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Tropical Cyclone Pam Intensifying Quickly

Tropical Cyclone Pam continued to intensify quickly on Tuesday.  At 10:00 p.m. EDT on Tuesday the center of Tropical Cyclone Pam was located at latitude 11.0°S and longitude 169.8°E which put it about 710 miles northwest of Fiji and about 220 miles north-northeast of Espiritu Santo.  Pam was moving toward the southwest at 5 m.p.h.  The maximum sustained wind speed was 115 m.p.h. and there were wind gusts to 135 m.p.h.  The minimum surface pressure was 948 mb.

Pam remains in a very favorable environment.  It is over warm Sea Surface Temperatures and it is in a region of light upper level winds.  The strong core of the tropical cyclone has generated well developed upper level outflow that is pumping out mass in all directions.  Unless it is interrupted by an eyewall replacement cycle, the intensification is likely to continue.

Pam is being steering toward the south by a subtropical ridge located to its east.  The ridge strengthened slightly on Tuesday and pushed the tropical cyclone slightly to the west of the projected track.  The ridge is expected to continue to steer Pam toward the south during the next few days.  The projected track continues to predict that Pam will move east of Vanuatu and New Caledonia and west of Fiji.  However, a further deviation to the west could bring the circulation closer to Vanuatu.  Because of the intensify and large size of the circulation, impacts could be serious if Pam moves over any islands.

 

Tropical Cyclone Pam Intensifying Rapidly Northwest of Fiji

A circulation core developed rapidly in a large area of thunderstorms east of the Solomon Islands and the system was classified as Tropical Cyclone Pam on Monday.  At 10:00 p.m. EDT on Monday the center of Tropical Cyclone Pam was located at latitude 9.8° and longitude 170.4°E which put it about 790 miles northwest of Fiji.  Pam was moving toward the south-southeast at 7 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 974 mb.

Pam intensified rapidly on Monday and reached hurricane intensity within 24 hours of being classified as a tropical cyclone.  It is over Sea Surface Temperatures warmer than 30°C and it has moved into an area where the upper level winds are relatively light.  It normally takes the circulation in a large tropical disturbance a long time to consolidate around an inner core.  However, Pam has well developed upper level outflow, which has pumped out mass and enabled the system to intensify rapidly.  Pam is expected to remain in a very favorable environment and continued rapid intensification is likely.  It could become a very powerful tropical cyclone during the next several days.

Pam is moving around the western end of a subtropical ridge with is steering it in a south-southeasterly direction.  That generally steering pattern is expected to continue for the next several days.  The projected path of Pam carries it west of Fiji and east of Vanuatu and New Caledonia.  Given the large size and intensity of the tropical cyclone, any deviation from the projected path could increase the risk posed by Tropical Cyclone Pam.

 

Tropical Cyclone 15S Forms Over the Mozambique Channel

A low level circulation developed enough organization on the eastern side of a cluster of thunderstorms over the Mozambique Channel to be classified as a tropical cyclone on Thursday.  At 11:00 p.m. EST on Thursday the center of Tropical Cyclone 15S was located at latitude 16.6°S and longitude 42.3° which put it about 110 miles east-southeast of Mogincual, Mozambique and about 200 miles northwest of Maintirano, Madagascar.  It was moving toward the south-southeast at 5 m.p.h.  The maximum sustained wind speed was 40 m.p.h. and there were wind gusts to 50 m.p.h.  The minimum surface pressure was 996 mb.

Southeasterly winds in the upper levels are creating vertical wind shear and most of the stronger thunderstorms are on the western side of the center of circulation.  However, the tropical cyclone is over warm Sea Surface Temperatures and some intensification is possible.  If the upper level winds decrease, the more rapid intensification could occur.  A gradual intensification seems more likely over the short term.

A subtropical ridge of high pressure to the east of the tropical cyclone is steering it slowly to the south.  It is likely to move into a region of weak steering winds  between that ridge of high pressure and another ridge farther to the west.  As a result, the tropical cyclone could move slowly and erratically and even become stationary at times during the next day or two.  Eventually, a third ridge of high pressure is expected to develop to the north of the system and push it westward toward Madagascar.

The tropical cyclone could be a strong tropical storm or near hurricane intensity when it reaches Madagascar.  Some wind damage is possible, but the biggest threat appears to be from locally heavy rainfall and flooding.

