rbtfl

Japan's Typhoon 13 Dolphin forms in central Pacific, may hit Japan as super typhoon around the Obon holiday

Japan's Meteorological Agency designated Tropical Storm Dolphin as Typhoon 13 at 15:00 JST July 27, at 13.3°N 176.9°E; forecasters expect it to reach violent super-typhoon intensity by August 1 and diverge on whether it will approach Japan's main islands during the Obon travel period in mid-August

Weather· worsening How Life Changes·The Long Game ·10 takes · ·rbtfl upd Jul 28, 2026
post

The split

The same story, as told by newsrooms in different countries. Their words, attributed and linked.

Japan

Japan Meteorological Agency via TV-U Yamagata / Yahoo Japan

“台風第13号(ドルフィン)が発生しました。台風は1時間におよ… [Typhoon No. 13 (Dolphin) has formed]”

official JMA formation announcementread the original ↗

Japan

WeatherNews

“発達して8月1日には南鳥島近海で猛烈な勢力となる予想。[Forecast to reach violent intensity near Minami-Torishima by August 1]”

private Japanese forecaster, track and intensityread the original ↗

Hong Kong

Dim Sum Daily

“Tropical Storm Dolphin, named by Hong Kong after the Chinese white dolphin, formed on 27th July in the central Pacific and is expected by regional agencies to strengthen to super-typhoon intensity.”

Hong Kong regional perspective, HK named the stormread the original ↗

post

Summary

Japan's 2026 typhoon season produced its 13th storm on July 27 when the Japan Meteorological Agency upgraded a tropical depression to Typhoon Dolphin at 13.3°N, 176.9°E in the central Pacific. The JMA forecasts the storm will intensify rapidly, reaching violent strength by August 1 near Minami-Torishima (Marcus Island, Japan). As of July 28 it is in the Marshall Islands region, moving west-southwest at 25 km/h through sea-surface temperatures above 30°C that will sustain development. Hong Kong named the storm Dolphin after the Chinese white dolphin. Forecast models from the JMA, the US Joint Typhoon Warning Center, and Europe's ECMWF diverge sharply on whether Dolphin tracks into Japan's main islands; private forecasters are careful not to rule it out during the Obon holiday travel window in mid-August.

The split

Japanese public forecasters (NHK, WeatherNews, Tenki.jp) emphasise the risk to Obon travellers and the storm's rapid-intensification potential, urging early preparation. International models (JTWC, ECMWF) remain in dispute on the northward turn that would send Dolphin toward Japan; News on Japan notes that "forecasts remain sharply divided." Dim Sum Daily highlights Hong Kong's naming authority and the storm's category, consistent with the city's focus on Pacific maritime risk.

By the numbers

  • 13, typhoon number in Japan's 2026 season
  • 75 m/s, maximum wind gusts forecast by the JMA at peak intensity
  • 25 km/h, current movement speed in the Marshall Islands region as of July 28
  • August 1, forecast date for Dolphin reaching violent super-typhoon intensity
  • 30°C+, sea-surface temperatures along the projected track, supporting rapid development

Why it matters

If Dolphin tracks toward Japan's main islands, it would arrive during the Obon holiday period (mid-August), Japan's peak domestic travel season, potentially disrupting transport and causing evacuation orders for coastal and mountainous prefectures. Japan is already tracking Typhoon Noul's aftermath in China; a second major Pacific storm in the same week indicates a hyperactive late-July Pacific typhoon season.

What to watch

  • Whether the JMA, JTWC and ECMWF models converge on a northward track toward Japan in the next 48-72 hours.
  • Speed of intensification through the Marshall Islands and near Minami-Torishima: a faster-than-forecast intensification raises the risk of a Category 5-equivalent landfall.
  • Japan government activation of early-warning guidance for Obon travel, which would signal official confidence in a Japan approach.

The briefing, by email