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Tropical Cyclone Herold Brings Wind, Rain to Rodrigues

Tropical Cyclone Herold brought wind and rain to Rodrigues on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Tropical Cyclone Herold was located at latitude 21.4°S and longitude 64.1°E which put it about 125 miles (200 km) south-southeast of Port Mathurin, Mauritius.  Herold was moving toward the southeast at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 978 mb.

The core of Tropical Cyclone Herold passed west of Rodrigues on Tuesday, but it came close enough to that island to bring gusty winds and locally heavy rain.  A weather station at the Plaine Corail airport on Rodrigues reported a wind gust of 80 m.p.h. (130 km/h).

Although Tropical Cyclone Herold began to weaken on Tuesday.  It remained strong enough to generate wind gusts to hurricane/typhoon force over parts of Rodrigues.  Microwave satellite imagery indicated the there was still an eye at the center of Herold, although the eye was not evident on conventional infrared images.  The eye was surround by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Winds to hurricane/typhoon force extended out 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.

Tropical Cyclone Herold will continue to weaken during the next several days.  An upper level trough near Madagascar and an upper level ridge over the South Indian Ocean will interact to produce strong northwesterly winds which will blow toward the top of Herold.  Those winds will cause strong vertical wind shear and they will cause the tropical cyclone to weaken.

The upper level trough and ridge will steer Tropical Cyclone Herold toward the southeast.  On its anticipated track Herold will move quickly away from Rodrigues.  Weather conditions on that island will gradually improve as Tropical Cyclone Herold moves farther away.

Tropical Cyclone Herold Passes North of Mauritius

Tropical Cyclone Herold passed north of Mauritius on Monday.  At 5:00 p.m. EDT on Monday the center of Tropical Cyclone Herold was located at latitude 17.3°S and longitude 57.6°E which put it about 230 miles (370 km) north of Port Louis, Mauritius.  Herold was moving toward the east-southeast at 20 m.p.h. (32 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 972 mb.

The circulation around Tropical Cyclone Herold remained well organized on Monday.  Microwave satellite imagery indicated that there was an eye at the center of circulation, but the eye was not visible on conventional satellite images.  The eye was surround by a narrow ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Herold.  Many of the stronger thunderstorms were in bands south and east of the center of circulation.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center.  Winds to tropical storm force extended out 130 miles (215 km) from the center of circulation.

Tropical Cyclone Herold may have reached its maximum intensity.  Herold will move over water where the Sea Surface Temperature is near 28°C.  So, there will be plenty of energy in the upper layer of the South Indian Ocean to support intensification.  However, an upper level trough near Madagascar and an upper level ridge over the South Indian Ocean will interact to produce strong northwesterly winds which will blow toward the top of Tropical Cyclone Herold.  Those winds will cause moderate vertical wind shear and they will likely prevent further intensification.  In fact the wind shear is likely to be strong enough to cause Herold to start to weaken during the next 24 hours.

The upper level trough and ridge will combine to steer Tropical Cyclone Herold quickly toward the east-southeast.  On its anticipated track Herold could reach Rodrigues within 24 hours.  Tropical Cyclone Herold is likely to bring gusty winds and locally heavy rain to Port Mathurin and the rest of Rodrigues.  Heavy rain could cause flash floods in some locations.

Tropical Cyclone Gretel Speeds By New Caledonia

Tropical Cyclone Gretel sped by New Caledonia on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Cyclone Gretel was located at latitude 25.9°S and longitude 169.4°E which put it about 750 miles (1210 km) north-northwest of Auckland, New Zealand.  Gretel was moving toward the southeast at 37 m.p.h. (60 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 983 mb.

Tropical Cyclone Gretel moved around the western end of high pressure system over the South Pacific Ocean.  The high steered Gretel rapidly toward the southeast and the tropical cyclone sped over the Coral Sea west of New Caledonia.  Rainbands on the eastern side of Tropical Cyclone Gretel brought wind and rain to portions of New Caledonia on Sunday.

An upper level ridge produced strong northwesterly winds which created strong vertical wind shear.  The wind shear tilted the circulation around Tropical Cyclone Gretel toward the southeast and Gretel began to weaken.  The stronger thunderstorms were occurring in bands south and east of the center of Gretel.  Bands in other parts of the tropical cyclone consisted primarily of showers and lower clouds.  The wind field around Gretel expanded when the tropical cyclone started to weaken.  Winds to tropical storm force extended out 250 miles (400 km) from the center of circulation.

