Bangkok’s floodwater recedes, but the Pacific is not done misbehaving

Bangkok spent the end of last week doing what no capital city wants to do: floating. City officials declared it a disaster zone after streets were submerged in flood water as high as a person’s waist, the result of an active low-pressure cell over central Thailand. The weather, in its usual unsentimental way, had no interest in urban planning.

The rain started early on Thursday, when the weak low-pressure area moved north-westwards up the Gulf of Thailand and then parked itself over central Thailand by Friday morning. It stayed there for most of the next two days, which gave Bangkok and nearby areas a steady dose of thunderstorms and downpours. Near Prachin Buri, just north-east of the capital, one weather station recorded 213.5mm in 24 hours between Friday and Saturday evening local time. London, by comparison, gets about 585mm in a year.

By Sunday, the centre of the system had shifted north-westwards, and the worst of the rain was over. That did not erase the damage, but it at least ended the prolonged soaking that had turned roads into waterways. Bangkok’s disaster declaration was hardly theatrical; it was simply the administrative version of stating the obvious.

While Thailand was drying out, Hawaii’s Big Island was dealing with Hurricane Nolo. The system had already approached the archipelago early last week and began bringing heavy rainfall from Tuesday evening. By the early hours of Saturday, Nolo had become a category 2 hurricane, with sustained winds of 85-90 knots, or 98-104mph, and was then about 145 miles south of the Big Island.

Wind was only one part of the problem. Since Nolo’s impacts began on Tuesday 22 September, weather stations in the north-east of the island have recorded more than 530mm of rain, raising concerns about flooding and mudslides. The storm was then forecast to move westwards away from Hawaii, where it was expected to peak in intensity on Monday 28 September and reach category 4 status.

Farther east, Hurricane Polo was forecast to make landfall on the Baja California peninsula late on Monday 28 September. The storm, once a category 5 system, was expected to weaken to category 2 by the time it reached land, with sustained winds of 96-110mph. Coastal areas were placed under a hurricane warning because of the risk of storm surge where winds are onshore.

Polo was also expected to dump heavy rain across the peninsula, with 100-200mm forecast and local totals possibly reaching 250mm. Much of that was due to fall within 12 hours, which is usually a bad sign if one enjoys roads, slopes and other fragile arrangements. The storm was then expected to continue weakening as it moved north-eastwards across Mexico’s Sonora region.

Written by Martina Kirchner martina.kirchner@alpineweekly.com