Monthly Archives: March 2015

Maysak Near Super Typhoon Intensity East of Yap

Maysak intensified rapidly on Monday and it is near Super Typhoon intensity.  At 11:00 a.m. EDT on Monday the center of Typhoon Maysak was located at latitude 9.6°N and longitude 142.5°E which put it about 300 miles east of Yap and about 1450 miles east-southeast of Luzon.  Maysak was moving toward the west-northwest at 14 m.p.h.  The maximum sustained wind speed was 140 m.p.h. and there were gusts to 170 m.p.h.  The minimum surface pressure was 929 mb.

Maysak moved into an area of light upper level winds on Monday, which allowed the well-developed upper level divergence to pump out mass in all directions.  As a result, the surface pressure decreased rapidly and the wind speed increased quickly.  The circulation is very symmetrical and Maysak has a tight inner core.  The eye is exhibiting a stadium effect on visible satellite images which is indicative of a very strong tropical cyclone.  Maysak continues to move over warm Sea Surface Temperatures and it could intensify into the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale.  When tropical cyclones get as strong as Maysak is, they often go through eyewall replacement cycles which result in periodic fluctuations of intensity.  On its west-northwesterly track Maysak will gain latitude and it could move into an area of stronger vertical wind shear in 24 to 48 hours.  Increased wind shear would weaken it.

A strong subtropical ridge is steering Maysak toward the west-northwest and that motion is expected to continue in the short term.  The ridge may weaken somewhat in about 24 hours and that would allow Maysak to move in a more northwesterly direction for a day or two.  Later in the week a subtropical ridge is expected to build again and steer Maysak more toward the west again.  On its projected track, the center of Maysak would pass north of Yap in about 24 hours.  However, residents should monitor the typhoon closely in case it takes a more southerly track which would bring the core of stronger winds closer to Yap.  Over the longer term, Maysak could approach Luzon and the northern Philippines in five or six days and it could still be a typhoon at that time.

Typhoon Maysak Passing South of Guam and Intensifying

Typhoon Maysak continued to intensify on Sunday.  At 11:00 p.m. EDT on Sunday the center of Typhoon Maysak was located at latitude 8.4°N and longitude 146.9°E which put it about 370 miles south-southeast of Guam and about 600 miles east of Yap.  Maysak was moving toward the west at 17 m.p.h.  The maximum sustained wind speed was 100 m.p.h. and there were gusts to 125 m.p.h.  The minimum surface pressure was 959 mb.

Maysak is moving over warm Sea Surface Temperatures and it has plenty of energy available to support further intensification.  Upper level winds blowing from the southeast are creating some wind shear, but it is not enough to stop the intensification.  The circulation is symmetrical and it has well developed upper level outflow.  Maysak is expected to intensify for another day or two and it could become the equivalent of a major hurricane.

A subtropical ridge is steering Maysak on a track that is moving it just north of due west.  This motion is expected to continue for another 24 to 48 hours.  After that time the ridge is expected to weaken slightly and Maysak is expected to move more toward the northwest.  The center of Maysak should pass south of Guam during the next 12 hours.  On the projected track Maysak would approach Yap in about 36 hours.  It could be a very strong typhoon by that time and it would pose a distinct risk for Yap.

Typhoon Maysak Crossing Chuuk

The core of Typhoon Maysak is passing very near Chuuk.  At 11:00 p.m. EDT on Saturday the center of Maysak was located at latitude 7.3°N and longitude 151.8°E which put it about 15 miles south-southwest of Chuuk and about 600 miles east-southeast of Guam.  It was moving toward the west at 12 m.p.h.  The maximum sustained wind sped was 80 m.p.h. and there were gusts to 100 m.p.h.  The minimum surface pressure was 971 mb.

Maysak is moving over water where the Sea Surface Temperature is around 29°C.  The upper level winds are blowing from the east, but they are only generating modest amounts of vertical wind shear.  The circulation is very well organized and upper level outflow is pumping out mass in all directions.  In this favorable environment Typhoon Maysak is expected to continue to intensify for another two or three days.

A strong subtropical ridge is steering Maysak toward the west and that motion is expected to continue for another day or two.  The ridge is expected to weaken somewhat later next week and Maysak could move more toward the west-northwest during the middle portion of the week.    On its projected track Maysak would pass south of Guam in about 36 hours and it could be approaching Yap in 48 to 60 hours.

 

Tropical Storm Maysak (04W) Forms East of Chuuk

An area of thunderstorms, that generated mesoscale vortices during the past several days developed a persistent center of circulation on Friday and was classified as Tropical Storm Maysak (04W).  At 11:00 p.m. EDT on Friday the center of Tropical Storm Maysak was located at latitude 7.6°N and longitude 154.9°E which put it about 200 miles east of Chuuk and about 800 miles east-southeast of Guam.  Maysak was moving toward the west at 12 m.p.h.  The maximum sustained wind speed was 50 m.p.h. and there were gusts to 65 m.p.h.  The minimum surface pressure was 989 mb.

