Tag Archives: Pago Pago

Tropical Cyclone Nat Moves Toward Tahiti

Tropical Cyclone Nat moved toward Tahiti on Tuesday. At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone Nat was located at latitude 17.6°S and longitude 155.4°W which put it about 415 miles (670 km) west of Pappete, Tahiti. Nat was moving toward the east-southeast at 20 m.p.h. (32 km/h). The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h). The minimum surface pressure was 993 mb.

Tropical Cyclone Nat strengthened a little as it moved over the South Pacific Ocean toward Tahiti on Tuesday. Thunderstorms continued to form near the center of Nat’s circulation. Storms near the center of circulation generated upper level divergence that pumped mass away to the east of the tropical cyclone. Thunderstorms were also occurring in bands in the northern and eastern parts of Tropical Cyclone Nat. Bands in the western and southern part of Nat’s circulation consisted primarily of showers and lower clouds. Winds to tropical storm force extend out 120 miles (195 km) in the northwest, northeast and southeast quadrants of Tropical Cyclone Nat. Winds to tropical storm force only extended out 40 miles (65 km) in the southwest quadrant of Nat.

Tropical Cyclone Nat will move through an environment unfavorable for intensification during the next 24 hours. Nat will move over water where the Sea Surface Temperatures are near 29°C. It will move under the eastern side of an upper level trough over the South Pacific Ocean northeast of New Zealand. The upper level trough will produce strong northwesterly winds that will blow toward the top of Nat’s circulation. Those winds will cause strong vertical wind shear. The strong vertical wind shear is likely to cause Tropical Cyclone Nat to start to weaken during the next 24 hours.

The upper level trough northeast of New Zealand will steer Tropical Cyclone Nat toward the east-southeast during the next 24 hours. On its anticipated track, the center of Tropical Cyclone Nat will pass south of Bora Bora during the next 24 hours. Nat could be near Tahiti within 36 hours. Bands in the northern side of Nat could bring gusty winds and locally heavy rain to the Society Islands. Heavy rain could cause flash floods in some locations.

Elsewhere over the South Pacific Ocean, Tropical Cyclone 11P formed north of American Samoa. At 4:00 p.m. EST on Tuesday the center of Tropical Cyclone 11P was located at latitude 13.3°S and longitude 168.9°W which put it about 110 miles (195 km) north of Pago Pago, American Samoa. The tropical cyclone was moving toward the southeast at 21 m.p.h. (33 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 997 mb. Heavy rain could cause flash floods in parts of American Samoa.

Tropical Cyclone Wasi Brings Wind and Rain to Samoa

Tropical Cyclone Wasi brought wind and rain to Samoa  on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Wasi was located at latitude 16.7°S and longitude 171.3°W which put it about 140 miles (225 km) south-southwest of Pago Pago, American Samoa.  Wasi was moving toward the south-southeast at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 996 mb.

The eastern side of Tropical Cyclone Wasi brought wind and rain to parts of Samoa on Saturday.  A weather station in Pago Pago, American Samoa reported a sustained wind speed of 25 m.p.h. (40 km/h) and a wind gust of 43 m.p.h. (69 km/h).  Several inches of rain also fell on parts of Samoa.

Tropical Cyclone Wasi moved under the western side of an upper level ridge over the South Pacific Ocean.  The ridge produce strong northerly winds which blew across the top of Wasi.  Those winds caused strong vertical wind shear and Tropical Cyclone Wasi began to weaken.  Many of the taller thunderstorms dissipated.  Some storms were still occurring in a band south and east of the center of circulation.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out 75 miles (120 km) from the center of Wasi.

Tropical Cyclone Wasi will move through an environment unfavorable for intensification.  Wasi will move over water where the Sea Surface Temperature is near 28°C.  However, the upper level ridge will continue to cause strong vertical wind shear.  The shear will be strong enough to prevent significant intensification and Tropical Cyclone Wasi could continue to weaken since it has a small circulation.

Tropical Cyclone Wasi will move around the western end of a high pressure system over the South Pacific Ocean.  The high will steer Wasi toward the south.  On its anticipated track Tropical Cyclone Wasi could pass near Niue in about 18 hours.  Wasi will bring gustier winds and rain showers to Niue on Sunday.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vicky was dissipating south of Niue.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Vicky was located at latitude 22.6°S and longitude 168.6°W which put it about 250 miles (400 km) south-southeast of Niue.  Vicky was moving toward the south at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1004 mb.

Tropical Cyclone Wasi Develops Near Samoa

Tropical Cyclone Wasi developed near Samoa on Friday night.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Wasi was located at latitude 13.6°S and longitude 172.9°W which put it about 20 miles (35 km) west of Falealupo, Samoa and about 185 miles (300 km) west-northwest of Pago Pago, American Samoa.  Wasi was moving toward the southeast at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 993 mb.

