The Japan Meteorological Agency issued landslide and wave warnings for the Kanto region as Typhoon No. 6 approached on June 27, 2026.
These warnings are critical because the typical clear weather following a typhoon will not occur. Instead, a rainy-season front moving north is trapping moisture over the region, increasing the likelihood of flash floods and soil instability.
The center of the typhoon reached the waters offshore of Shizuoka at approximately 6 p.m. JST on June 27 [1]. Weather authorities said that rainfall intensity was expected to peak between 6 p.m. and 8 p.m. JST on that same day [4].
In response to the conditions, officials issued a Level 4 landslide-danger warning for Shizuoka, the Izu Islands, Kanagawa, and Chiba [2]. A wave warning was also issued for the Kanto coastal area to protect residents and maritime operators from dangerous sea states [3].
Forecasters said that record-breaking heavy rain on June 27 has left the ground softened [5]. Because of this saturation, the risk of landslides is expected to persist through June 28 [5]. The interaction between the typhoon and the advancing rainy-season front means that the Kanto region will remain cloudy and prone to sudden rain showers through Sunday.
Authorities continue to monitor the Izu Islands and surrounding coastal areas as the system progresses. Residents in the affected prefectures are advised to remain vigilant and follow local evacuation orders if the soil stability worsens.
“A rainy-season front moving north is trapping moisture over the region.”
The absence of 'typhoon-after' clear skies indicates a complex meteorological interaction where a seasonal front reinforces the storm's impact. This creates a prolonged period of instability, meaning that the danger to infrastructure and human life does not end once the typhoon's center passes, but rather extends as the ground remains saturated.
