Tag Archives: New Zealand

Tropical Cyclone Tam Develops East of New Caledonia

Tropical Cyclone Tam developed over the South Pacific Ocean east of New Caledonia on Tuesday.  At 5:00 a.m. EDT on Tuesday the center of Tropical Cyclone Tam was located at latitude 21.9°S and longitude 171.4°E which put the center about 335 miles (540 km) east of Noumea, New Caledonia.  Tam was moving toward the southeast at 25 m.p.h. (40 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 988 mb.

A low pressure system over the South Pacific Ocean east of New Caledonia strengthened during Monday night and the Fiji Meteorological Service designated the system as Tropical Cyclone Tam.

The distribution of thunderstorms around Tropical Cyclone Tam was asymmetrical.  Tam was located under the eastern side of an upper level trough that was east of Australia.  The upper level trough was producing strong northwesterly winds that were blowing toward the top of Tam’s circulation.  Those winds were causing strong vertical wind shear.  The strong wind shear was causing the asymmetrical distribution of thunderstorms in Tropical Cyclone Tam.  Thunderstorms were occurring in bands in the southern and eastern parts of Tam’s circulation.  Bands in the northern and western parts of Tropical Cyclone Tam consisted primarily of showers and lower clouds.

The asymmetrical distribution of thunderstorms was also causing the distribution of wind speeds to be asymmetrical.  Winds to tropical storm force extended out 250 miles (400 km) in the eastern side of Tropical Cyclone Tam.  The winds in the western half of Tam’s circulation were blowing at less than tropical storm force.

Tropical Cyclone Tam will move into an environment that will be unfavorable for the intensification of a tropical cyclone during the next 24 hours.  Tam will move over water where where the Sea Surface Temperatures are near 24°C.  The upper level trough east of Australia will continue to cause strong vertical wind shear.  The combination of cool Sea Surface Temperatures and strong vertical wind shear will cause Tropical Cyclone Tam to make a transition to a strong extratropical cyclone during the next 24 hours.

The upper level trough east of Australia will steer Tropical Cyclone Tam toward the south during the next 24 hours.  On its anticipated track, Tam will move quickly away from New Caledonia.  Tropical Cyclone Tam will move closer to northern New Zealand.

Tropical Cyclone Gabrielle Transitions to an Extratropical Cyclone

Former Tropical Cyclone Gabrielle made a transition to an extratropical cyclone northwest of New Zealand on Friday. At 4:00 p.m. EST on Friday the center of former Tropical Cyclone Gabrielle was located at latitude 27.2°S and longitude 165.3°E which put it about 670 miles (1080 km) northwest of Auckland, New Zealand. Gabrielle was moving toward the southeast at 29 m.p.h. (46 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h). The minimum surface pressure was 979 mb.

Former Tropical Cyclone Gabrielle made a transition to an extratropical cyclone on Friday. Gabrielle moved over water where the Sea Surface Temperatures are near 24˚C. An upper level trough east of Australia produced northwesterly winds that blew toward the top of Gabrielle’s circulation. Those winds cause strong vertical wind shear. A combination of cooler water and strong vertical wind shear caused former Tropical Cyclone Gabrielle to make a transition to a strong extratropical cyclone. Strong thunderstorms were still occurring in bands in the southern half of the extratropical cyclone. Bands in the northern half of the circulation consisted primarily of showers and lower clouds. The transition to an extratropical cyclone caused the size of the low pressure system to expand. Winds to tropical storm force extended out 330 miles (530 km) from the center of circulation.

The upper level trough east of Australia will steer the extratropical cyclone quickly toward the southeast. On its anticipated track, former Tropical Cyclone Gabrielle could affect northern New Zealand during the weekend. The extratropical cyclone will bring strong winds and locally heavy rain to northern New Zealand. Heavy rain could cause flash floods in some locations.

Tropical Cyclone Gabrielle Intensifies to Equivalent of a Hurricane/Typhoon

Tropical Cyclone Gabrielle intensified to the equivalent of a hurricane/typhoon over the Coral Sea on Thursday morning. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Gabrielle was located at latitude 20.1°S and longitude 155.6°E which put it about 565 miles (910 km) north-northeast of Brisbane, Australia. Gabrielle was moving toward the southeast at 13 m.p.h. (20 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 971 mb.

Tropical Cyclone Gabrielle intensified over the Coral Sea on Thursday morning. The inner end of a rainband wrapped around the center of Gabrielle’s circulation. A small eye appeared to be forming at the center of circulation. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Gabrielle. Storms near the core generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Gabrielle’s circulation. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation.

