5 degrees. And despite the rain, it was also sunnier than normal, with 670 hours of sunshine compared with an average 608. June in particular was bright, weeronline said.

The temperature tipped 30 degrees on five days in the country as a whole, but Limburg was much hotter with 13 officially tropical days.

In terms of rainfall, the summer has also been wetter than average, with 260 millimetres of rain, 3.5 centimetres more than normal. That total is set to increase over the next few days and 2015 could end up as one of the wettest summers on record, weeronline said.