A heatwave impacting Europe is forecast to extend into Finland this weekend, according to meteorologist Sara Salonen of Foreca. The arrival of warm, humid air also increases the likelihood of thunderstorms. While the weather will remain variable throughout the week with approaching rain systems from the west, drier periods are expected in between. A strengthening high-pressure system from the south will bring exceptionally warm air for the weekend. The combination of heat and humidity creates conditions conducive to thunderstorm development. Forecasters anticipate significant temperature increases as the heatwave settles over the region.