Japanese weather forecasters are warning of a persistent heat wave with temperatures approaching 40°C across regions from Kyushu to Kanto [1].

The extreme heat poses significant public health risks, while simultaneous threats of thunderstorms and landslides create a complex emergency landscape for local authorities.

For Friday, July 10, temperatures across Kyushu and Kanto are expected to reach approximately 37°C [1]. Specific forecasts include 39°C in Kofu [1] and 36°C in Kumamoto [1]. Actual observations on Friday showed 35.3°C in Hita, Oita, and 35.1°C in Dazaifu, Fukuoka [3].

“Today, from Kyushu to Kanto, the weather will be sunny and the dangerous heat will continue,” a TBS NEWS DIG weather report said [1].

The heat is expected to intensify over the coming days. Forecasts for the weekend of July 13-14 indicate that parts of Kyushu may see temperatures near 40°C [1]. Some reports suggest Kumamoto specifically could reach that threshold [2].

Beyond the heat, other meteorological threats are emerging. The Kanto region faces a risk of thunderstorms during the afternoon hours [1]. Meanwhile, the Tohoku and Hokuriku regions are under alert for landslides [1]. Forecasters said this risk is elevated because previous heavy rains have loosened the ground in those areas [1].

“Today, the 10th (Friday), temperatures are rising rapidly from Kyushu to Tohoku,” weather forecaster Ito said [3].

Local residents are advised to take precautions against heatstroke as the high-pressure system maintains its grip on the archipelago.

““Today, from Kyushu to Kanto, the weather will be sunny and the dangerous heat will continue,””

The convergence of extreme heat and geological instability underscores the volatility of Japan's summer weather patterns. The risk of landslides in Tohoku and Hokuriku, triggered by prior saturation, demonstrates how sequential weather events can compound danger even after the initial rain has stopped.