Guerilla Rain is what they call those sudden fierce downpours that seem to be getting more and more common. What we’d call flash floods I suppose. In July they had an attack in Kobe, where four people were swept away, then in Tokyo five sewer workers.
Last Thursday night we had a taste here in Nagoya. It suddenly started pouring, water came in under out garage shutter, and while we were nervously watching the TV news we noticed a pool forming under out living room window. I ran out and pulled off the dead leaves that were blocking the drain hole of our veranda (got soaked in the 3~4 seconds that it took) and the 15cm of water that had built up soon went down… They were saying later that in Nagoya about 100mm of water fell in that hour. Down the road in Okazaki they got 140mm, many houses were flooded, and again two people were drowned. One old lady was found washed up on the coast 40 Km away. More recently, some places in the area have had 400~odd mm of rain in 24 hours.
These are serious quantities of rain when you think about it. 500mm is half a metre of water spread over many square kilometres. No wonder little streams turn into raging torrents, and mountains crumble. While Japan certainly gets plenty of rain, this is unusual for August, or any time for that matter. The cause seems to be that the Pacific high pressure area that usually brings the hot but clear Summer weather has given up, swathes of hot moist air are coming up from the South and colliding with cold air from the Asian continent – right here.
Still, there have been no typhoons up this way so far (touch wood) so we’re luckier than people in the Caribbean who seem to be getting hit by one cyclone after another, not to mention India, where a river has changed course. Back in the day, everything used to be blamed on The Bomb, now it’s Global Warming, though that seems more credible.