Tropical Cyclone Wasi spun up out of the same elongated trough of low pressure near Samoa that produced Tropical Cyclone Vicky on Thursday.  A small center of low pressure developed west-northwest of Samoa on Friday.  More thunderstorms formed near the center of circulation and the system was classified as Tropical Cyclone Wasi.  Microwave satellite imagery indicated that there was a tight inner core in the tropical cyclone.  Storms near the core were generating upper level divergence which was pumping mass away from Tropical Cyclone Wasi.  The circulation around Wasi was even smaller than the circulation around Tropical Cyclone Vicky.  Winds to tropical storm force only extended out about 50 miles (80 km) from the center of Tropical Cyclone Wasi.

Tropical Cyclone Wasi will move into an environment somewhat favorable for intensification during the next 24 to 36 hours.  Wasi will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western end of an upper level ridge over the South Pacific Ocean.  The ridge will produce northwesterly winds which will blow toward the top of the tropical cyclone.  Those winds will cause moderate vertical wind shear, but the winds may not be strong enough to prevent intensification.  Tropical Cyclone Wasi could strengthen during the next 24 to 36 hours.  Since the circulation around Wasi is so small, if the tropical cyclone moves into an area where the upper level winds are stronger, it could weaken quickly.

Tropical Cyclone Wasi will move around the western end of a high pressure system over the South Pacific Ocean.  The high will steer Wasi toward the southeast during the next 12 hours.  Wasi will move more toward the south later in the weekend.  On its anticipated track Tropical Cyclone Wasi will bring gust winds and locally heavy rain to portions of Samoa during the next 24 hours.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vicky weakened as it passed near Niue on Friday.  At 10:00 p.m. EST on Friday the center of Tropical Cyclone Vicky was located at latitude 19.7°S and longitude 168.7°W which put oit about 95 miles (150 km) southeast of Niue.  Vicky was moving toward the south-southeast at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1001 mb.

Tropical Cyclone Vicky Forms Near Samoa

Tropical Cyclone Vicky formed near Samoa on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Vicky was located at latitude 15.2°S and longitude 170.6°W which put it about 35 miles (55 km) south of Pago Pago, American Samoa.  Vicky was moving toward the southeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 992 mb.

A small low pressure system developed quickly within a large elongated trough extending east-southeast across Samoa on Thursday.  A small well defined circulation was evident on satellite imagery.  Thunderstorms developed near the center of the low pressure system and it was designated as Tropical Cyclone Vicky.  Storms near the center began to generate upper level divergence which pumped mass away from the tropical cyclone.  Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.  A weather station at Pago Pago reported a sustained wind speed of 43 m.p.h. (69 km/h) and a wind gust of 75 m.p.h. (120 km/h) when the developing tropical cyclone passed nearby.

Tropical Cyclone Vicky will move through an environment only marginally favorable for intensification during the next several days.  Vicky will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western side of an upper level ridge over the South Pacific Ocean that extends southeast of Samoa.  The ridge will produce strong northwest winds which will cause moderate to strong vertical wind shear.  The wind shear will inhibit intensification and could cause Tropical Cyclone Vicky to weaken.  Since the circulation around Vicky is small, it could weaken rapidly if the wind shear increases.

Tropical Cyclone Vicky will move around the western side of a high pressure system over the South Pacific Ocean southeast of Samoa.  The ridge will steer Vicky toward the south during the next 24 to 48 hours.  On its anticipated track Tropical Cyclone Vicky could approach Niue in about 48 hours.  Vicky could be the equivalent of a tropical storm when it approaches Niue.

Tropical Cyclone Gita Forms Near Samoa

Tropical Cyclone Gita formed near Samoa on Friday.  At 10:00 a.m. EST on Friday the center of Tropical Cyclone Gita was located at latitude 14.8°N and longitude 172.3°E which put it about 155 miles (250 km) west of Pago Pago, Samoa.  Gita was moving toward the east at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 989 mb.

Tropical Cyclone Gita was bringing gusty winds and heavy rain to Samoa.  The strongest rainbands were north and east of the center of circulation.  The bands south of the center consisted primarily of showers and low clouds.  There appeared to be drier air in the southern half of the circulation which was inhibiting the development of taller clouds and stronger storms in that part of Gita.  Thunderstorms in the rainbands north of the center of circulation were generating upper level divergence which was pumping mass away to the east of the tropical cyclone.

Tropical Cyclone Gita will be moving through an environment favorable for intensification.  Gita will move over water where the Sea Surface Temperature is near 30°C.  An upper level low south of Gita is producing easterly winds which are blowing toward the top of the circulation.  Those winds are causing some vertical wind shear, but the shear does not appear to be strong enough to prevent intensification.  The drier air in southern half of the circulation will inhibit intensification.  However, if some of the rainbands north of the center wrap around the southern side of the center, then they could reduce the effects of the drier air.  Tropical Cyclone Gita is likely to intensify into the equivalent of a hurricane/typhoon during the weekend.

The upper low south of Gita is currently steering the tropical cyclone toward the east.  Gita will approach the eastern end of the upper low during the next 24 hours and it will move more toward the south.  Tropical cyclone Gita will turn back toward the west when it moves south of the upper low.  On its anticipated track Tropical Cyclone Gita will continue to bring gusty winds and heavy rain to Samoa for another 12 to 24 hours.  Gita could pass near Niue in 24 to 48 hours and it could move near Tonga in about three days.