Monthly Archives: January 2018

Tropical Cyclone Fehi Develops Near New Caledonia

Tropical Cyclone Fehi developed over the Coral Sea near New Caledonia on Sunday.  At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Fehi was located at latitude 19.7°S and longitude 162.2°E which put it about 360 miles (580 km) northwest of Noumea, New Caledonia.  Fehi was moving toward the south-southeast at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 60 m.p.h. (90 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 982 mb.

The circulation of Tropical Cyclone Fehi was not well organized for much of Sunday, but it exhibited signs of greater organization in recent hours.  An upper level low near eastern Australia was producing strong northwesterly winds that were blowing over the top of the circulation.  Those winds caused strong vertical wind shear for much of Sunday, but the shear appeared to decrease on Sunday night.  A distinct low level center of circulation was exposed on recent visible satellite images.  Most of the thunderstorms were occurring in bands south of the center of circulation.  More bands of showers and low clouds seemed to be forming in the northern half of the circulation.  A rainband appeared to be wrapping around the northern side of the circulation.  There was some upper level divergence to the southeast of Tropical Cyclone Fehi.

Tropical Cyclone Fehi will be moving through an environment that will be marginally favorable for intensification during the next day or two.  Fehi is moving over water where the Sea Surface Temperature is near 28°C.  The upper level low will continue to cause vertical wind shear, but the shear may be small enough to allow for intensification.  Tropical Cyclone Fehi could intensify during the next 24 hours.  When Fehi moves farther south, it will move over much cooler water and the tropical cyclone will start to weaken.  Tropical Cyclone Fehi could make a transition to an extratropical cyclone in two or three days.

The upper low near eastern Australia is steering Tropical Cyclone Fehi toward the south-southeast.  A general motion toward the southeast is expected during the next two or three days.  On its anticipated track the center of Tropical Cyclone Fehi is forecast to pass west of New Caledonia.  Although the center is likely to pass to the west of New Caledonia, rainbands on the eastern side of Fehi could bring gusty winds and locally heavy rain.  Heavy could cause flash floods.  Tropical Cyclone Fehi could approach New Zealand in about three days.  Fehi could be a strong extratropical cyclone at that time.

Tropical Cyclone Cebile Intensifies Rapidly Into Equivalent of Major Hurricane

Tropical Cyclone Cebile intensified rapidly on Sunday from a tropical storm to the equivalent of a major hurricane over the South Indian Ocean.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Cebile was located at latitude 14.5°S and longitude 82.5°E which put it about 850 miles (1375 km) southeast of Diego Garcia.  Cebile was moving toward the southwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 945 mb.

Tropical Cyclone Cebile intensified very rapidly during the past 24 hours as it moved through a very favorable environment.  The maximum sustained wind speed increased from 50 m.p.h. (80 km/h) to 130 m.p.h. (215 km/h).  The circulation of Tropical Cyclone Cebile is very well organized.  There is a circular eye at the center of circulation.  The eye is surround by a ring of strong thunderstorms and the strongest winds are occurring in the ring of storms.  Rainbands are revolving around the core of the circulation.  Tropical Cyclone Cebile is generating strong upper level divergence which is pumping away mass and allowing the surface pressure to decrease rapidly.

The circulation of Tropical Cyclone Cebile is symmetrical.  Winds to hurricane/typhoon force extend out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extend out about 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Cebile is 25.1.  The Hurricane Size Index (HSI) is 12.7 and the Hurricane Wind Intensity Size Index (HWISI) is 37.8.

Tropical Cyclone Cebile continues to move through an environment favorable for intensification.  Cebile is moving over water where the Sea Surface Temperature is near 28°C.  The upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Cebile is likely to intensify further and it could become the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale.

Cebile is moving near the western part of a subtropical ridge which is steering the tropical cyclone toward the southwest.  A general southwesterly motion is expected to continue for the next few days.  On its anticipated track Tropical Cyclone Cebile will remain well south of Diego Garcia.

Elsewhere in the tropics, Tropical Cyclone 08S was moving near the northern end of New Caledonia.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone 08S was located at latitude 18.8°S and longitude 162.1°E which put it about 370 miles (600 km) northwest of Noumea, New Caledonia.  It was moving toward the southeast at 11 m.p.h. (17 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 986 mb.