Tropical Cyclone Gabrielle will move through an environment favorable for intensification during the next 24 hours. Gabrielle will move over over water where the Sea Surface Temperatures are near 27˚C. An upper level trough near the east coast of Australia will produce northwesterly winds that will blow toward the top of Gabrielle’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification. Tropical Cyclone Gabrielle is likely to intensify during the next 24 hours.

The upper level trough near the east coast of Australia will steer Tropical Cyclone Gabrielle toward the southeast during the next 48 hours. On its anticipated track Gabrielle will move between Australia and New Caledonia. Bands in the eastern side of Tropical Cyclone Gabrielle could bring gusty winds and locally heavy rain to New Caledonia. Gabrielle will move over cooler water during the weekend and the vertical wind shear will increase. Cooler water and more wind shear will cause Tropical Cyclone Gabrielle to make a transition to an extratropical cyclone. Gabrielle could affect northern New Zealand as a strong extratropical cyclone in a few days.

Tropical Cyclone Dovi Moves Toward New Zealand

Tropical Cyclone Dovi moved toward New Zealand on Friday morning. At 10:00 a.m. EST on Friday the center of Tropical Cyclone Dovi was located at latitude 30.0°S and longitude 166.3°E which put it about 780 miles (1200 km) northwest of Auckland, New Zealand. Dovi was moving toward the south at 24 m.p.h. (39 km/h). The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 969 mb.

Tropical Cyclone Dovi was located between New Caledonia and New Zealand on Friday morning. There was an eye with a diameter of 25 miles (40 km) at the center of Dovi’s circulation. The eye was surrounded by a broken ring of thunderstorms. The strongest thunderstorms were occurring in the eastern half of the ring. There were breaks in the northwestern part of the ring of storms. Bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Dovi. Storms near the core generated upper level divergence that pumped mass away to the southeast of the tropical cyclone. Winds to hurricane/typhoon force extended out 50 miles (80 km) from the center of Dovi. Winds to tropical storm force extended out 250 miles (400 km) from the center of circulation.

Tropical Cyclone Dovi will move into an environment that is unfavorable for a tropical cyclone. Dovi will move over water where the Sea Surface Temperatures are near 23˚C. An upper level trough centered east of Australia will produce strong northwesterly winds that will blow toward the top of Dovi’s circulation. Those winds will cause strong vertical wind shear. The combination of colder water and strong vertical wind shear will cause Tropical Cyclone Dovi to make a transition to a strong extratropical cyclone.

The upper level trough east of Australia will steer Tropical Cyclone Dovi toward the southeast during the next 36 hours. On its anticipated track Dovi will move across New Zealand during the weekend. Tropical Cyclone Dovi will be a strong extratropical cyclone when it crosses New Zealand. Dovi will bring strong winds and locally heavy rain to parts of New Zealand. The strongest winds and heaviest rain will occur in northern New Zealand.

Tropical Cyclone Dovi Intensifies to Equivalent of Hurricane/Typhoon

Tropical Cyclone Dovi intensified to the equivalent of a hurricane/typhoon near the southern end of New Caledonia on Thursday morning. At 10:00 a.m. EST on Thursday the center of Tropical Cyclone Dovi was located at latitude 23.6°S and longitude 166.7°E which put it about 80 miles (130 km) southeast of Noumea, New Caledonia. Dovi was moving toward the southwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 969 mb.

Tropical Cyclone Dovi strengthened to the equivalent of a hurricane/typhoon near the southern end of New Caledonia on Thursday morning. An eye with a diameter of 50 miles (80 km) formed at the center of Dovi’s circulation. The eye of Tropical Cyclone Dovi passed over the Ile des Pins. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the center of Dovi’s circulation. Winds to hurricane/typhoon force extended out 25 miles (40 km) to the east of the center of Tropical Cyclone Dovi. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation.

Tropical Cyclone Dovi will move around the western end of a high pressure system over the South Pacific Ocean. The high pressure system will steer Dovi toward the south during the next several days. On its anticipated track Tropical Cyclone Dovi will move away from southern New Caledonia. Dovi will continue to cause strong winds and locally heavy rain over southern New Caledonia during the next few hours. Locally heavy rain could cause flash floods in some locations. Weather conditions should improve in New Caledonia when Tropical Cyclone Dovi moves farther away. Dovi could approach New Zealand during the weekend as a strong extratropical cyclone.

