Tag Archives: Mauritius

Tropical Cyclone Enawo Forms North of La Reunion

Tropical Cyclone Enawo formed north of La Reunion on Friday.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Enawo was located at latitude 13.2°S and longitude 56.2°E which put it about 520 miles (835 km) north of St. Denis, La Reunion.  Enawo was moving toward the southwest at 4 m.p.h.  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 994 mb.

An area of low pressure organized slowly over the southwest Indian Ocean during the past few days.  Bands of thunderstorms formed west of the center of circulation and some of the bands began to wrap closer to the center on Friday.  The low pressure system exhibited the characteristic structure of a developing tropical cyclone and it was designated Tropical Cyclone Enawo.  Although there are more thunderstorms near the center of circulation, the distribution of the storms is still asymmetrical.  There are many more thunderstorms in the western half of the circulation.  The asymmetry probably indicates that some vertical wind shear is slowing the organization of the circulation.

Tropical Cyclone Enawo will be moving through an environment favorable for intensification during the next several days.  It will be moving over water where the Sea Surface Temperature is near 30°C.  Enawo is northwest of an upper level ridge which is generating easterly winds that are blowing toward the top of the circulation.  The upper level ridge could be the source of the vertical wind shear that is slowing the intensification of the tropical cyclone.  The upper level wind shear could decrease during the weekend and Tropical Cyclone Enawo is likely to intensify into the equivalent of a hurricane/typhoon.  Once an inner core become well established at the center of circulation, a period of rapid intensification may be possible.

A subtropical ridge located southeast of Enawo is steering the tropical cyclone toward the southwest.  Guidance from the numerical models is divergent about the future strength of the ridge.  Some of the models, like the Global Forecasting System,  are predicting a weaker ridge and turn Tropical Cyclone Enawo more toward the south.  Other models, such as the European Center for Medium Range Forecasting System model, strengthen the subtropical ridge and steer Tropical Cyclone Enawo west toward northeast Madagascar.  Given the uncertainty in both the track and intensity forecasts, interests in the southwest Indian Ocean should monitor Tropical Cyclone Enawo closely.

Tropical Cyclone Carlos Intensifies Southwest of La Reunion

Tropical Cyclone Carlos intensified on Wednesday as it moved farther southwest of La Reunion.  At 10:00 p.m. EST on Wednesday the center of Tropical Cyclone Carlos was located at latitude 23.9°S and longitude 53.4°E which put it about 240 miles (390 km) south-southwest of St. Denis, La Reunion.  Carlos was moving toward the southeast at 9 m.p.h. (15 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 989 mb.

Tropical Cyclone Carlos is more well organized than it has been during any part of its existence.  A ring of thunderstorms wraps nearly completely around a small eye at the center of circulation.  There is only a small break in the eyewall on the northwest side of the eye.  Several other bands of thunderstorms exist in the eastern half of the circulation.  There are far fewer thunderstorms in the western half of the circulation.  The thunderstorms in the eyewall are generating strong upper level divergence which is pumping out mass in all directions.  The well developed upper level divergence allowed the surface pressure to decrease and the winds increased in response to the lower central pressure.

Tropical Cyclone Carlos moved into an area where the upper level winds were not as strong and the vertical wind shear diminished.  Carlos is currently in an area where there is little vertical wind shear.  It is moving over water where the Sea Surface Temperature is near 28°C.  When the shear diminished the tropical cyclone was able to extract and to use the energy from the ocean more efficiently which allowed it to intensify.  Tropical Cyclone Carlos will continue to move through a favorable environment for another 24 to 36 hours.  It still has a chance to intensify into the equivalent of a hurricane/typhoon.  Eventually, when Tropical Cyclone Carlos moves to a higher latitude, it will move into an area of stronger upper level winds.  When that happens increased wind shear and cooler Sea Surface Temperatures will cause Tropical Cyclone Carlos to weaken.

Tropical Cyclone Carlos has reached the western end of a subtropical ridge.  The counterclockwise flow around the ridge is starting to steer Carlos toward the southeast.  A general southeasterly motion is expected to continue during the next several days.  On its anticipated track the core of Tropical Cyclone Carlos with the strongest winds is expected to pass south of La Reunion.

Tropical Cyclone Carlos Passing West of La Reunion

The core of Tropical Cyclone Carlos passed west of La Reunion on Tuesday.  At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Carlos was located at latitude 21.4°S and longitude 53.2°E which put it about 130 miles (210 km) west-southwest of St. Denis, La Reunion.  Carlos 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 1000 mb.

