Summer is definitely here. For the last two days, the temperature in central Tokyo peaked somewhere over 35°C. North of Tokyo, in the mountains of Gunma-ken, 900 people were hospitalised and 2 died from heatstroke. It's rather hot, to say the least. It's also very humid (between 50% ~ 95% RH).
The strong sun easily burns, and it's not uncommon to see ladies with parasols. The heat causes the moist air to rise high, creating these magnificent cumulonimbus clouds. When I took this photo, we could already hear the thunder in the distance. Two hours later, the thunder was above us, and we endured another huge thunderstorm.