Tropical Cyclone Cebile Forms East of Diego Garcia

After a relatively quiet week in the tropics Tropical Cyclone Cebile formed east of Diego Garcia on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Cebile was located at latitude 12.1°S and longitude 84.2°E which put it about 870 miles (1405 km) east-southeast of Diego Garcia.  Cebile was moving toward the southwest at 7 m.p.h. (11 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 998 mb.

Tropical Cyclone Cebile organized rapidly on Saturday.  A primary rainband wrapped most of the way around the center of circulation and an elliptical eye appeared to be developing at the center.  Other bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Cebile.  There were more thunderstorms in the western half of the circulation, but there were rainbands in all quadrants of Cebile.  Storms in the core of the circulation were generating upper level divergence which was pumping mass away from the tropical cyclone.  The removal of mass was causing the surface pressure to decrease and the wind speed to increase.

Tropical Cyclone Cebile will move through an environment favorable for intensification.  It will move over water where the Sea Surface Temperature is near 28°C.  Cebile is moving just to the north of the axis of a subtropical ridge that runs east to west across the Southern Indian Ocean.  The northern half of the ridge is producing easterly winds which are blowing toward the top of the circulation, but the vertical wind shear is not too strong.  A combination of warm water and minimal vertical wind shear will allow Tropical Cyclone Cebile to strengthen and it could intensify rapidly.  Cebile is likely to strengthen into the equivalent of a hurricane/typhoon during the next day or two.  Tropical Cyclone Cebile could intensify into the equivalent of a major hurricane during the next week.

The subtropical ridge is steering Tropical Cyclone Cebile toward the southwest and that general motion is expected to continue for several more days.  On its anticipated track Tropical Cyclone Cebile is expected to move southeast of Diego Garcia.

Tropical Cyclone Berguitta Speeds Past La Reunion

Tropical Cyclone Berguitta sped past La Reunion on Thursday.  At 4:00 p.m. EST on Thursday the center of Tropical Cyclone Berguitta was located at latitude 22.8°S and longitude 54.3°E which put it about 70 miles (110 km) southwest of La Reunion.  Berguitta was moving toward the west-southwest at 22 m.p.h. (35 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 982 mb.

Tropical Cyclone Berguitta was the equivalent of a hurricane/typhoon when it moved past La Reunion.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of circulation.  So, parts of La Reunion may have experienced winds to hurricane/typhoon force.  Winds to tropical storm force extended out about 230 miles (370 km) from the center.  Winds to tropical storm force would have occurred over all of La Reunion.  Berguitta also dropped locally heavy rain over La Reunion and flooding is a possibility.

Tropical Cyclone Berguitta will move into an environment that will become increasingly less favorable for a tropical cyclone as it moves away from La Reunion.  Berguitta is moving over water where the Sea Surface Temperature is near 26°C, but it will move over colder water when it moves farther south.  An upper level trough west of Madagascar will produce northwesterly winds which will increase the vertical wind shear.  A combination of colder water and increased shear will slowly weaken Tropical Cyclone Berguitta.  Berguitta will likely make a transition to an extratropical cyclone during the weekend.

Berguitta is moving around the western end of a subtropical ridge, which is steering the tropical cyclone toward the southwest.  It is expected to continue to move toward the southwest for another day or so.  At that time Berguitta will move around the western end of the ridge and it will move more toward the south.  On its anticipated track the center of Tropical Cyclone Berguitta is expected move steadily away from La Reunion.  Berguitta is forecast to stay east of Madagascar.  Weather conditions on La Reunion should gradually improve as Tropical Cyclone Berguitta moves away.

Tropical Cyclone Berguitta Brings Wind, Rain to Mauritius & La Reunion

Tropical Cyclone Berguitta was bringing wind and rain to Mauritius and La Reunion late Wednesday as it closed in on those places.  At 10:00 p.m. EST on Monday the center of Tropical Cyclone Berguitta was located at latitude 20.1°S and longitude 58.0°E which put it about 80 miles (130 km) east-northeast of Port Louis, Mauritius.  Berguitta was moving toward the southwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 979 mb.

