Tropical Storm Halola to Affect Western Japan After Passing Near Okinawa (FORECAST)

Nick Wiltgen
Published: July 25,2015
Tropical Storm Halola is now impacting the Ryukyu Islands of southern Japan, including Okinawa and Amami.
The center of Halola made its closest approach to Okinawa during the day Saturday, local time, passing east and northeast of that island. (Japan is 13 hours ahead of U.S. Eastern Daylight Time.)

Typhoon Halola: Current Status and Infrared Satellite

As of 10 p.m. Japan Standard Time (JST) Saturday, Halola was centered about 25 miles (40 kilometers) west of the city of Amami and moving to the north-northwest at 12 mph, according to the Japan Meteorological Agency. JMA downgraded Halola from a typhoon to a tropical storm in its 7 p.m. JST bulletin, analyzing its maximum sustained winds at 70 mph (30 meters per second) since then.
The U.S. military's Joint Typhoon Warning Center downgraded Halola to a tropical storm Saturday afternoon, also giving it maximum sustained winds of 70 mph.
Halola is expected to slowly weaken as it moves north through the Amami Islands Saturday night, and appears to be passing directly over the largest of them, Amami Ōshima.
Tropical storm-force sustained winds have been reported already at the Amami Airport, where sustained winds reached 64.9 mph (29.0 meters per second) at 10:44 p.m. local time Saturday. Around the same time, the airport gusted to 79.4 mph (35.5 meters per second). Tropical storm-force winds have also been measured just to the north of Okinawa on the islands of Okinoerabu and Tokunoshima, where sustained winds of at least 20 meters per second (44 mph) have been clocked.
Early Saturday morning, when Halola was still a typhoon, the island of Minamidaitō reported a sustained wind of 70.9 mph (31.7 meters per second). That is the highest sustained wind reported on land due to Halola. The same island reported a peak gust of 97.8 mph (43.7 meters per second).
Sustained winds of tropical storm-force on Okinawa itself are no longer expected, though some parts of Okinawa did come close with sustained winds up to around 35 mph.
Kadena Air Base, Okinawa, was placed in tropical cyclone condition of readiness (TCCOR) 1 Friday evening, meaning damaging winds of 50 knots (58 mph) or more were expected within 12 hours. As Halola turned north earlier than predicted, Kadena shifted to TCCOR Storm Watch Saturday afternoon, and then lowered to TCCOR 4, the default level during the peak of typhoon season, Saturday evening.
The peak sustained wind at Kadena was 31 mph Saturday afternoon, and the peak gust was 42 mph. Almost 18,000 Americans and another 4,000 Japenese employees are stationed at Kadena.
(FORECAST: Okinawa)
The Japanese Meteorological Agency has issued warnings and advisories for high waves generated from Halola, particularly on south and east-facing shores of the Ryukyu Islands and southern parts of Kyushu, the southwesternmost of Japan's four main islands.

Halola Forecast

Halola will continue to move north and pass near or west of the Japanese mainland later in the weekend, potentially passing close to the coast of South Korea.
Halola is also expected to succumb to wind shear – typical for tropical cyclones moving northward near mainland Japan – leading to weakening during this time.
In an ironic twist, the tropical cyclone has actually improved the weather over parts of Japan in the last couple of days.
That's because it was extremely rainy earlier this week in western parts of the mainland as well as the Ryukyu island chain, which includes Okinawa, south of the mainland. A persistent fetch of moisture-laden southwesterly winds, unrelated to the typhoon, dumped torrential rainfall on those areas.
The Japan Meteorological Agency says more than 600 millimeters (24 inches) of rain fell in 48 hours Monday and Tuesday on Nakanoshima, a small volcanic island in that chain. The village of Sata near the southern tip of Kyushu tallied 545.5 millimeters (21.48 inches) of rain in 72 hours Monday through Wednesday, with rain falling at a ferocious rate of 85 millimeters (3.35 inches) per hour at one point.
Interestingly, the wind circulation from Halola helped to disrupt that fetch of soggy air and replaced it with drier air on the outer periphery of Halola's core.
(MORE: More Than 6,000 Hospitalized In Japanese Heat Wave)
That said, inside Halola's core there is still plenty of moisture, and some of that is being wrung out over the Ryukyu Islands. In particular, JMA's automated observation site at Isen, on the island of Tokunoshima, reported 114.5 millimeters (4.51 inches) of rain in one hour and 258.5 millimeters (10.18 inches) in three hours Saturday evening, both setting all-time records since that location began keeping weather records in 1977. The storm total rainfall there reached 338 millimeters (13.31 inches) as of 11 p.m. JST Saturday. About 7,500 people on the island have been advised to evacuate, according to Japan's public broadcaster, NHK.
Most other areas being affected by Halola have reported less than half of those rainfall amounts, however.
All told, the large-scale impacts of Halola may end up being rather insignificant compared to the wet weather pattern it replaced. Japan is well prepared for strong winds from tropical cyclones, especially those below typhoon strength – and Halola's rains are likely to pale in comparison to this week's rains or those from last week's Typhoon Nangka.

Rainfall Forecast

While we never want to write off a tropical cyclone as harmless, it's entirely plausible that Halola could end up being a bizarre case of a tropical cyclone making the weather better for some people rather than worse.
Stay with The Weather Channel, weather.com and Weather Underground as we continue to follow Typhoon Halola.
Meteorologists Chris Dolce and Jonathan Erdman contributed to this report.
MORE: Typhoon Nangka, July 16-17, 2015