Limited thunderstorm formation and moderate vertical wind shear caused the low level circulation to weaken slightly on Tuesday.  A few more thunderstorms appeared to develop south of the center of circulation during the past few hours.  Additional thunderstorms seemed to be forming in spiral bands outside the core of the circulation.  The thunderstorms forming south of the core were generating upper level divergence which was pumping mass away from center of circulation,  So, after appearing less organized earlier in the day, the circulation of Tropical Cyclone Carlos seemed to be showing signs of greater organization in recent hours.

An upper level ridge east of Carlos is generating northeasterly winds that are blowing toward the top of the tropical cyclone.  Those winds are producing moderate vertical wind shear, which is inhibiting intensification.  However, Tropical Cyclone Carlos is moving over water where the Sea Surface Temperature is near 28°C.  So, there is plenty of energy in the upper ocean to support strengthening.  The upper level winds could diminish during the next 24 hours.  If the vertical wind shear decreases, then Tropical Cyclone Carlos could intensify during the next 24 to 36 hours.

Carlos is moving around the western end of a subtropical ridge which is steering the tropical cyclone toward the southwest.  Tropical Cyclone Carlos is expected to reach the western end of the ridge in 24 to 36 hours and then it will start to move toward the southeast.  On its anticipated track the core of Tropical Cyclone Carlos will move between La Reunion and Madagascar.  Tropical Cyclone Carlos is expected to pass south of La Reunion after it starts to move toward the southeast.

Tropical Cyclone Carlos brought locally heavy rain to portions of Mauritius and La Reunion.  Outer rainbands could bring some additional rain to parts of La Reunion during the next day or two.

Tropical Cyclone Carlos Weakens As It Passes Northwest of Mauritius

Tropical Cyclone Carlos weakened on Monday as it passed northwest of Mauritius.  At 10:00 p.m. EST on Monday the center of Tropical Cyclone Carlos was located at latitude 19.3°S and longitude 56.0°E which put it about 100 miles (160 km) northwest of Port Louis, Mauritius.  Carlos was moving toward the southwest at 10 m.p.h. (16 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 997 mb.

An upper level ridge centered northeast of Carlos generated northerly winds which created moderate vertical wind shear over the top of the tropical cyclone.  The upper level winds sheared the tops off many of the thunderstorms and created an asymmetrical distribution of the convection.  The strongest thunderstorms are currently in a short spiral band located southwest of the center of circulation.  Although there is a well defined low level circulation, the bands in other parts of Tropical Cyclone Carlos contain mostly showers and low clouds.  The thunderstorms in the short spiral band are generating some upper level divergence which is pumping out mass to the south of the tropical cyclone.

Tropical Cyclone Carlos is moving through an environment that is currently unfavorable for intensification.  However, the environment could become more favorable during the next day or two.  Tropical Cyclone Carlos will move over water where the Sea Surface Temperature is near 28°C.  The strength of the upper level winds could diminish during the next 24 to 48 hours.  If the vertical wind shear decreases, Tropical Cyclone Carlos could intensify before it moves over colder water later this week.  There is still a chance that Tropical Cyclone Carlos could reach hurricane intensity during the next day or two.

A subtropical ridge northeast of Carlos is steering the tropical cyclone toward the southwest.  That general motion is expected to continue for another 24 to 36 hours.  When Carlos reaches the southwestern end of the ridge, it is forecast to turn gradually toward the the southeast.  On its anticipated track the center of Tropical Cyclone Carlos is expected to pass northwest of Mauritius and La Reunion.  Tropical Cyclone Carlos brought locally heavy rain to parts of Mauritius.  Carlos could also bring gusty winds and locally heavy rain to parts of La Reunion.

Tropical Cyclone Carlos Stronger As It Meanders North of Mauritius

Tropical Cyclone Carlos strengthened on Sunday as it meandered slowly north of Mauritius.  At 10:00 p.m. EST on Sunday the center of Tropical Cyclone Carlos was located at latitude 18.0°S and longitude 57.9°E which put it about 160 miles (260 km) north-northeast of Port Louis, Mauritius.  Carlos was moving toward the east-southeast at 3 m.p.h. (5 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 987.

Although Tropical Cyclone Carlos strengthened on Sunday, the circulation is exhibiting some effects of vertical wind shear.  Thunderstorms dissipated north of the center of circulation and the strongest thunderstorms are currently forming south of the center.  A primary band of storms extends southeast of the center of circulation.  A new broken band of showers and thunderstorms is beginning to develop around the northern periphery of the circulation.  The thunderstorms south of the center are generating upper level divergence which is pumping out mass to the southeast of the tropical cyclone.

