Noul Intensified Into a Typhoon As It Passed Over Yap

Tropical Storm Noul intensified slowly on Tuesday and it attained typhoon status as it passed over Yap.  At 10:00 p.m. EDT on Tuesday the center of Typhoon Noul was located at latitude 9.5°N and longitude 137.5°E which put it about 20 miles west-southwest of Yap and about 230 miles east-northeast of Palau.  Noul was moving toward the west at 5 m.p.h.  The maximum sustained wind speed was 75 m.p.h. and there were gusts to 90 m.p.h.  The minimum surface pressure was 976 mb.  Noul brought wind and heavy rain to Yap on Tuesday.  The International Airport reported a wind gust of 68 m.p.h. as the center of Noul passed just south of it.

An upper level ridge located east of the center of circulation is causing light easterly winds to blow over the top of Noul, which is generating some vertical wind shear.  The shear could be the reason why most of the strongest thunderstorms are occurring in the southwestern quadrant of the circulation.  Noul remains over water where the Sea Surface Temperature is around 29°C.  The vertical wind shear is likely to slow the rate of intensification, but Noul is in an environment that favors further strengthening.

Noul is at the western end of a subtropical ridge and the steering pattern is relatively weak.  It is likely to continue to move slowly for another 12 to 24 hours.  Eventually a subtropical ridge is expected to build north of Noul and steering it toward the west-northwest at a faster speed.  On its projected path the center of Noul would pass several hundred miles north of Palau.  Noul could be approaching the northern Philippines by late in the week.