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Typhoon Sinlaku Bears Down on the Marianas

Typhoon Sinlaku was bearing down on the Marianas on Monday morning.  At 11:00 a.m. EDT on Monday the center of Typhoon Sinlaku was located at latitude 13.3°N and longitude 147.2°E which put the center about 190 miles (335 km) east of Guam.  Sinlaku was moving toward the northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 175 m.p.h. (285 km/h) and there were wind gusts to 205 m.p.h. (335 km/h).  The minimum surface pressure was 903 mb.

Typhoon Warnings are in effect for Rota, Tinian, and Saipan.

Tropical Storm Warnings are in effect for Guam, Pagan, and Alamagan.

A Typhoon Watch is in effect for Guam.

A Tropical Storm Watch is in effect for Agrihan.

Typhoon Sinlaku was maintaining its intensity as it was bearing down on the Mariana’s on Monday morning.  Sinlaku was the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  A circular eye with a diameter of 17 miles (28 km) was as the center of Sinlaku’s circulation.  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 Typhoon Sinlaku.  Storms near the center of Sinlaku generated upper level divergence that pumped mass away from the typhoon.  The removal of mass in the upper levels of the atmosphere was nearly equal to the convergence of mass in the lower levels.  So, the surface pressure was nearly constant.

The circulation around Typhoon Sinlaku was large.  Winds to typhoon force extended out 80 miles (130 km) from the center of Sinlaku’s circulation.  Winds to tropical storm force extended out 290 miles (465 km) from the center of Typhoon Sinlaku.

The Hurricane Intensity Index (HII) for Typhoon Sinlaku is 40.4.  The Hurricane Size Index (HSI) is 28.4 and the Hurricane Wind Intensity Size Index (HWISI) is 68.8.  Typhoon Sinlaku is similar in intensity to Hurricane Maria when Maria was at its peak strength in 2017.  Sinlaku is bigger than Maria was.

Typhoon Sinlaku will move through an environment favorable for a very powerful typhoon during the next 24 hours.  Sinlaku will move over water where the Sea Surface Temperatures are near 28°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Sinlaku is likely to maintain its intensity during the next 24 hours unless an eyewall replacement cycle occurs.  Sinlaku could weaken if the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form, then an eyewall replacement cycle would cause Typhoon Sinlaku to weaken.

Typhoon Sinlaku will move around the western part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Sinlaku toward the northwest during the next 24 hours.  On its anticipated track, the center of Typhoon Sinlaku will be near Tinian and Saipan in less than 24 hours.

Typhoon Sinlaku could be the equivalent of a Category 5 hurricane when it reaches Tinian and Saipan.  Sinlaku will be capable of causing catastrophic damage in Tinian and Saipan.  Typhoon Sinlaku will bring also strong winds and locally heavy rain to Guam, Rota, Pagan, and Alamagan. Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for Guam, Rota, Tinian, and Saipan.

Typhoon Sinlaku could also cause a storm surge of up to 17 feet (5.1 meters) along parts of the coasts of the Marianas.

Typhoon Sinlaku Intensifies to Equivalent of Cat. 5 Hurricane

Typhoon Sinlaku intensified to the equivalent of a category 5 hurricane on the Saffir-Simpson Scale on Sunday.  At 11:00 a.m. EDT on Sunday the center of Typhoon Sinlaku was located at latitude 11.4°N and longitude 149.9°E which put the center about 410 miles (660 km) east-southeast of Guam.  Sinlaku was moving toward the north-northwest at 11 m.p.h. (17 km/h).  The maximum sustained wind speed was 175 m.p.h. (285 km/h) and there were wind gusts to 205 m.p.h. (335 km/h).  The minimum surface pressure was 902 mb.

Typhoon Warnings were in effect for Rota, Tinian, and Saipan.

A Tropical Storm Warning was in effect for Guam.

A Typhoon Watch was also in effect for Guam.

Typhoon Sinlaku rapidly intensified to the equivalent of a Category 5 hurricane on Sunday.  A circular eye with a diameter of 20 miles (32 km) was as the center of Sinlaku’s circulation.  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 Typhoon Sinlaku.  Storms near the center of Sinlaku generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The circulation around Typhoon Sinlaku was large.  Winds to typhoon force extended out 60 miles (95 km) from the center of Sinlaku’s circulation.  Winds to tropical storm force extended out 275 miles (445 km) from the center of Typhoon Sinlaku.

