Tag Archives: HWISI

Tropical Cyclone Vince Intensifies to Equivalent of a Major Hurricane

Tropical Cyclone Vince intensified to the equivalent of a major hurricane over the South Indian Ocean southwest of the Cocos Islands during Monday night.  At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Vince was located at latitude 18.6°S and longitude 89.6°E which put the center about 595 miles (960 km) southwest of the Cocos Islands.  Vince was moving toward the southwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h).  The minimum surface pressure was 958 mb.

Tropical Cyclone Vince intensified to the equivalent of a major hurricane during Monday night.  Vince appeared to go through an eyewall replacement cycle after it intensified.  The inner end of a rainband wrapped around the original small eye at the center of Vince’s circulation.  The small eye dissipated and a larger outer eye formed.

The circulation around Tropical Cyclone Vince weakened after the eyewalll replacement cycle.  A ring of thunderstorms surrounded the new larger eye.  The strongest winds were occurring in that ring of storms.  The distribution of thunderstorms around Tropical Cyclone Vince was asymmetrical.  Most of the thunderstorms were occurring in bands in the western side of Vince’s circulation.  Bands in the eastern side of Tropical Cyclone Vince consisted primarily of showers and lower clouds.  Storms near the center of Vince generated upper level divergence that pumped mass away to the west of the tropical cyclone.

The eyewall replacement cycle caused the size of the circulation around Tropical Cyclone Vince to increase.  Winds to hurricane/typhoon force extended out 50 miles (80 km) from the center of Vince’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center of Tropical Cyclone Vince.

The Hurricane Intensity Index (HII) for Tropical Cyclone Vince was 20.6.  The Hurricane Size Index (HSI) was 13.7 and the Hurricane Wind Intensity Size Index (HWISI) was 34.3.  Tropical Cyclone Vince was similar in size and intensity to Hurricane Delta when Delta hit Southwest Louisiana in 2020.

Tropical Cyclone Vince will move through an environment favorable for intensification during the next 24 hours.  Vince will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the northern part of an upper level ridge over the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Vince’s circulation.  Those winds will cause moderate vertical wind shear.  Even though Tropical Cyclone Vince will move through an environment favorable for intensification during the next 24 hours, Vince is likely to weaken due to the effects of the eyewall replacement cycle.

Tropical Cyclone Vince will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Vince toward the west-southwest during the next 24 hours.  On its anticipated track Tropical Cyclone Vince will pass far to the south of Diego Garcia later this week.

Elsewhere, Tropical Cyclone Taliah intensified as it moved farther away from Western Australia.  At 4:00 a.m. EST on Tuesday the center of Tropical Cyclone Taliah was located at latitude 15.6°S and longitude 110.4°E which put the center about 515 miles (830 km) north-northwest of Exmouth, Australia.  Taliah was moving toward the west at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 972 mb.

Tropical Cyclone Sean Rapidly Intensifies to Equivalent of Major Hurricane

Tropical Cyclone Sean rapidly intensified to the equivalent of a major hurricane over the South Indian Ocean west of Australia on Monday.  At 10:00 a.m. EST on Monday the center of Tropical Cyclone Sean was located at latitude 23.0°S and longitude 110.4°E which put the center about 210 miles (340 km) west of Exmouth, Australia.  Sean was moving toward the southwest at 13 m.p.h. (21 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 936 mb.

A Warning was in effect for the portion of the coast from Onslow to Ningaloo.  The Warning included Exmouth.

Tropical Cyclone Sean rapidly intensified to the equivalent of a major hurricane west of Australia on Monday.  A small circular eye with a diameter of 10 miles (16 km) was at the center of Sean’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Sean.  Storms near the core of Sean generated strong upper level divergence that pumped large quantities of mass away from the tropical cyclone.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Tropical Cyclone Sean was relatively small.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Sean’s circulation.  Winds to tropical storm force extended out 110 miles (175 km) from the center of Tropical Cyclone Sean.