Tropical Cyclone Berguitta was the equivalent of a hurricane/typhoon as it approached Mauritius and La Reunion.  A partial eyewall surrounded the remnant of the eye.  A primary rainband wrapped around the western side of the circulation.  The heaviest rain was falling in the rainband.  Numerous bands of showers and isolated thunderstorms were revolving around the core of the circulation.  Tropical Cyclone Berguitta was still generating upper level divergence which was pumping mass away from the center of circulation.  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 195 miles (315 km) from the center.

Tropical Cyclone Berguitta was moving through an environment that could allow it to maintain its intensity for another 24 to 36 hours.  Berguitta will move over water where the Sea Surface Temperature is near 27°C.  An upper level ridge to the east of Berguitta is producing easterly winds which are blowing toward the top of the tropical cyclone.  Those winds are causing moderate vertical wind shear, but they may not be strong enough to weaken the storm during the next 24 hours.

Tropical Cyclone Berguitta is moving around the western end of a subtropical ridge which is steering the tropical cyclone toward the southwest.  A general southwesterly motion is expected to continue for another day or two.  On its anticipated track the center of Tropical Cyclone Berguitta will reach Mauritius within six hours.  The center of Berguitta will be near La Reunion in 12 to 14 hours.

Tropical Cyclone Berguitta will bring strong, gusty winds to Mauritius and La Reunion on Thursday.  It could be the equivalent of a hurricane/typhoon when it moves over those places.  The center could pass right over Mauritius and the winds to hurricane/typhoon force could blow over it.  The center could pass just to the east of La Reunion, but winds to hurricane/typhoon force could also blow across it.  Berguitta will also drop locally heavy rain which could cause floods.  The winds could cause a storm surge of 5 to 8 feet (1.5 to 1.5 meters) on the eastern shores where the winds will be blowing water toward the coast.

Tropical Cyclone Berguitta Moves Closer to Mauritius

Tropical Cyclone Berguitta moved closer to Mauritius and La Reunion on Tuesday.  At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Berguitta was located at latitude 18.4°S and longitude 60.3°E which put it about 250 miles (400 km) east-northeast of Port Louis, Mauritius.  Berguitta was moving toward the southwest at 4 m.p.h. (6 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 973 mb.

Tropical Cyclone Berguitta weakened a little on Tuesday but it remained a dangerous tropical cyclone.  An upper level ridge southeast of Berguitta produced easterly winds which caused some vertical wind shear over the tropical cyclone.  Satellite imagery also suggested that Berguitta could have gone through an eyewall replacement cycle.  The combination of increased wind shear and a possible eyewall replacement cycle altered the structure of Berguitta.  Microwave satellite images intermittently indicated the presence of an eye at the center of circulation.  However, almost all of the stronger thunderstorms were occurring west of the center of circulation.  The bands in the eastern half of the circulation consisted primarily of low clouds and showers.  The increased shear probably caused the asymmetrical distribution of storms.

Berguitta will move through an environment supportive of a tropical cyclone during the next 24 hours.  It will move over water where the Sea Surface Temperature is near 28°C.  The upper level ridge will continue to produce vertical wind shear.  The wind shear will likely prevent Berguitta from intensifying significantly.  Tropical Cyclone Berguitta is forecast to weaken slowly during the next 24 hours, but it could maintain most of its intensity, since it is still over warm water.

Tropical Cyclone Berguitta is moving around the western end of a subtropical ridge which is steering the tropical cyclone toward the southwest.  A general southwesterly motion is forecast to continue for another day or two.  On its anticipated track the center of Tropical Cyclone Berguitta could reach Mauritius in 24 hours.  Berguitta is likely to be the equivalent of a hurricane/typhoon when it reaches Mauritius.  It will bring strong winds and locally heavy rain.  Heavy rain could cause serious flooding.  The strong winds could generate a storm surge of 4 to 7 feet (1 to 2 meters) at the coast.  Tropical Cyclone Berguitta could reach La Reunion within 36 hours.