The Hurricane Intensity Index (HII) for Typhoon Sinlaku is 40.4.  The Hurricane Size Index (HSI) is 21.3 and the Hurricane Wind Intensity Size Index (HWISI) is 61.7.  Typhoon Sinlaku is similar in size and intensity to Hurricane Maria when Maria was at its peak strength in 2017.

Typhoon Sinlaku will move through an environment favorable for a very powerful typhoon during the next 24 hours.  Sinlaku will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Sinlaku is likely to maintain its intensity during the next 24 hours unless an eyewall replacement cycle occurs.  Sinlaku could weaken if the inner end of a rainband wraps around the existing eye and eyewall.  If concentric eyewalls form, then an eyewall replacement cycle would cause Typhoon Sinlaku to weaken.

Typhoon Sinlaku will move around the western part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Sinlaku toward the northwest during the next 24 hours.  On its anticipated track, Typhoon Sinlaku will approach the Marianas in less than 35 hours.

Typhoon Sinlaku will be the equivalent of a major hurricane when it approaches the Marianas.  Sinlaku will bring very strong winds and locally heavy rain to Guam, Rota, Tinian, and Saipan.   Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for Guam, Rota, Tinian, and Saipan.

Typhoon Sinlaku could also cause a storm surge of up to 17 feet (5.1 meters) along parts of the coasts of the Marianas.

Typhoon Sinlaku Intensifies to Equivalent of a Major Hurricane

Typhoon Sinlaku intensified to the equivalent of a major hurricane as it moved southeast of the Marianas on Saturday evening.  At 11:00 p.m. EDT on Saturday the center of Typhoon Sinlaku was located at latitude 10.2°N and longitude 151.0°E which put the center about 505 miles (815 km) east-southeast of Guam.  Sinlaku was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 944 mb.

Typhoon Watches are in effect for Guam, Rota, Tinian, and Saipan.

Typhoon Sinlaku continued to strengthen on Saturday evening as it moved toward the southern Marianas.  A circular eye with a diameter of 20 miles (32 km) was as the center of Sinlaku’s circulation.  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 Typhoon Sinlaku.  Storms near the center of Sinlaku generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The circulation around Typhoon Sinlaku was large.  Winds to typhoon force extended out 60 miles (95 km) from the center of Sinlaku’s circulation.  Winds to tropical storm force extended out 250 miles (400 km) from the center of Typhoon Sinlaku.

The Hurricane Intensity Index (HII) for Typhoon Sinlaku was 23.6.  The Hurricane Size Index (HSI) was 21.2 and the Hurricane Wind Intensity Size Index (HWISI) was 44.8.

Typhoon Sinlaku will move through an environment favorable for intensification during the next 24 hours.  Sinlaku will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge that is over the Western North Pacific Ocean.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Typhoon Sinlaku will intensify during the next 24 hours.  Sinlaku could intensify rapidly at times.  Typhoon Sinlaku could strengthen to the equivalent of a Category 5  hurricane on the Saffir-Simpson Scale during the next 36 hours.

Typhoon Sinlaku will move around the southwestern part of a high pressure system that is over the Western North Pacific Ocean.  The high pressure system will steer Sinlaku toward the northwest during the next 24 hours. On its anticipated track, Typhoon Sinlaku will approach the southern Marianas in less than 48 hours.

Typhoon Sinlaku will be the equivalent of a major hurricane when it approaches the southern Marianas.  Sinlaku will bring very strong winds and locally heavy rain to Guam, Rota, Tinian, and Saipan.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for Guam, Rota, Tinian, and Saipan.

Typhoon Sinlaku could also cause a storm surge of up to 14 feet (4.3 meters) along parts of the coasts of the southern Marianas.

Tropical Cyclone Maila Weakens

Tropical Cyclone Maila weakened over the Solomon Sea on Thursday.  At 11:00 a.m. EDT on Thursday the center of Tropical Cyclone Maila was located at latitude 8.3°S and longitude 154.3°E which put the center about 460 miles (740 km) east of Port Moresby, Papua New Guinea.  Maila was moving toward the west at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 967 mb.

Tropical Cyclone Maila was continuing to weaken as it moved toward the southeastern part of Papua New Guinea on Thursday.  Maila continued to move slowly back over cooler water that it had mixed to the surface of the Solomon Sea earlier this week.  The remnant of a circular eye was still present at the center of Maila’s circulation.  The remnant 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 Tropical Cyclone Maila.  Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass of mass in the upper levels of the atmosphere was less than the convergence of mass in the lower levels.  So, the surface pressure was increasing.