Tropical Cyclone Dovi will move through an environment favorable for intensification during the next 12 hours. Dovi will move over water where the Sea Surface Temperatures are near 28˚C. It will move under the western part of an upper level ridge centered east of New Caledonia. The ridge will produce southerly winds that will blow toward the top of the tropical cyclone. Those winds will cause some vertical wind shear. The wind shear will inhibit intensification, but it will not be strong enough to prevent intensification. Tropical Cyclone Dovi is likely to intensify during the next 12 hours. Dovi will move into a region where the Sea Surface Temperatures are colder and where there will be more vertical wind shear during the weekend. The combination of colder water and more wind shear will cause Tropical Cyclone Dovi to make a transition to a strong extratropical cyclone.

Tropical Cyclone Ruby Brings Wind and Rain to New Caledonia

Tropical Cyclone Ruby brought wind and rain to New Caledonia on Monday night. At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Ruby was located at latitude 22.6°S and longitude 168.3°E which put it about 85 miles (135 km) east of Noumea, New Caledonia. Ruby was moving toward the east-southeast at 22 m.p.h. (35 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 994 mb.

Tropical Cyclone Ruby brought wind and rain to much of New Caledonia on Monday night. The center of Ruby made landfall on the northwest end of New Caledonia near Poum. Tropical Cyclone Ruby moved quickly toward the southeast and the center of circulation passed over most of the entire length of New Caledonia. The center exited the coast east of Noumea on Tuesday morning. Winds to tropical storm force extended out 60 miles in the northern half of Ruby’s circulation. So, Tropical Cyclone Ruby brought tropical storm force winds to much of New Caledonia. The winds in the southern half of Ruby’s circulation were blowing at less than tropical storm force. Tropical Cyclone Ruby also dropped locally heavy rain over parts of New Caledonia. Clockwise rotation around Ruby would have caused the air to flow up the eastern slopes of mountains and the heaviest rain likely occurred in those areas. Locally heavy rain may have caused flash floods in some places.

An upper level trough east of Australia will steer Tropical Cyclone Ruby quickly toward the southeast during the next 36 hours. On its anticipated track Ruby will be northeast of New Zealand in 36 hours. The upper level trough will produce strong northwesterly winds that will blow toward the top of Ruby’s circulation. Those winds will produce moderate vertical wind shear. Tropical Cyclone Ruby will move over much cooler water when it moves toward the southeast. The combination of moderate vertical wind shear and cooler water will cause Tropical Cyclone Ruby to make a transition to an extratropical cyclone during the next 36 hours.

Tropical Cyclone Yasa Passes West of Tonga

Tropical Cyclone Tonga passed west of Tonga on Friday. At 4:00 p.m. EST on Friday the center of Tropical Cyclone Yasa was located at latitude 20.6°S and longitude 178.0°W which put it about 280 miles (305 km) west of Nuku’Alofa, Tonga. Yasa was moving toward the south at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h). The minimum surface pressure was 974 mb.

After making a direct hit on Vanua Levu, Tropical Cyclone Yasa moved over the Fiji islands in the Lau Group. There were reports of damage and casualties from Fiji. Tropical Cyclone Yasa weakened after it made landfall on Vanua Levu. The eye and eyewall were disrupted by passage over land. An upper level low centered north of New Zealand produced northerly winds which blew toward the top of Yasa’s circulation on Friday. Those winds caused moderate vertical wind shear and the shear caused the tropical cyclone to weaken steadily on Friday.

The circulation around Tropical Cyclone Yasa exhibited less organization on Friday. The strongest thunderstorms were occurring in a band in the southern half of the circulation. Bands in the northern half of Yasa consisted primarily of showers and lower clouds. The circulation around Tropical Cyclone Yasa was still large. Winds to tropical storm force extended out 200 miles (320 km) from the center of circulation.

Tropical Cyclone Yasa will move through an environment that is mostly unfavorable for intensification during the next several days. Yasa will move over water where the Sea Surface Temperature is near 27°C. However, the upper level low centered north of New Zealand will continue to cause moderate vertical wind shear. The shear is likely to be strong enough to cause Tropical Cyclone Yasa to continue to weaken.

Tropical Cyclone Yasa will move around the eastern side of the upper level low. The low will steer Yasa toward the southwest during the next 48 hours. On its anticipated track Tropical Cyclone Yasa will pass west of Tonga and it will remain north of New Zealand.

Tropical Cyclone Gretel Speeds By New Caledonia

Tropical Cyclone Gretel sped by New Caledonia on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Cyclone Gretel was located at latitude 25.9°S and longitude 169.4°E which put it about 750 miles (1210 km) north-northwest of Auckland, New Zealand.  Gretel was moving toward the southeast at 37 m.p.h. (60 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 983 mb.

