Japan is preparing for a Sunday of extreme weather, with dangerous heat in the west and heavy rain in the north [1].
These divergent conditions pose significant risks to public health and safety, ranging from heatstroke in urban centers to potential flooding and lightning strikes in rural regions [1], [2].
TBS NEWS DIG said that atmospheric instability combined with seasonal summer heat will drive the volatility [1], [3]. In western Japan, temperatures are expected to reach critical levels. Nagoya is forecast to hit a high of 38 °C [1]. Other cities in the west are also facing intense heat, with Okayama and Kagoshima both predicted to reach 37 °C [1]. Osaka and Hiroshima are forecast to hit 36 °C [1].
Further south, Naha is expected to reach 33 °C [1]. Meanwhile, Tokyo's forecast high is 34 °C [1].
In contrast, the Tōhoku and Hokuriku regions are warned of heavy rain accompanied by thunder [1], [2]. These northern and coastal areas are seeing significantly lower temperatures. Aomori is forecast at 27 °C [1], while Niigata is expected to reach 28 °C [1].
Other regional forecasts include Nagano and Kanazawa both hitting 31 °C [1]. In the far north, Sapporo, Morioka, and Sendai are all predicted to reach 25 °C [1]. Kushiro is expected to be the coolest major city with a high of 20 °C [1].
Weather officials said caution is advised regarding rapid changes in weather patterns during the afternoon [1], [2]. The instability is expected to create sudden shifts between intense heat and severe thunderstorms, a pattern that can complicate emergency responses and travel.
“Nagoya is forecast to hit a high of 38 °C.”
The simultaneous occurrence of extreme heat in the south and severe thunderstorms in the north highlights the volatility of Japan's summer weather. When atmospheric instability meets high seasonal temperatures, it creates a high-risk environment where urban heat islands in cities like Nagoya can become life-threatening, while northern regions face sudden flash flooding risks.