The environment around Tropical Cyclone Carlos has both favorable and unfavorable factors.  Carlos will be moving over water where the Sea Surface Temperature is near 28°C which means there is sufficient energy in the upper ocean.  However, an upper level ridge east of Tropical Cyclone Carlos is generating northwesterly winds which are blowing across the top of the circulation.  The upper level winds are generating moderate vertical wind shear which is inhibiting the development of thunderstorms northwest of the center.  The wind shear is contributing to the asymmetrical distribution of the storms around the tropical cyclone and it is inhibiting divergence to the west of Carlos.  If the wind shear continues, it will continue to inhibit intensification.  Tropical Cyclone Carlos does have a very well organized low level circulation and it could intensify if the wind shear decreases.

The steering currents around Tropical Cyclone Carlos are weak, which is why it has not moved much during the past 24 hours.  A subtropical ridge east of Carlos is forecast to strengthen and the ridge is likely to steer the tropical cyclone more toward the southwest during the next day or two.  On its anticipated track the center of Tropical Cyclone Carlos could be near Mauritius in about 24 hours.  Carlos could be approaching La Reunion in 36 hours.  Tropical Cyclone Carlos could be the equivalent of a strong tropical storm or a hurricane when it approaches Mauritius and La Reunion.  Carlos could bring gusty winds and locally heavy rain to those locations.

Tropical Cyclone Carlos Strengthens North of Mauritius

Tropical Cyclone Carlos strengthened on Saturday as it moved north of Mauritius and La Reunion.  At 10:00 p.m. EST on Saturday the center of Tropical Cyclone Carlos was located at latitude 17.5°S and longitude 56.7°E which put it about 190 miles (310 km) north-northwest of Port Louis, Mauritius.  Carlos was moving toward the south at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 995 mb.

The circulation of Tropical Cyclone Carlos was asymmetrical for much of Saturday, but more thunderstorms formed close to the center of circulation during the past few hours.  There is a small circular clear area at the center of circulation which could indicate the formation of an eye.  Strong thunderstorms are building in a circular ring around the clear area.  The strongest winds are occurring in those thunderstorms.  There are additional showers and thunderstorms developing in bands in the eastern half of the circulation.  Few thunderstorms are forming in the western half of the circulation.  The thunderstorms around core of the circulation are generating upper level divergence which is pumping out mass.

Tropical Cyclone Carlos is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 28.5°C.  The upper level winds are weak and there is little vertical wind shear.  Carlos is likely to strengthen and there could be a period of rapid intensification if the inner core consolidates around and eye.  Tropical Cyclone Carlos is likely to intensify into the equivalent of a hurricane during the next several days.

Carlos is moving around the western end of a subtropical ridge which is steering the tropical cyclone slowly southward.  A general southward motion is expected to continue for another day or two.  After that time the subtropical ridge is expected to strengthen and steer Tropical Cyclone Carlos more toward the southwest.  On its anticipated track the center of Tropical Cyclone Carlos could be approaching Mauritius and La Reunion in 36 to 48 hours.  Even if the center passes northwest of those locations, Tropical Cyclone Carlos could come close enough to bring gusty winds and locally heavy rainfall.

Tropical Cyclone Organizing Over Southwest Indian Ocean

A tropical cyclone organized north of La Reunion and east of Madagascar over the Southwest Indian Ocean on Friday.  At 1:00 p.m. EST on Friday the center of the tropical cyclone was located at latitude 14.5°N and longitude 56.1°E, which put it about 435 miles (700 km) north of La Reunion.  The tropical cyclone was moving toward the south at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1002 mb.

An area of showers and thunderstorms persisted north of La Reunion for much of the past week.  Curved bands of showers and thunderstorms began to develop on Friday and the circulation took on more of a circular shape.  Thunderstorms near the center of the circulation began to generate upper level divergence which was pumping out mass and the surface pressure started to decrease.  There is a distinct center in the low level circulation and the tropical cyclone would be the equivalent of a tropical depression if it were over the Atlantic or Pacific Oceans.

The environment surrounding the tropical cyclone is favorable for further intensification.  The tropical cyclone is over water where the Sea Surface temperature is around 28.5°C.  So, there is plenty of energy in the upper ocean.  The upper level winds over the tropical cyclone are light and there is little vertical wind shear.  The absence of vertical wind shear is allowing the upper level divergence to pump out mass in all directions.  The tropical cyclone is expected to strengthen during the next 24 hours and it could intensify quickly if the inner core continues to develop.

The winds at the steering level are weak, which is why the system did not move much during the past few days.  Weak northerly winds could push the tropical cyclone slowly toward the south toward Mauritius and La Reunion.  The tropical cyclone could be near those islands in about three or four days.