Tropical Cyclone Berguitta Equivalent of a Major Hurricane

Tropical Cyclone Berguitta strengthened into the equivalent of a major hurricane on Monday as it moved over the South Indian Ocean.  At 4:00 p.m. EST on Monday the center of Tropical Cyclone Berguitta was located at latitude 18.1°S and longitude 62.4°E which put it about 375 miles (600 km) east-northeast of Port Louis, Mauritius.  Berguitta was moving toward the southwest at 5 m.p.h. (8 km/h).  The maximum sustained wind speed is 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (230 km/h).  The minimum surface pressure was 949 mb.

Tropical Cyclone Berguitta quickly intensified into the equivalent of a major hurricane on Monday.  A well formed circular eye developed at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in the ring.  Several bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the center of Berguitta were generating upper level divergence which was pumping large quantities of 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 extend out about 215 miles (345 km) from the center.

Tropical Cyclone Berguitta will move through an environment supportive of a strong tropical cyclone for several more days.  Berguitta will move over water where the Sea Surface Temperature is near 28°C.  It is moving through a region where the upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Berguitta is likely to maintain its intensity as the equivalent of a major hurricane and it could intensify further during the next day or two.

Tropical Cyclone Berguitta is moving near the western end of a subtropical ridge which is steering the tropical cyclone toward the southwest.  A general motion toward the southwest is forecast to continue for two or three more days.  On its anticipated track the center of Tropical Cyclone Berguitta could reach Mauritius within 48 hours.  Berguitta could reach La Reunion in less than 72 hours.

Tropical Cyclone Berguitta is a dangerous storm.  The Hurricane Intensity Index (HII) for Tropical Cyclone Berguitta is 20.6.  The Hurricane Size Index (HSI) is 14.1 and the Hurricane Wind Intensity Size Index (HWISI) is 34.7.  Those indices indicate that Tropical Cyclone Berguitta is capable of causing regional major damage.  Berguitta will bring strong winds and locally heavy rain to Mauritius and La Reunion.  The heavy rain is likely to cause flooding  and Berguitta could generate a storm surge at the coast.

Tropical Cyclone Berguitta Intensifies Into Equivalent of a Hurricane

Tropical Cyclone Berguitta intensified into the equivalent of a hurricane/typhoon on Sunday.  At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Berguitta was located at latitude 17.8°S and longitude 63.1°E which put it about 415 miles (670 km) east-northeast of Port Louis, Mauritius.  Berguitta was nearly stationary.  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 985 mb.

The circulation of Tropical Cyclone Berguitta continued to get better organized on Sunday.  An eye appeared intermittently at the center of circulation.  The eye was surrounded by an elliptical ring of thunderstorms and the strongest winds were occurring in those storms.  Bands of showers and thunderstorms were revolving around the core of the circulation.  Storms near the center of Berguitta were generating upper level divergence which was pumping mass away from the center of circulation.

Tropical Cyclone Berguitta will continue to move through an environment favorable for intensification during the next several days.  Berguitta will move over water where the Sea Surface Temperature is near 28°C.  The upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Berguitta will continue to strengthen and it could intensify into the equivalent of a major hurricane.

Tropical Cyclone Berguitta is moving in a region where the steering winds are weak.  Berguitta moved little on Sunday.  A subtropical ridge south of Berguitta is forecast to steer the tropical cyclone slowly westward during the next 24 to 48 hours.  Berguitta will near the western end of the ridge in about two days and it is likely to move toward the southwest after that time.  On its anticipated track Tropical Cyclone Berguitta could reach Mauritius within 72 hours.

The core of Tropical Cyclone Berguitta could move very close to Mauritius and La Reunion.  Berguitta could be the equivalent of a major hurricane at that time.  It has the potential to cause major wind damage, a storm surge, heavy rain and floods.

Elsewhere over the South Indian Ocean microwave images of Invest 99S depicted a structure that looked very much like a tropical cyclone.  At 10:00 p.m. EST on Sunday the center of Invest 99S was centered at latitude 15.1°S and longitude 41.6°E which put it about 75 miles (120 km) east of Lumbo, Mozambique.  Microwave satellite images showed a clear area at the center of circulation surrounded by broken ring of showers and thunderstorms.  A primary rainband wrapped around the eastern side of the circulation and secondary bands of showers and thunderstorms existed in all quadrants of the circulation.  However, no official government agency is classifying the system as a tropical cyclone at the current time.

