天気と災害の情報共有

Few people probably remember that there were once only two types of weather warnings; please note that this is not intended to stir up generational differences. In the August Reiwa 8 Chiba heavy rain, a Level 5 Special Warning was issued over a vast area from Ichikawa City to the entire Chiba City area and the surroundings of Kashiwa City. The next day, Level 5 warnings were also issued in Ishikawa, Toyama, and Fukui Prefectures, and numerous Level 4 Danger Warnings followed in other regions. Originally, Level 5 is a major disaster that occurs once every 10 years, and the issuance of a Level 5 warning is reasonable considering the observed scale of damage. On the other hand, misunderstandings that Level 4 is safe, or even that Level 3 is okay, are also a concern. Level 3 corresponds to the warning in the sense of the former maximum alert. It is necessary to recognize anew that the issuance of this itself is unusual. Considering that it is a precursor to higher-level danger warnings or special warnings, it would be advisable to be aware that the issuance of Level 3 could mean a potential escalation to Level 4. Changes in awareness do not happen overnight. Although heavy rain continues at present, please pay attention to weather warnings and advisories again. It is also necessary to utilize weather radar and make efforts to quickly obtain information about when it will rain at your current location in the coming hours.

A Level 3 heavy rain warning has been issued. In mountainous areas like mine, the risk of rockfalls and landslides is high, so it's important to refrain from traveling. Also, although underpasses are few, the terrain is very uneven, so staying in low-lying areas is extremely dangerous. After the rain stops, dense fog often forms, so please be careful.

In the heavy rains of August 2026 in Chiba, two precious lives were lost in underpasses within Chiba City. In response, the Chiba National Highway Office had announced that they would implement preemptive traffic control for underpasses in affected areas whenever a Level 4 heavy rain warning was issued. The autumn rain front, influenced by warm winds from the south feeding into Typhoon No. 24, caused concentrated downpours along the Pacific coast. Chiba City is now implementing the announced underpass entry restrictions. The national government has also taken notice of this nationwide first initiative by the Chiba National Highway Office, deciding to uniformly impose traffic restrictions on national highway underpasses that have experienced flooding at least once in the past. While this was expected to curb damage, an underpass accident occurred in Iwaki City, Fukushima Prefecture. Regardless of whether the road in question was subject to restrictions, caution is necessary for similar incidents across the country. According to traffic experts, it's particularly easy to mistakenly believe you can pass through at night due to the reflection of car headlights. There are also frequent cases where people assume they can go through because the car ahead did, but in reality, only the following cars get caught due to reasons like rising water levels over time. Drivers need to pay attention to weather information and make an effort not to choose the shortest route. It's important to be conscious from before about avoiding low-lying areas like underpasses during rain or at night.