Maysak formed over very warm Sea Surface Temperatures, but moderate upper level easterly winds were causing vertical wind shear and kept shearing the top off the circulation.  When the system moved further west, it moved into an area where the upper level winds were not as strong and a center of circulation develop and persisted.  The organization of the circulation has increased during the past 12 hours and Maysak has been intensifying.  It is expected to take a westerly track which would keep it in an area where the upper level winds should not be too strong.  Steady intensification is expected and rapid intensification is possible.  Maysak could become a typhoon in 24 hours and it could become the equivalent of a major hurricane in three or four days.

A subtropical ridge is steering Maysak toward the west and it is expected to keep steering it in that direction during the next few days.  The projected track takes Maysak very near Chuuk during the next 18 to 24 hours.  In a few days it is projected to pass between Guam and Yap and head in the general direction of the northern Philippines.

 

Tropical Cyclone Nathan Weakening Over Northern Australia

The center of Tropical Cyclone Nathan moved inland between Maningrida and Goulburn Island on the northern coast of Australia on Monday.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Nathan was located at latitude 12.2°S and longitude 133.5°E which put it about 30 miles east-northeast of Gunbalanya, about 45 miles south of Goulburn Island and about 210 miles east of Darwin, Australia.  Nathan was moving toward the southwest at 8 m.p.h.  The maximum sustained wind speed was 45 m.p.h. and there were gusts to 60 m.p.h.  The minimum surface pressure was 989 mb.

A combination of factors contributed to the weakening of Nathan.  As the center of circulation moved inland, the clockwise flow pulled in drier air from the interior of Australia.  The drier air reduced the number of thunderstorms and decreased the amount of latent energy released in the remaining thunderstorms.  Since the release of latent energy drives the circulation in a tropical cyclone, the wind speed has been decreasing as well.  In addition, northerly winds in the upper levels are creating moderate vertical wind shear over the top of Nathan.  The wind shear is displacing many of the remaining thunderstorms to the south side of the circulation.  The asymmetrical development of thunderstorms has weakened the inner core of the circulation.  As long as the center of circulation remains over land, it is likely to weaken further.

A subtropical ridge to the south of Nathan is expected to steer it in a mainly westerly direction.  The projected track would take the center of Nathan south of Darwin and keep it over land for about another 36 hours.  The circulation could be fairly weak by the time it moves back over water west of Darwin.  The water west of Darwin is warm and so, it is possible that more thunderstorms could develop, if there is a coherent circulation when the system moves back over the water.

Tropical Cyclone Nathan Moving Parallel to the Northern Coast of Australia

The center of Tropical Cyclone Nathan moved across the northeastern portion of Arnhem Land and it has emerged over the Arafura Sea.  At 10:00 p.m. EDT on Sunday the center of Tropical Cyclone Nathan was located at latitude 11.6°S and longitude 134.7°E which put it about 45 miles northeast of Maningrida, about 35 miles north-northwest of Milingimbi and about 280 miles east-northeast of Darwin, Australia.  Nathan 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 95 m.p.h.  The minimum surface pressure was 974 mb.

The core of the circulation was relatively intact when the center of Nathan moved back over water and it had an apparent eye on some satellite imagery and radar displays.  The surface temperatures are quite warm in the Arafura Sea and thunderstorms continue to develop around the southern and western sides of the circulation.  Less convection is occurring on the eastern side of Nathan.  It is possible the moving across land and proximity to the coast is allowing some drier air to be entrained into the circulation.  Light westerly winds in the upper levels may also be creating some vertical wind shear.  The intact core and warm water could allow Nathan to intensify somewhat on Monday.

Nathan is being steered toward the west by a subtropical ridge located to its south.  The ridge is expected to continue to steer Nathan in a general westerly direction for another 24 hours.  The projected track would keep the center of circulation over water.  The ridge is expected to weaken a bit in a day or so, which could allow Nathan turn southwestward and make another landfall on the north coast of Australia.  The southwesterly turn could produce a landfall between Maningrida and Croker Island.

Nathan has a relatively small circulation but it is strong enough to cause wind damage and a significant storm surge near where the center makes landfall.  It could also produce locally heavy rainfall and flooding in inland areas.

Tropical Cyclone Nathan Making Landfall in Northern Australia

The center of Tropical Cyclone Nathan is moving inland near Nhulunbuy, Australia.  At 9:00 p.m. EDT on Saturday the center of Tropical Cyclone Nathan was located at latitude 12.6°S and longitude 136.8°E which put it about 25 miles south of Nhulunbuy and about 90 miles north-northeast of Alyangula, Australia.  Nathan was moving toward the northwest at 8 m.p.h.  The maximum wind speed was 75 m.p.h. and there were gusts to 90 m.p.h.  The minimum surface pressure was 979 mb.