Tropical Cyclone Berguitta Strengthens Over South Indian Ocean

Tropical Cyclone Berguitta strengthened over the South Indian Ocean on Saturday.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Berguitta was located at latitude 18.2°S and longitude 63.3°E which put it about 420 miles (675 km) east-northeast of Port Louis, Mauritius.  Berguitta was moving toward the west at 5 m.p.h. (8 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 994 mb.

The structure of Tropical Cyclone Berguitta organized quickly on Saturday.  An eye appeared on microwave satellite images of the center of circulation.  An elliptical ring of showers and thunderstorms surrounded the eye.  Several bands of showers and thunderstorms were revolving around the core of Tropical Cyclone Berguitta.  There were more thunderstorms south and east of the center of circulation.  Storms near the core of Berguitta were generating upper level divergence which was pumping away mass.  The removal of mass allowed the surface pressure to decrease and the winds speeds to increase.

Tropical Cyclone Berguitta will be moving through an environment favorable for intensification during the next several days.  Berguitta will move over water where the Sea Surface Temperature is near 28°C.  It will move through an area where the upper level winds are weak and there is little vertical wind shear.  Tropical Cyclone Berguitta will likely intensify into the equivalent of a hurricane/typhoon during the next 24 hours.  It could intensify more rapidly once the eye and inner core become fully organized.

A subtropical ridge south of Berguitta is steering the tropical cyclone slowly toward the west.  A general motion toward the west is expected during the next day or two.  In about 48 hours Tropical Cyclone Berguitta will be closer to the western end of the ridge and it could start to move more toward the southwest.  On its anticipated track Tropical Cyclone Berguitta could approach Mauritius and La Reunion in three or four days.  Berguitta could be the equivalent of a hurricane/typhoon at that time.

Elsewhere in the southern hemisphere former Tropical Cyclone Joyce continued to drop locally heavy rain over parts of Western Australia.  At 10:00 p.m. EST on Saturday the center of former Tropical Cyclone Joyce was located at latitude 25.4°S and longitude 115.6°E which put it about 35 miles (55 km) southeast of Gascoyne Junction.  Former Tropical Cyclone Joyce was moving toward the west-southwest at 8 m.p.h. (13 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 998 mb.  The locally heavy rain was creating the potential for flooding in some locations.

Tropical Cyclone Joyce Brings Wind and Rain to Western Australia

Tropical Cyclone Joyce brought wind and rain to Western Australia on Thursday.  At 10:00 p.m. EST on Thursday the center of Tropical Cyclone Joyce was located at latitude 19.6°S and longitude 120.9°E which put it about 20 miles (35 km) northeast of Wallal Downs, Australia.  Joyce was moving toward the southwest at 7 m.p.h. (11 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 989 mb.

The center of Tropical Cyclone Joyce moved along the coast of Western Australia from Bidyadanga toward Wallal Downs on Thursday.  Tropical Cyclone Joyce brought gusty winds up to 60 m.p.h. (95 km/h) to portions of the coast.  The fact that almost half the circulation of Joyce was flowing over land kept the tropical cyclone from intensifying significantly.  Several bands of showers and thunderstorms were occurring in the southwestern half of the circulation.  Fewer showers and thunderstorms were in the northeastern half of Tropical Cyclone Joyce, except for a couple of small bands in the periphery of the circulation near Cape Leveque.

Tropical Cyclone Joyce is being steered toward the southwest by a subtropical ridge and that motion is expected to continue for several more days.  On its anticipated track the center of Joyce will move inland near Wallal Downs.  It will continue inland on Friday and the center will pass near Shay Gap and Marble Bar.  A Tropical Cyclone Warning is in effect for the portion of the coast from Bidyadanga to De Grey.  Tropical Cyclone Joyce will gradually weaken when it moves inland, but it will continue to drop locally heavy rain over parts of Western Australia when it moves inland.  The Australian Bureau of Meteorology has issued Flood Warnings and Watches for portions of Western Australia.