 

Tropical Cyclone Glenda Forms South of Diego Garcia

A low level circulation consolidated quickly in a large area of thunderstorms over the south central Indian Ocean and the system was classified as Tropical Cyclone Glenda.  At 11:00 p.m. EST on Tuesday the center of Tropical Cyclone Glenda was located at latitude 17.3°S and longitude 69.8°E which put it about 670 miles south of Diego Garcia and about 1040 miles east-northeast of La Reunion.  Glenda was moving toward the west-southwest at 10 m.p.h.  The maximum sustained wind speed was 65 m.p.h. and there were gusts to 75 m.p.h.  The minimum surface pressure was 982 mb.

Glenda is over warm Sea Surface Temperatures and it has well developed upper level outflow.  The outflow is pumping out mass and the pressure has been decreasing steadily.  Glenda is like to remain in a favorable environment for another 48 hours.  It will likely reach hurricane intensity on Wednesday and it could become the equivalent of a major hurricane on Thursday.

Glenda is being steered to the west-southwest by a subtropical ridge located southeast of it.  This motion is likely to continue for another 24 to 36 hours.  When it approaches the western end of the ridge, it will turn more toward the south.  The projected track keeps Glenda well south of Diego Garcia and has it turning southward well to the east of La Reunion.  As a result, Glenda poses no current threat to any land area.

 

Strong Tropical Cyclone Marcia Moving Over Eastern Queensland

Strong Tropical Cyclone Marcia made landfall a few hours ago on the east coast of Australia northwest of Yeppoon in Queensland.  Marcia is moving roughly parallel to the coast about 25 miles inland from the Pacific Ocean.  At 9:00 p.m. EST on Thursday the center of Tropical Cyclone Marcia was located at latitude 22.9°S and longitude 150.5°E which put it about 25 miles northwest of Yeppoon, about 85 miles northwest of Gladstone and about 340 miles north-northwest of Brisbane, Australia.  Marcia was moving toward the south at 12 m.p.h.  The maximum sustained wind speed was 110 m.p.h. and there were gusts to 150 m.p.h.  The minimum surface pressure was 948 mb.

Marcia is beginning to weaken.  It will initially weaken slowly because it is still near the ocean and the circulation has well developed upper level outflow.  As Marcia moves farther south, it will encounter more vertical wind shear.  Increased wind shear and more time over land, will speed up the rate of weakening in 12 to 24 hours.

Marcia is still strong enough to contain damaging winds.  The center of circulation will pass near Rockhampton in a few hours.  It could produce a significant storm surge on the portion of the coast where the winds are blowing toward the coastline.  Marcia could also generate locally heavy rainfall and the potential for flooding.

 

Tropical Cyclone Lam Moving Farther Inland and Weakening

Tropical Cyclone Lam made landfall earlier today just to the southwest of Elcho Island on the north coast of Australia.  Lam is continuing to move farther inland in the Northern Territory.  At 9:00 p.m. EST on Thursday the center of Lam was located at latitude 13.1°S and longitude 134.4°S which put it 40 miles north of Bulman and about 75 miles south-southwest of Milingimbi, Australia.  It was moving toward the southwest at 10 m.p.h.  The maximum sustained wind speed was 65 m.p.h. and there were gusts to 90 m.p.h.  The minimum surface pressure was 985 mb.

Lam will continue to weaken as it moves farther into the interior of Australia.  The weakening will occur slowly because the circulation is moving over relatively flat terrain.  Lam could produce locally heavy rainfall and the potential for flooding along its path.  The winds and waves along the coast should continue to lessen and the water levels should decrease.

Lam and Marcia Equivalent of Major Hurricanes As They Affect Australia

Both Severe Cyclone Lam and Severe Tropical Cyclone Marcia intensified rapidly during the past few hours and both storms are now the equivalent of major hurricanes.  Lam is making landfall on the north coast of Australia just to the southwest of Elcho Island.  The motion of Marcia has slowed, but it is approaching the coast of Queensland.

At 8:00 a.m. EST on Thursday the center of Lam was located at latitude 12.0°S and longitude 135.4°E which put it about 12 miles west-northwest of Galiwinku and about 35 miles east-northeast of Milingimbi, Australia.  Lam was moving toward the southwest at 5 m.p.h.  The maximum sustained wind speed was 115 m.p.h., which makes Lam the equivalent of a Category 3 hurricane on the Saffir-Simpson Scale.  It was estimate that there were wind gusts to 160 m.p.h. and the minimum surface pressure was 963 mb.

At 8:00 a.m. EST on Thursday the center of Marcia was located at latitude 20.8°S and longitude 150.6°S which put it about 150 miles east of Mackay and about 160 miles north of Yeppoon, Australia.  Lam was moving toward the west-southwest at 7 m.p.h.  The maximum sustained wind speed was 120 m.p.h., which makes Marcia the equivalent of a Category 3 hurricane on the Saffir-Simpson Scale.  It was estimated that there were wind gusts to 165 m.p.h. and the minimum surface pressure was 956 mb.