Tropical Cyclone Gretel moved around the western end of high pressure system over the South Pacific Ocean.  The high steered Gretel rapidly toward the southeast and the tropical cyclone sped over the Coral Sea west of New Caledonia.  Rainbands on the eastern side of Tropical Cyclone Gretel brought wind and rain to portions of New Caledonia on Sunday.

An upper level ridge produced strong northwesterly winds which created strong vertical wind shear.  The wind shear tilted the circulation around Tropical Cyclone Gretel toward the southeast and Gretel began to weaken.  The stronger thunderstorms were occurring in bands south and east of the center of Gretel.  Bands in other parts of the tropical cyclone consisted primarily of showers and lower clouds.  The wind field around Gretel expanded when the tropical cyclone started to weaken.  Winds to tropical storm force extended out 250 miles (400 km) from the center of circulation.

Tropical Cyclone Gretel will continue to move rapidly toward the southeast during the next several days.  On its anticipated track Gretel could pass north of New Zealand in 24 to 36 hours.

Elsewhere, over the South Indian Ocean Tropical Cyclone Herold strengthened east of Madagascar.  At 5:00 p.m EDT on Sunday the center of Tropical Cyclone Herold was located at latitude 15.5°S and longitude 53.2°E which put it about 405 miles (655 km) west-northwest of Port Louis, Mauritius.  Herold was moving toward the east-southeast at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 972 mb.  Tropical Cyclone Herold could reach Rodrigues in about 48 hours.

Tropical Cyclone Oma Strengthens Northwest of New Caledonia

Tropical Cyclone Oma strengthened over the Coral Sea northwest of New Caledonia on Monday.  At 10:00 p.m. EST on Monday the center of Tropical Cyclone Oma was located at latitude 19.9°S and longitude 162.1°E which put it about 295 miles (475 km) west-northwest of Noumea, New Caldonia.  Oma was moving toward the south-southwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 966 mb.

The circulation around Tropical Cyclone Oma strengthened on Monday.  A broken ring of thunderstorms developed around a large eye at the center of circulation.  The eye had a diameter of approximately 60 miles (95 km).  The strongest winds were occurring in the parts of the ring with active thunderstorms.  Bands of showers and thunderstorms were revolving around the large inner core of Tropical Cyclone Oma.  Storms near the core were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to hurricane/typhoon force extended out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out about 200 miles (320 km) from the center.

Tropical Cyclone Oma will be moving through an environment favorable for intensification during the next 24 to 36 hours.  Oma will move over water where the Sea Surface Temperature is near 28.5°C.  It will move through an area where the upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Oma is likely to intensify during the next day or so.

Tropical Cyclone Oma will move around the western end of a subtropical ridge over the South Pacific Ocean.  The ridge will steer Oma in a southwesterly direction during the next several days.  On its anticipated track the center of Tropical Cyclone Oma will pass west of New Caledonia.  However, rainbands on the eastern side of the circulation could drop locally heavy rain over New Caledonia.  Those rainbands could also produce winds to tropical storm force over northern New Caledonia.

Tropical Cyclone Oma Strengthens to Equivalent of Hurricane/Typhoon

Tropical Cyclone Oma strengthened to the equivalent of a hurricane/typhoon over the Coral Sea north of New Caledonia on Friday.  At 1:00 p.m. EST on Friday the center of Tropical Cyclone Oma was located at latitude 15.4°S and longitude 164.2°E which put it about 300 miles (485 km) north of New Caledonia.  Oma was moving toward the west-southwest at 4 m.p.h. (6 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 969 mb.

The circulation around Tropical Cyclone Oma continued to become better organized on Friday.  A ring of thunderstorms wrapped around much of the center of circulation and there were indications on satellite images that an eye could be forming.  The strongest thunderstorms were the northwestern part of the ring.  The ring was thinner east of the center and there were several breaks in that portion of the ring.  Storms near the center were generating upper level divergence which was pumping mass away from core of the tropical cyclone.  Bands of showers and thunderstorms were revolving around the center of circulation.  The bands were stronger north and west of the center and the stronger winds were occurring in that part of Tropical Cyclone Oma.

Tropical Cyclone Oma will move through an environment favorable for intensification during the next day or two.  Oma will move over water where the Sea Surface Temperature is near 30°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Oma is likely to strengthen more and there is a chance that it could intensify into the equivalent of a major hurricane.

Tropical Cyclone Oma will move slowly around the western end of a strengthening subtropical ridge.  The ridge will steer Oma slowly toward the southwest during the next 24 hours.  Tropical Cyclone Oma will move toward the southwest more rapidly in a day or so when the subtropical ridge is stronger.  On its anticipated track the core of Tropical Cyclone Oma could pass near the northernmost islands of New Caledonia in 24 to 36 hours.