The size of Tropical Cyclone Maila did not change much during the past 24 hours.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Maila’s circulation.  Winds to tropical storm force extended out 160 miles (260 km) from the center of Tropical Cyclone Maila.

The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 16.4.  The Hurricane Size Index (HSI) is 16.6 and the Hurricane Wind Intensity Size Index (HWISI) is 33.0. Tropical Cyclone Maila is similar in intensity to Hurricane Idalia when Idalia hit Florida in 2023.  Maila is bigger than Idalia was.

Tropical Cyclone Maila will continue to be in an environment that will be slightly unfavorable for a strong tropical cyclone during the next 24 hours.  Maila will be over water where the Sea Surface Temperatures were originally near 30°C.  It will be under the middle of an upper level ridge that is over the Solomon Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean continue to mix cooler water to the surface.  Maila will continue to move back over cooler water that has already mixed to the surface of the ocean earlier this week.  The cooler water is likely to prevent further intensification of Tropical Cyclone Maila.  Maila is likely to continue to weaken slowly during the next 24 hours.

Tropical Cyclone Maila will move around the northern side of a high pressure system that is developing over the Coral Sea.  The high pressure system will steer Maila toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Maila will continue to move toward the southeastern part of Papua New Guinea.

The center of Tropical Cyclone Maila will approach Woodlark Island in 24 hours.  Maila will bring strong winds and locally heavy rain to the Kiriwina Islands, the D’Entrecasteaux Islands, and the Louisiade Archipelago.  Heavy rain could cause flash floods in some locations. Tropical Cyclone Maila will be capable of causing serious damage.  Maila could also produce a storm surge of up to 10 feet (3 meters) along the coasts of some of the islands.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu was finishing a transition to a powerful extratropical storm as it moved toward New Zealand.  The New Zealand Met Service issued a Strong Wind Watch and a Heavy Rain Watch for the North Island.  At 5:00 a.m. EDT on Thursday the center of Tropical Cyclone Vaianu was located at latitude 27.1°S and longitude 179.0°E which put the center about 625 miles (1000 km) north of Auckland New Zealand.  Vaianu was moving toward the south-southeast at 7 m.p.h. (11 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 981 mb.

Tropical Cyclone Maila Moves Toward Papua New Guinea

Tropical Cyclone Maila started to move slowly toward the southeastern part of Papua New Guinea on Wednesday.  At 11:00 a.m. EDT on Wednesday the center of Tropical Cyclone Maila was located at latitude 8.6°S and longitude 155.6°E which put the center about 550 miles (890 km) east of Port Moresby, Papua New Guinea.  Maila was moving toward the west at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 951 mb.

Tropical Cyclone Maila was weakening slowly as it started to move toward the southeastern part of Papua New Guinea on Wednesday.  Maila was moving over cooler water that it had mixed to the surface of the Solomon Sea earlier this week.  A circular eye was still present at the center of Maila’s circulation.  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 Tropical Cyclone Maila.  Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone. The removal of mass of mass in the upper levels of the atmosphere was less than the convergence of mass in the lower levels.  So, the surface pressure was increasing.

The area of the strongest winds in Tropical Cyclone Maila was a little smaller on Wednesday.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Maila’s circulation.  Winds to tropical storm force extended out 145 miles (235 km) from the center of Tropical Cyclone Maila.

The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 22.1.  The Hurricane Size Index (HSI) is 11.7 and the Hurricane Wind Intensity Size Index (HWISI) is 33.8. Tropical Cyclone Maila is similar in intensity to Hurricane Milton when Milton hit Florida in 2024.  Maila is not as big as Milton was.

Tropical Cyclone Maila will continue to be in an environment that will be slightly unfavorable for a strong tropical cyclone during the next 24 hours.  Maila will be over water where the Sea Surface Temperatures were originally near 30°C.  It will be under the middle of an upper level ridge that is over the Solomon Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean continue to mix cooler water to the surface.  Maila will continue to move back over cooler water that has already mixed to the surface of the ocean earlier this week.  The cooler water is likely to prevent further intensification of Tropical Cyclone Maila.  Maila is likely to continue to weaken slowly during the next 24 hours.

Tropical Cyclone Maila will move around the northern side of a high pressure system that is developing over the Coral Sea.  The high pressure system will steer Maila toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Maila will move toward the southeastern part of Papua New Guinea.

