Japan Weather Forecast: Heavy Rain Warnings for May 1st and Golden Week Outlook

Weather forecasts for May 1, 2026, indicate that a wide area of Japan, including North Japan, East Japan, and the Kinki region, will experience significant rainfall accompanied by strong winds.

Reporting from WeatherNews and Yahoo! News indicates that the weather conditions on May 1 are expected to reach warning levels, with specific cautions issued for heavy rain and intense wind gusts across these regions.

Severe Weather Warning for Nagano Prefecture

The Nagano Local Meteorological Observatory has issued a specific alert for Nagano Prefecture, noting that atmospheric conditions are expected to be extremely unstable from the late morning of May 1 through late night.

According to the observatory, residents and visitors in the region should be alert for several severe weather phenomena, including:

• Lightning strikes
• Intense gusts, including the potential for tornadoes
• Hail
• Sudden, heavy rainfall

Golden Week Outlook

The unstable weather is expected to persist through portions of the Golden Week holiday period. While May 1 will see widespread rain, WeatherNews reports that precipitation is forecast to return on May 3, 2026, and May 4, 2026.

However, the forecast suggests a shift in conditions toward the end of the holiday, with sunny weather expected to prevail during the final stages of Golden Week.

Long-term Temperature Trends

Beyond the immediate holiday weather, the Japan Meteorological Agency (JMA) has released a one-month forecast indicating that a trend of high temperatures is expected to continue.

In light of these projected temperatures, the agency has advised the public to take comprehensive precautions to prevent heatstroke.