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Typhoon Phanfone Aims at Tokyo; Typhoon Vongfong Belting Guam

By: Dr. Jeff Masters, 1:38 PM GMT on October 05, 2014

Typhoon Phanfone is weakening as is races northeastward towards the main Japanese island of Kyushu. Japanese radar showed that heavy rains from Phanfone were affecting most of the main Japanese islands of Kyushu and Honshu on Sunday morning, and satellite loops showed that Phanfone remained intact in the face of wind shear in excess of 30 knots, with a large area of heavy thunderstorms and a prominent eye. Phanfone will make its closest pass by Tokyo near 01 UTC Monday (9 pm EDT Sunday.) High wind shear and cooler waters will continue to weaken Phanfone, and it should be no stronger than a Category 1 storm at its point of closest approach to Tokyo. Heavy rains from Phanfone are the main threat, and are likely to bring dangerous flash flooding and mudslides.

According to TWC's Nick Wiltgen, Tokyo has a pretty high threshold for record rainfall. In data going back to 1886, the top ten one-hour rainfalls are all at least 69.2 mm (2.72 inches), and the calendar-day rainfall record rainfall since 1875 is 371.9 mm (14.64 inches). The top sustained wind on record since 1875 is 31.0 m/s or 69.3 mph, and a mere 22.6 m/s (50.6 mph) wind from Phanfone would give Tokyo an all-time top-10 sustained wind. The highest wind gust on record for central Tokyo is 46.7 m/s (104.5 mph) which, like the sustained wind record, was set September 1, 1938.

Figure 1. Radar image of Typhoon Phanfone taken at 22:15 JST (9:15 am EDT) Sunday, October 5, 2014 from the Japan Meteorological Agency.

Typhoon warnings in Guam for Category 2 Vongfong
Typhoon warnings are flying for the U.S. Northern Mariana islands of Guam, Rota, Saipan, and Tinian as intensifying Category 2 Typhoon Vongfong plows west-northwest at 24 mph through the islands. The island of Rota, about 25 miles north of Guam, is expected to receive the worst beating. The eye of Vongfong is on track to pass just to the north of Rota, as seen on radar out of Guam. The NWS is warning that Rota could see sustained winds of 90 - 110 mph, which will cause extensive damage. A storm surge of 3 - 5 feet and rains of 5 - 8 inches are also expected. As of 9 am EDT Sunday (11 pm local time), winds had begun to rise sharply at Andersen AFB on the north end of Guam, with a peak gust of 33 mph. The typhoon is expected to turn more to the northwest later in the week, and could be a threat to Japan in 6 - 8 days.

Figure 2. Radar out of Guam of Typhoon Vongfong, taken at 9:29 am EDT Sunday. The radar cannot "see" all of Rota due to blockage of the radar beam by mountains.

Simon says: I'm a major hurricane!
In the Eastern Pacific, Hurricane Simon put on an impressive burst of rapid intensification Saturday, topping out as a Category 4 hurricane with 135 mph winds at 11 pm EDT Saturday. Simon is the eighth intense hurricane so far in the Eastern Pacific (east of 140°W), putting this year in a tie with 1992 for the highest number of of major hurricanes in one season. The 2014 Eastern Pacific hurricane season tally now stands at 18 named storms, 13 hurricanes, and 8 intense hurricanes. An average Eastern Pacific hurricane season sees just 15 named storms, 8 hurricanes, and 3 intense hurricanes during the entire year, with two of those named storms and one hurricane occurring after October 10. Simon is expected to recurve to the northeast, and bring rains of 2 - 4" to the central coast of Mexico's Baja Peninsula as it dissipates near landfall on Tuesday. Deep moisture from Simon will flow northeastward across Mainland Mexico and into the Southwest U.S. this week, and the 00Z Sunday runs of the GFS and European models are in agreement that heavy rainfall from Simon's moisture will begin to affect the Southwest U.S. on Wednesday.

Figure 3. MODIS satellite image of Hurricane Simon taken at approximately 6 pm EDT October 4, 2014. At the time, Simon was a Category 3 storm with 120 mph winds and was undergoing rapid intensification that would take it to a Category 4 storm with 135 mph winds by 11 pm EDT. Image credit: NASA.

Quiet in the Atlantic
Our top three models for predicting tropical cyclone genesis show nothing developing over the next five days in the Atlantic, though the GFS model predicts the waters in the Southwest Caribbean off the coast of Costa Rica could spawn a large area of low pressure capable of developing into a tropical depression next weekend.

Jeff Masters


The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.