Tropical Cyclone Abela Forms over the South Indian Ocean in the Middle of Winter

Tropical Cyclone Abela formed over the South Indian Ocean in the middle of winter on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Cyclone Abela was located at latitude 12.9°S and longitude 62.4°E which put it about 640 miles (1030 km) northeast of Port Louis, Mauritius.  Abela was moving toward the west-southwest at 18 m.p.h. (29 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 989 mb.

Enough spiral banding developed in a low pressure system over the South Indian Ocean to allow the system to be classified as Tropical Cyclone Abela.  The circulation is not well organized.  Most of the thunderstorms were located in a thin primary rainband that wrapped around the western side of the center of circulation.  The other rainbands contained shallower clouds.  There was enough convection to produce some upper level divergence.  Winds to tropical storm force extend out about 150 miles (240 km) from the center of circulation.

The environment around Tropical Cyclone Abela is only marginal for further intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 26°C.  Northeasterly winds in the upper levels are creating a moderate amount of vertical wind shear.  The wind shear will limit the potential for intensification during the short term.  In about a day or so Abela will move over cooler SSTs and it should start to weaken.

A ridge of high pressure located east of Abela is steering the tropical cyclone toward the west-southwest and that general motion is expected to continue for another day or two.  On its anticipated track Tropical Cyclone Abela will pass north of Mauritius and La Reunion.  Abela is expected to reach the western end of the ridge and recurve toward the south as it nears the east coast of Madagascar.

Tropical Cyclone Fantala Weakens Northeast of Madagascar

Thunderstorms near the center of Tropical Cyclone Fantala dissipated and it weakened as moved northeast of Madagascar.  At 5:00 p.m. EDT  on Saturday the center of Tropical Cyclone Fantala was located at latitude 11.5°S and longitude 54.5°E which put it about 350 miles (565 km) east of Antsirañana, Madagascar.  Fantala was moving west-northwest at 10 m.p.h. (16 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 988 mb.

Tropical Cyclone Fantala reversed course again on Saturday and it is moving over the same part of the South Indian Ocean that it already crossed twice during the past few days.  The winds produced by Fantala mixed cooler water up to to the surface of the ocean during its previous passages over the same region.  The cooler water means that there is less energy available to power the circulation of Tropical Cyclone.  Although the winds continue to rotate around the center of circulation, there are no thunderstorms near the core of Fantala.  There are still several thunderstorms in rainbands farther to the east of the center of circulation.

If new thunderstorms do not develop around the core of the circulation, the winds will gradually spin down and the tropical cyclone will dissipate within a few days.  Upper level winds blowing from the west-northwest are also generating some vertical wind shear, which will make it more difficult for new thunderstorms to form.

A subtropical ridge southwest of Fantala is steering the tropical cyclone toward the west-northwest and that general motion is expected to continue for the next several days.  On its anticipated track Tropical Cyclone Fantala is forecast to pass north of Madagascar and move over the Seychelles.  It could be even weaker by the time it gets to the Seychelles.

Tropical Cyclone Fantala Stalls East of Madagascar

Tropical Cyclone Fantala moved into an area of weaker steering currents on Thursday and it stalled about 500 miles (800 km) east of northern Madagascar.  At 5:00 p.m. EDT on Thursday the center of Tropical Cyclone Fantala was located at latitude 13.0°S and longitude 56.7°E which put it about 515 miles (830 km) east of Antsirañana, Madagascar.  Fantala was moving toward the southeast at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 95 m.p.h. (155 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 963 mb.

Although Fantala weakened slightly on Thursday, the structure of the inner core of the circulation remained fairly intact.  A thin ring of thunderstorms was wrapped around an that was obscured on conventional satellite imagery.  Other bands of thunderstorms spiraled around the eyewall.  The thunderstorms in the core of Fantala were generating upper level divergence to the north and east of the center of circulation.  It appears that drier air may be getting pulled into the eastern portion of the circulation outside the core of Fantala.  There only only isolated thunderstorms in the rainbands in that part of the circulation.

The environment is marginally favorable for intensification.  The upper level winds are light enough so there is only a moderate amount of vertical wind shear.  Fantala is over water where the Sea Surface Temperature is near 29°C.  However, because Fantala is moving so slowly, it could mix cooler water to the surface which would reduce the energy available to the tropical cyclone.  In addition the drier air will also limit the supply of energy being transported into the core of the circulation.

Tropical Cyclone Fantala has moved into an area where the steering currents are weak.  It may not move much during the next 24 hours.  A subtropical ridge is forecast to develop southwest of Fantala in a day or two.  When the subtropical ridge develops, it is expected to steer Fantala back toward the west again.  On its anticipated track Tropical Cyclone Fantala could be approaching the northern part of Madagascar in 60 to 72 hours.