Both tropical cyclones are capable of causing significant wind damage.  They are also capable of generating a significant storm surge near where the center makes landfall.  Locally heavy rainfall and the potential for flooding exists, as the storms move inland.

 

Tropical Cyclone Marcia Intensifying Quickly as It Nears Australia

The circulation around Tropical Cyclone Marcia is organizing rapidly as it moves toward eastern Australia.  An eye is apparent on visible satellite imagery and Marcia rapidly intensified to hurricane intensity.  At 1:00 a.m. EST on Thursday the center of Marcia was located at latitude 20.5°S and longitude 151.0°E which put it about 125 miles east-northeast of Mackay and about 180 miles north-northeast of Yeppoon, Australia.  Marcia was moving toward the west-southwest at 16 m.p.h.  The maximum sustained wind speed was 95 m.p.h. and there were gusts to 135 m.p.h.  The minimum surface pressure was 956 mb.

Marcia has developed an eye and thunderstorms completely surround it.  The core of Marcia is symmetrical which indicates a well organized storm.  As Marcia moved toward the southwest, it moved west of the strongest upper level winds, which reduced the vertical wind shear.  Marcia was over warm Sea Surface Temperatures and the more favorable environment allowed it to intensify quickly.  It will remain in a favorable environment until it makes landfall and further intensification is possible.

Marcia is near the western end of a subtropical ridge which is steering it to the southwest.  Once the system moves inland, it is likely to move in more of a southerly direction, but it should be weaker by that time.

Marcia could make landfall in around 12 hours near the Northumberland Isles between Mackay and Yeppoon.  The rapid organization of the circulation increased the destructive potential of Marcia.  It is strong enough to cause wind damage and it could cause a storm surge near where the center makes landfall.  The stronger circulation could also produce locally heavy rainfall and the potential for flooding as it moves inland.

 

Severe Cyclone Lam Approaching North Coast of Australia

Severe Cyclone Lam is located just to the west of the Wessel Islands.  It is moving slowly southwestward toward the north coast of Australia.  At 10:00 p.m. EST on Wednesday the center of Severe Cyclone Lam was located at latitude 11.5°S and longitude 135.9°E which put it about 40 miles north-northeast of Elcho Island and about 75 miles northwest of Nhulunbuy, Australia.  Lam was moving toward the southwest at 5 m.p.h.  The maximum sustained wind speed was 85 m.p.h. and there were gusts to 120 m.p.h.  The minimum surface pressure was 967 mb.

Lam is moving over Sea Surface Temperatures that are warmer than 30°C.  The upper level winds are relatively light and there is little vertical wind shear.  Since the environment is favorable, some further intensification is possible before Lam makes landfall in about 12 hours.

Lam is expected to make landfall on the north coast of Australia just to the southwest of Elcho Island.  It is a strong tropical cyclone capable of causing wind damage.  A weather station near Cape Wessel measured a sustained wind speed of 80 m.p.h. and wind gusts to 100 m.p.h. when the eyewall passed over the station.  The intensity and slow movement of Lam are also creating the potential for a significant storm surge near where the center makes landfall.  The slow motion will also create the potential for locally heavy rainfall and flooding as Lam moves inland.

 

Severe Cyclone Lam Reaches Hurricane Intensity Near Wessel Islands

Tropical Cyclone Lam reached hurricane intensity near the northern coast of Australia and was upgraded to Severe Cyclone status.  At 10:00 p.m. EST on Tuesday the center of Severe Cyclone Lam was located at latitude 11.1°S and longitude 137.0°E which put it near the Wessel Islands, about 80 miles north of Nhulunbuy and about 110 miles northeast of Elcho Island, Australia.  Lam was moving toward the west at 8 m.p.h.  The maximum sustained wind speed was 75 m.p.h. and there were gusts to 100 m.p.h.  The minimum surface pressure was 976 mb.

Lam remains over very warm Sea Surface Temperatures and the vertical wind shear is modest.  So, it has the potential to intensify further as long as the center remains over water.  A subtropical ridge is steering Lam westward and that motion is expect to continue for another 8 to 16 hours.  When it reaches the western edge of the ridge, Lam is expected to turn toward the southwest and it could make a landfall west of Elcho Island in 24 to 36 hours.  Lam is strong enough to pose a risk of a significant storm surge and it could also produce locally heavy rainfall and flooding as it moves inland.