The atmospheric environment around Tropical Cyclone Nathan is favorable for intensification.  The upper level winds are light.  The circulation is well organized and there is upper level outflow pumping out mass.  Outflow channels extend to the northwest and southeast.  However, as the center moves over land, the circulation will weaken.  The center is expected to cross the northeastern corner of Arnhem Land and move back over water in a few hours.  The potential for re-intensification will depend on how far away from the coast the center moves.

A subtropical ridge located southwest of Nathan is steering it toward the northwest.  The ridge is expected to continue to steer the tropical cyclone in that direction for another day or so.  After that time Nathan is expected to start moving more toward the west and eventually toward the southwest and make another landfall on the northern coast of Australia,

Nathan is strong enough to cause some wind damage.  It could also produce a significant storm surge near where the center is making landfall.  Locally heavy rainfall could create possible flooding at inland locations.

Tropical Cyclone Nathan Crossing Cape York Peninsula

Tropical Cyclone Nathan made landfall in Queensland and it is now crossing the Cape York Peninsula.  At 11:00 a.m. EDT on Friday the center of Tropical Cyclone Nathan was located at latitude 14.4°N and longitude 142.2°E which put it about 75 miles west-southwest of Coen, about 80 miles north-northeast of Kowanyama and about 530 miles east-southeast of Alyangula, Australia.  Nathan was moving toward the west at 11 m.p.h.  The maximum sustained wind speed was 65 m.p.h. and there were gusts to 80 m.p.h.  The minimum surface pressure was 984 mb.

Nathan has been weakening as it moves across the Cape York Peninsula in Northern Queensland.  However, it is approaching the Gulf of Carpentaria and the center of circulation will soon be back over water.  The circulation is still mostly intact and it has well developed upper level outflow.  The water at the surface of the Gulf of Carpentaria is very warm.  In addition, the upper level winds around Nathan are very light and there is very little vertical wind shear.  So, the environment around Nathan is quite favorable for intensification and it is possible that a period of rapid re-intensification could occur.

A subtropical ridge is expected to steer Nathan in a west-northwesterly direction during the next several days.  The projected track would have Nathan making another landfall in the Northern Territory between Port Roper and Nhulunbuy in 24 to 36 hours.  If Nathan does reintensify it could bring strong winds and a storm surge to the coast.  It will also be capable of producing locally heavy rainfall and flooding in inland locations.

 

Severe Tropical Cyclone Nathan Making Landfall in Queensland

The center of Severe Tropical Cyclone Nathan is very near the coast of Queensland and it is about to make landfall between Cape Flattery and Cape Melville.  At 11:00 a.m. EDT on Thursday the center of Nathan was located at latitude 14.7°S and longitude 145.6°E which put it about 20 miles northeast of Cape Flattery and about 50 miles north-northeast of Cooktown, Australia.  Nathan was moving toward the west at 11 m.p.h.  The maximum sustained wind speed was 105 m.p.h. and there were gusts to 140 m.p.h.  The minimum surface pressure was 953 mb.

A subtropical ridge is steering Nathan westward and this motion is expected to continue.  The center of Nathan will make landfall soon between Cape Flattery and Cape Melville.  It is capable of producing wind damage and a significant storm surge near where the center crosses the coast.  Nathan could also produce locally heavy rainfall and flooding in some locations.  It is possible that the circulation could emerge intact over the Gulf of Carpentaria.  In that case Nathan could re-intensify somewhat and possibly pose a risk to the western side of the Gulf.

Tropical Cyclone Nathan Approaching Queensland Coast

Tropical cyclone Nathan is moving toward the coast of Queensland and it is intensifying.  At 10:00 p.m. EDT on Wednesday the center of Tropical Cyclone Nathan was located at latitude 14.7°S and longitude 147.4°E which put it about 140 miles east of Cape Flattery, about 190 miles east-northeast of Cooktown and about 200 miles east of Cape Melville.  Nathan was moving toward the west at 7 m.p.h.  The maximum sustained wind speed was 95 m.p.h. and there were gusts to 120 m.p.h.  The minimum surface pressure was 959 mb.

Nathan intensified quickly on Wednesday and it is close to being the equivalent of a Category 2 hurricane on the Saffir-Simpson Scale.  The core of the circulation is moving over warm Sea Surface Temperatures.  The upper level winds are light and there is very little vertical wind shear.  Nathan is in a favorable environment and it has well developed upper level outflow.  It is expected to increase in intensity until it makes landfall.

A subtropical ridge building northwest of Nathan is expected to steer it west toward the cost of Queensland.  On the projected track, the center will make landfall between Cape Melville and Cooktown in 12 to 18 hours.  Nathan has the potential to bring strong winds near where the center makes landfall.  Even though the circulation is relatively small, it also has the potential to generate a significant storm surge near the location of landfall.  The strength of the circulation also will create the potential for locally heavy rainfall and flooding as the cyclone moves inland.