Tropical Cyclone Maila will approach Woodlark Island in 36 hours.  Maila will bring strong winds and locally heavy rain to the Kiriwina Islands, the D’Entrecasteaux Islands, and the Louisiade Archipelago.  Heavy rain could cause flash floods in some locations.  Tropical Cyclone Maila will be capable of causing serious damage.  Maila could also produce a storm surge of up to 10 feet (3 meters) along the coasts of some of the islands.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu was making a transition to a powerful extratropical storm as it moved toward New Zealand.  The New Zealand Met Service issued a Strong Wind Watch and a Heavy Rain Watch for the North Island.  At 5:00 a.m. EDT on Wednesday the center of Tropical Cyclone Vaianu was located at latitude 23.9°S and longitude 177.9°E which put the center about 840 miles (1355 km) south of Auckland New Zealand.  Vaianu was moving toward the south-southeast at 15 m.p.h. (24 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. (165 km/h).  The minimum surface pressure was 973 mb.

Tropical Cyclone Maila Intensifies to Equivalent of Cat. 4 Hurricane

Tropical Cyclone Maila intensified to the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale on Tuesday.  At 5:00pa.m. EDT on Tuesday the center of Tropical Cyclone Maila was located at latitude 9.5°S and longitude 155.9°E which put the center about 565 miles (910 km) east of Port Moresby, Papua New Guinea.  Maila was moving toward the northwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 145 m.p.h. (235 km/h) and there were wind gusts to 175 m.p.h. (285 km/h).  The minimum surface pressure was 930 mb.

Tropical Cyclone Maila intensified to the equivalent of a Category 4 hurricane as it continued to meander over the Solomon Sea on Tuesday.  A circular eye with a diameter of 28 miles (45 km) was present at the center of Maila’s circulation.  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 Tropical Cyclone Maila.  Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Cyclone Maila was fairly symmetrical.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Maila’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Tropical Cyclone Maila.

The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 29.9.  The Hurricane Size Index (HSI) is 16.5 and the Hurricane Wind Intensity Size Index (HWISI) is 46.4.  Tropical Cyclone Maila is similar in size and intensity to Hurricane Ida when Ida hit Louisiana in 2021.

Tropical Cyclone Maila will continue to be in an environment that will be slightly unfavorable for a strong tropical cyclone during the next 24 hours.  Maila will be over water where the Sea Surface Temperatures were originally near 30°C.  It will be under the middle of an upper level ridge that is over the Solomon Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean are mixing cooler water to the surface.  Maila will move back over cooler water that has already mixed to the surface of the ocean.  The cooler water is likely to prevent further intensification of Tropical Cyclone Maila.  Maila is likely to weaken slowly during the next 24 hours.

Tropical Cyclone Maila will move around the northern side of a high pressure system that is developing over the Coral Sea.  The high pressure system will steer Maila toward the west during the next 24 hours.  On its anticipated track, Tropical Cyclone Maila will move toward the southeastern part of Papua New Guinea.

Tropical Cyclone Maila could approach Woodlark Island in less than 48 hours.  Maila will bring strong winds and locally heavy rain to the Kiriwina Islands, the D’Entrecasteaux Islands, and the Louisiade Archipelago.  Heavy rain could cause flash floods in some locations.  Tropical Cyclone Maila will be capable of causing major damage.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu started to weaken as it moved away from Fiji.  At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Vaianu was located at latitude 21.6°S and longitude 177.3°E which put the center about 255 miles (410 km) south of Nadi, Fiji.  Vaianu was moving toward the southeast at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 962 mb.

Tropical Cyclone Maila Strengthens to Equivalent of a Major Hurricane

Tropical Cyclone Maila strengthened to the equivalent of a major hurricane as it moved slowly over the Solomon Sea on Monday night.  At 5:00 a.m. EDT on Tuesday the center of Tropical Cyclone Maila was located at latitude 9.9°S and longitude 156.5°E which put the center about 605 miles (970 km) east of Port Moresby, Papua New Guinea.  Maila was moving toward the east at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 953 mb.

Tropical Cyclone Maila intensified to the equivalent of a major hurricane on Monday night.  A circular eye was present at the center of Maila’s circulation.  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 Tropical Cyclone Maila. Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Cyclone Maila was fairly symmetrical.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Maila’s circulation.  Winds to tropical storm force extended out 140 miles (220 km) from the center of Tropical Cyclone Maila.

The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 20.6.  The Hurricane Size Index (HSI) is 16.5 and the Hurricane Wind Intensity Size Index (HWISI) is 37.1.  Tropical Cyclone Maila is similar in intensity to Hurricane Rita when Rita hit Southwest Louisiana in 2005.  Maila is smaller than Rita was.