Tropical Cyclone Gretel will continue to move rapidly toward the southeast during the next several days.  On its anticipated track Gretel could pass north of New Zealand in 24 to 36 hours.

Elsewhere, over the South Indian Ocean Tropical Cyclone Herold strengthened east of Madagascar.  At 5:00 p.m EDT on Sunday the center of Tropical Cyclone Herold was located at latitude 15.5°S and longitude 53.2°E which put it about 405 miles (655 km) west-northwest of Port Louis, Mauritius.  Herold was moving toward the east-southeast at 7 m.p.h. (11 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 972 mb.  Tropical Cyclone Herold could reach Rodrigues in about 48 hours.

Tropical Cyclone Herold Drops Heavy Rain Over Northeast Madagascar

Tropical Cyclone Herold dropped heavy rain over parts of northeast Madagascar on Saturday.  A rainband on the western side of Herold was dropping locally heavy rain over northern Madagascar from Mananara to Iharana.  At 5:00 p.m. EST on Saturday the center of Tropical Cyclone Herold was located at latitude 15.0°S and longitude 51.2°E which put it about 545 miles (880 km) northwest of Port Louis, Mauritius.  Herold was moving toward the east at 1 m.p.h. (2 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 981 mb.

Tropical Cyclone Herold strengthened into the equivalent of a hurricane/typhoon on Saturday.  A large ragged circular eye with a diameter of 50 miles (80 km) formed at the center of Herold.  A broken ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  One strong band of showers and thunderstorms wrapped around the eastern and southern sides of Tropical Cyclone Herold.  A second strong band of showers and thunderstorms wrapped around the western and northern sides of Herold.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out 85 miles from the center.

Tropical Cyclone Herold will move through an environment favorable for intensification during the next 48 hours.  Herold will move over water where the Sea Surface Temperature is near 29°C.  It will move under an upper level ridge where the winds are weak and there will be little vertical wind shear.  Tropical Cyclone Herold will intensify during the next 48 hours and it could strengthen into the equivalent of a major hurricane.

Tropical Cyclone Herold has been in an area where the steering winds are weak and it has not moved very far during the past 24 hours.  A subtropical high pressure system over the South Indian Ocean will strengthen.  Herold will move around the southwestern part of the high pressure system and the high will steer the tropical cyclone toward the east-southeast.  On its anticipated track Tropical Cyclone Herold will move away from Madagascar on Sunday.  The center of Herold could pass north of Mauritius in three days.  Tropical Cyclone Herold could approach Rodrigues in 84 to 90 hours.

Tropical Cyclone Herold Forms East of Madagascar

Tropical Cyclone Herold formed over the South Indian Ocean east of Madagascar on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Herold was located at latitude 14.8°S and longitude 51.9°E which put it about 510 miles (825 km) northwest of Port Louis, Mauritius.  Herold was moving toward the southwest at 4 m.p.h. (6 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 996 mb.

A distinct low level center of circulation organized quickly in an area of thunderstorms east of Madagascar on Friday and the system was designated as Tropical Cyclone Herold.  The circulation around Herold was still organizing and the distribution of thunderstorms was asymmetrical.  Many of the stronger thunderstorms developed in bands northwest of the center of circulation.  Bands in other parts of the circulation consisted primarily of showers and lower clouds.  Thunderstorms northwest of the center of Herold were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out 85 miles (135 km) from the center of circulation.

Tropical Cyclone Herold will move through an environment that will become increasingly favorable for intensification during the next several days.  Herold is currently under a small upper level ridge centered near Madagascar.  The ridge is producing southeasterly winds which are blowing toward the top of the circulation.  Those winds are causing some vertical wind shear and they are probably the reason for the asymmetrical distribution of thunderstorms.  However, Tropical Cyclone Herold will move into a region where the upper level winds are weaker during the weekend.  Herold will move over water where the Sea Surface Temperature is near 29°C during that time period.  Tropical Cyclone Herold will intensify during the next several days and it could intensify rapidly once the inner core becomes better organized.  Herold is likely to intensify into the equivalent of a hurricane/typhoon during the next 24 hours.  It could strengthen into the equivalent of a major hurricane during the next 72 hours.

