Japan: High temperatures are forecast to persist across most of the country through at least July 5

Forecast models indicate that high temperatures will persist across much of Japan through at least July 5. As of June 24, the Japan Meteorological Agency (JMA) has issued heat stroke alerts across Kagoshima and Ibaraki prefectures and Yaeyama Islands in Okinawa Prefecture. High temperatures are likely across most of the rest of Japan through at least July 5. Authorities may update, extend, or rescind advisories as weather conditions change over the coming days.

The extended period of oppressive heat and dry conditions may produce ideal circumstances for wildfire growth throughout the region. Heatwaves also threaten vulnerable groups - such as the elderly, children, pregnant women, and those with respiratory illnesses - due to the increased possibility of heat stroke or heat exhaustion during prolonged exposure to high temperatures. These health risks could also affect relatively healthy individuals during significant heatwave events.

Very high temperatures could warp rail tracks and force passenger and freight trains to operate at reduced speeds. Damage to road surfaces is also possible, and overheated vehicles could worsen traffic problems in urban areas where congestion is already a problem. Commercial trucking disruptions might occur, as very high temperatures put more stress on vehicles and make tire blowouts more common. Major flight disruptions are unlikely at regional airports; however, general aviation disruptions are possible, and some air freight carriers could reduce cargo loads. High temperatures could lead to an increased demand for electricity, which might trigger localized brownouts or blackouts, exacerbating hazardous conditions when air conditioning is no longer possible.