Tropical Cyclone Maila will continue to be in an environment that will be mostly favorable for intensification during the next 24 hours.  Maila will be over water where the Sea Surface Temperatures are near 30°C.  It will be under the middle of an upper level ridge that is over the Solomon Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean are mixing cooler water to the surface.  If enough cooler water mixes to the surface of the ocean, then the cooler water could stop the intensification of Maila.  Tropical Cyclone Maila could intensify slowly during the next 24 hours, unless too much cooler water mixes to the surface of the ocean.

Tropical Cyclone Maila will continue to be in a region where the steering winds are weak during the next 24 hours. Tropical Cyclone Maila is forecast to meander over the Solomon Sea because the steering winds are weak.  A high pressure system is forecast to develop over the Coral Sea later this week.  The high pressure system will steer Maila toward the west after it develops.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu passed southwest of Fiji.  At 5:00 a.m. EDT on Tuesday the center of Tropical Cyclone Vaianu was located at latitude 19.7°S and longitude 175.6°E which put the center about 175 miles (285 km) southwest of Nadi, Fiji.  Vaianu was moving toward the south-southeast at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 954 mb.

Tropical Cyclone Maila Meanders over the Solomon Sea

Tropical Cyclone Maila continued to strengthen on Monday as it meandered over the Solomon Sea.   At 11:00 a.m. EDT on Monday the center of Tropical Cyclone Maila was located at latitude 9.7°S and longitude 155.6°E which put the center about 555 miles (895 km) east of Port Moresby, Papua New Guinea.  Maila was moving toward the east at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 958 mb.

Tropical Cyclone Maila continued to strengthen on Monday as it meandered over the Solomon Sea.  A small circular eye was at the center of Maila’s circulation.  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 Tropical Cyclone Maila.  Storms near the center of Maila generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The distribution of wind speeds around Tropical Cyclone Maila was fairly symmetrical.  Winds to hurricane/typhoon force extended out 50 miles (80 km) from the center of Maila’s circulation.  Winds to tropical storm force extended out 155 miles (250 km) from the center of Tropical Cyclone Maila.

The Hurricane Intensity Index (HII) for Tropical Cyclone Maila is 19.2.  The Hurricane Size Index (HSI) is 17.0 and the Hurricane Wind Intensity Size Index (HWISI) is 36.2.  Tropical Cyclone Maila is similar in intensity to Hurricane Sally when Sally hit South Alabama in 2020.  Maila is bigger than Sally was.

Tropical Cyclone Maila will continue to be in an environment that will be mostly favorable for intensification during the next 24 hours.  Maila will be over water where the Sea Surface Temperatures are near 30°C. It will be under the northern part of an upper level ridge that is over the Solomons.  The upper level ridge will produce easterly winds that will blow toward the top of Maila’s circulation.  Those winds will cause some vertical wind shear.  The vertical wind shear will inhibit intensification, but the wind shear will not be enough to prevent intensification.  Since Tropical Cyclone Maila has been moving slowly over the Solomon Sea, the strong winds near the surface of the ocean are mixing cooler water to the surface.  If enough cooler water mixes to the surface of the ocean, then the cooler water could stop the intensification of Maila. Tropical Cyclone Maila could intensify slowly during the next 24 hours, unless too much cooler water mixes to the surface of the ocean.  If Maila intensifies it will strengthen to the equivalent of a major hurricane.

Tropical Cyclone Maila will continue to be in a region where the steering winds are weak during the next 24 hours.  Tropical Cyclone Maila is forecast to meander over the Solomon Sea because the steering winds are weak.

Elsewhere over the South Pacific Ocean, Tropical Cyclone Vaianu continued to intensify west of Fiji.  At 11:00 a.m. EDT on Monday the center of Tropical Cyclone Vaianu was located at latitude 16.8°S and longitude 174.1°E which put the center about 230 miles (375 km) west of Nadi, Fiji.  Vaianu was moving toward the southeast at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 959 mb.

Tropical Cyclone Narelle Hits Western Australia

Tropical Cyclone Narelle hit Western Australia west of Exmouth on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Tropical Cyclone Narelle was located at latitude 23.2°S and longitude 113.7°E which put the center about 18 miles (130 km) south-southwest of Exmouth, Australia.  Narelle was moving toward the south-southwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 955 mb.