Tropical Cyclone Herold is currently in an area where the steering currents are weak.  A subtropical high pressure system over the South Indian Ocean will strengthen during the next several days.  The western end of the subtropical high will start to steer Herold toward the east-southeast during the weekend.  On its anticipated track the center of Tropical Cyclone Herold could be northwest of Mauritius in less than 72 hours.  Herold is likely to be the equivalent of a major hurricane at that time.

Major Tropical Cyclone Joaninha Brings Wind and Rain to Rodrigues

Major Tropical Cyclone Joaninha brought wind and rain to Rodrigues on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Joaninha was located at latitude 19.3°S and longitude 63.9°E which put it about 45 miles (75 km) from Rodrigues, Mauritius.  Joaninha was moving toward the southeast at 10 m.p.h. (16 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 946 mb.

Tropical Cyclone Joaninha was the equivalent of a major hurricane.  Winds to hurricane/typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 180 miles (290 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Joaninha was 23.6.  The Hurricane Size Index (HSI) was 18.7 and the Hurricane Wind Intensity Size Index (HWISI) was 42.3.  Joaninha was capable of causing major damage.

The southwestern portion of the eyewall of Tropical Cyclone Joaninha was very near Rodrigues.  Winds to hurricane typhoon force were occurring in that part of the eyewall.  Winds to tropical storm force are likely to affect all of Rodrigues.  The circulation around Joaninha was somewhat asymmetrical.  Most of the stronger rainbands were occurring in the eastern half of the circulation and the heaviest rain is likely to fall east of Rodrigues.  However, heavy rain in the eyewall could cause flooding in some locations.

Tropical Cyclone Joaninha will move through an environment favorable for intensification during the next 24 hours.  Joaninha will move over water where the Sea Surface Temperature is near 28°C.  It will move through a region where there will be little vertical wind shear.  Tropical Cyclone Joaninha could strengthen slightly while it passes by Rodrigues.

An upper level trough near Madagascar will produce northwesterly winds which will steer Tropical Cyclone Joaninha toward the southeast.  On its anticipated track Joaninha will move away from Rodrigues on Tuesday.  Conditions in Rodrigues should improve gradually as Tropical Cyclone Joaninha moves away.

Elsewhere over the South Indian Ocean, weakening Tropical Cyclone Veronica was skirting the coast of Western Australia.  At 11:00 p.m. EDT on Monday the center of Tropical Cyclone Veronica was located at latitude 21.1°S and longitude 115.4°E which put it about 140 miles (230 km) northeast of Learmonth, Australia.  Veronica was moving toward the southwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 992 mb.  Tropical Cyclone Veronica dropped heavy rain over parts of Western Australia and flooding was occurring in some locations.

Tropical Cyclone Joaninha Develops Over Southwest Indian Ocean

Tropical Cyclone Joaninha developed over the Southwest Indian Ocean on Friday.  At 5:00 p.m. EDT on Friday the center of Tropical Cyclone Joaninha was located at latitude 15.7°S and longitude 62.2°E which put it about 260 miles (420 km) north-northwest of Rodrigues, Mauritius.  Joaninha was moving toward the south 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 992 mb.

More thunderstorms developed near the center of a low pressure system over the Southwest Indian Ocean on Friday and the system was designated Tropical Cyclone Joaninha.  The inner end of a band of showers and thunderstorms wrapped around the eastern and southern sides of the center of circulation.  However, the distribution of thunderstorms around Joaninha was asymmetrical.  Several bands of thunderstorms developed in the eastern half of the circulation.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Thunderstorms near the center were generating upper level divergence which was pumping mass away from the tropical cyclone.  Winds to tropical storm force extended out about 150 miles (240 km) from the center of circulation.

Tropical Cyclone Joaninha will move through an environment favorable for intensification during the next several days.  Joaninha will move over water where the Sea Surface Temperature is near 29°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Cyclone Joaninha will continue to intensify during the next 48 to 72 hours.  Joaninha could strengthen into the equivalent of a hurricane/typhoon within 24 hours.  It could be the equivalent of a major hurricane in 48 to 72 hours.

Tropical Cyclone Joaninha will move around the western end of a ridge of high pressure.  The ridge will steer Joaninha toward the south for another day or so.  After it rounds the western end of the ridge, Tropical Cyclone Joaninha will move more toward the southeast.  On its anticipated track Joaninha could approach Rodrigues in about 72 hours.  It could be the equivalent of a major hurricane at that time.