The Japan Meteorological Agency on Sunday morning issued Level 5 heavy rain emergency warnings, the highest-level alert, to three cities in Fukui Prefecture, saying the risk of landslides and flash floods is increasing.
The municipalities affected were the cities of Fukui, Ono and Katsuyama. The JMA lowered the warning to Level 4 later in the morning.
“Warm, humid air from the south is flowing into a rain front extending from the Sea of Japan to the Fukui area, circling the edge of the high-pressure system on the Pacific Coast,” explained Takuya Hosomi, a JMA official. “This has led to the development of cumulonimbus clouds.”
A cumulonimbus cloud develops dramatically in the vertical direction as a result of strong updrafts, causing what Japan calls “guerrilla rainstorms” and heavy downpours.
The weather conditions are similar to those on Thursday, when Level 5 emergency warnings for heavy rain were issued to five municipalities in Toyama and Ishikawa prefectures.
The affected areas have been hit by extremely heavy downpours of 50 to 60 millimeters per hour, on and off, for an extended period since Saturday night.
Land ministry officials are calling on people to stay away from rivers, irrigation canals and flooded roads.
Rainfall in the 24 hours through 6 a.m. on Sunday reached 300 mm in Katsuyama and 233 mm in Ono, both the highest on record. In the Miyama district of Fukui, rainfall totaled 245.5 mm in the same period.
Translated by The Japan Times