The Australian Bureau of Meteorology issued a Warning that is in effect for the portion of the coast from Onslow to Jurien Bay.  The Warning includes Exmouth, Coral Bay, Carnarvon, Denham, and Geraldton.

Tropical Cyclone Narelle was the equivalent of a major hurricane when it made landfall on the coast of Western Australia.  Narelle may have been in the middle of an eyewall replacement cycle at the time of landfall.

The circulation around Tropical Cyclone Narelle was large.  Winds to hurricane/typhoon force extended out 80 miles (130 km) from the center of Narelle’s circulation.  Winds to tropical storm force extended out 175 miles (285 km) from the center of Tropical Cyclone Narelle.

The Hurricane Intensity Index (HII) for Tropical Cyclone Narelle was 20.6.  The Hurricane Size Index (HSI) was 28.3 and the Hurricane Wind Intensity Size Index (HWISI) was 48.9.  Tropical Cyclone Narelle was similar in size and intensity to Hurricane Rita when Rita hit Southwest Louisiana in 2005.

Tropical Cyclone Narelle will move around the northeastern part of an upper level trough that is southwest of Australia.  The upper level trough will steer Narelle toward the south-southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Narelle will move along the coast of Western Australia.  The center of Narelle’s circulation will pass near Carnarvon in 12 hours.  The center of Tropical Cyclone Narelle will be near Morawa in 24 hours.

Tropical Cyclone Narelle will bring strong winds and heavy rain to Western Australia.  Narelle will be capable of causing major damage.  Heavy rain is likely to cause flash floods in some locations.

Flood Watches are in effect for western parts of the Pilbara, Gascoyne, Central Coastal, and Lower West Coast catchments.

Tropical Cyclone Narelle could also cause a storm surge of up to 13 feet (4 meters) along parts of the coast.

Tropical Cyclone Narelle Rapidly Intensifies to Equivalent of a Major Hurricane

Tropical Cyclone Narelle rapidly intensified to the equivalent of a major hurricane on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Tropical Cyclone Narelle was located at latitude 18.6°S and longitude 116.8°E which put the center about 150 miles (240 km) north of Karratha, Australia.  Narelle was moving toward the west-southwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 954 mb.

The Australian Bureau of Meteorology issued a Warning that is in effect for the portion of the coast from Pardoo Roadhouse to Cape Cuvier.  The Warning includes Port Hedland, Karratha, Onslow, Exmouth, and Coral Bay.

A Watch is in effect for the portion of the coast from Cape Cuvier to Dongara.  The Watch includes Carnarvon, Denham, and Geraldton.

Tropical Cyclone Narelle rapidly intensified to the equivalent of a major hurricane on Wednesday.  The inner end of a rainband wrapped around the center of Narelle’s circulation.  A large circular eye with a diameter of 45 miles (75 km) formed at the center of Tropical Cyclone Narelle.  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 Narelle’s circulation.  Storms near the center of Narelle generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Tropical Cyclone Narelle increased significantly on Wednesday.  Winds to hurricane/typhoon force extended out 80 miles (130 km) from the center of Narelle’s circulation.  Winds to tropical storm force extended out 185 miles (295 km) from the center of Tropical Cyclone Narelle.

The Hurricane Intensity Index (HII) for Tropical Cyclone Narelle was 22.1  The Hurricane Size Index (HSI) was 24.7 and the Hurricane Wind Intensity Size Index (HWISI) was 46.8.  Tropical Cyclone Narelle was similar in size and intensity to Hurricane Jeanne when Jeanne hit southern Florida in 2004.

Tropical Cyclone Narelle will move through an environment favorable for intensification during the next 24 hours.  Narelle will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the northern part of an upper level ridge that is over Western Australia.  The upper level ridge will produce easterly winds that will blow toward the top of Narelle’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Cyclone Narelle will intensify during the next 24 hours.

Tropical Cyclone Narelle will move around the western side of a high pressure system that is over Australia.  The high pressure system will steer Narelle toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Narelle will approach the coast of Western Australia near Exmouth in 24 hours.  Narelle will move toward the south on Friday when it moves around the western end of the high pressure system.

Tropical Cyclone Narelle will bring strong winds and heavy rain to the coast of Western Australia.  Narelle will be capable of causing major damage.  Heavy is likely to cause flash floods in some locations.

Flood Watches are in effect for western parts of the Pilbara, Gascoyne, Central Coastal, and Lower West Coast catchments.

Tropical Cyclone Narelle could also cause a storm surge of up to 13 feet (4 meters) along parts of the coast.