The Hurricane Intensity Index (HII) for Tropical Cyclone Sean was 25.1.  The Hurricane Size Index (HSI) was 12.6 and the Hurricane Wind Intensity Size Index (HWISI) was 37.7.  Tropical Cyclone Sean was similar in size and intensity to Hurricane Harvey when Harvey hit Texas in 2017.

Tropical Cyclone Sean will move through an environment that will become unfavorable for intensification during the next 24 hours.  Sean will move over water where where the Sea Surface Temperatures are near 27°C.  It will move under the eastern part of an upper level trough over the South Indian Ocean.  The upper level trough will produce northwesterly winds are that will blow toward the top of Sean’s circulation.  Those winds will cause the vertical wind shear to increase.  The combination of cooler water and  more vertical wind shear will cause Tropical Cyclone Sean to weaken during the next 24 hours.

Tropical Cyclone Sean will move around the northwestern part of a high pressure system over Australia.  The high pressure system will steer Sean toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Sean will move a little farther away from the coast of Western Australia.

Bands in the eastern side of Tropical Cyclone Sea will bring gusty winds and locally heavy rain to the coast of Western Australia.  Heavy rain could cause floods in some locations.  10.78 inches (274 mm) of rain has already fallen at the Karratha Airport.  4.37 inches (111 mm) of rain has already fallen at the Mardie Airport.

Flood Warnings were in effect for parts of the Pilbara and northern Gascoyne regions.  A Flood Warning was in effect for the Lyndon-Minilya Rivers. 

 

Tropical Cyclone Dikeledi Passes Southwest of Madagascar

Tropical Cyclone Dikeledi passed southwest of Madagascar on Wednesday.  At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Dikeledi was located at latitude 26.4°S and longitude 42.9°E which put the center about 150 miles (240 km) southwest of Beloha, Madagascar.  Dikeledi was moving toward the south-southeast at 22 m.p.h. (35 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 963 mb.

Tropical Cyclone Dikeledi intensified on Wednesday as it moved southwest of Madagascar.  A circular eye with a diameter of 25 miles (40 km) formed at the center of Dikeledi’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Dikeledi.  Storms near the core of Dikeledi generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The size of the circulation around Tropical Cyclone Dikeledi increased on Wednesday.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Dikeledi’s circulation.  Winds to tropical storm force extended out 150 miles (240 km) in the eastern side of Tropical Cyclone Dikeledi.  Winds to tropical storm force only extended out 60 miles (95 km) in the western side of Dikeledi.

The Hurricane Intensity Index (HII) for Tropical Cyclone Dikeledi was 16.5.  The Hurricane Size Index (HSI) was 11.8 and the Hurricane Wind intensity Size INdex (HWISI) was 28.3.  Tropical Cyclone Dikeledi was similar in size and intensity to Hurricane Idalia when Idalia hit Florida in 2023.

Bands in the eastern side of Tropical Cyclone Dikeledi were bring gusty winds and heavy rain to southern Madagascar.  Heavy rain could cause flash floods in some locations.

Tropical Cyclone Dikeledi will move through an environment that will become unfavorable for intensification during the next 24 hours.  Dikeledi will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the eastern side of an upper level trough over southern Africa.  The upper level trough will produce northwesterly winds that will blow toward the top of Dikeledi’s circulation.  Those winds will cause the vertical wind shear to increase.  Tropical Cyclone Dikeledi will weaken when the wind shear increases.

The upper level trough over southern Africa will steer Tropical Cyclone Dikeledi toward the southeast during the next 24 hours.  On its anticipated track, Tropical Cyclone Dikeldi will pass south of Madagascar.  Dikeledi will move southeast of Madagascar on Thursday.

Tropical Cyclone Dikeledi Hits Northern Mozambique

Tropical Cyclone Dikeledi hit northern Mozambique on Monday morning.  At 7:00 a.m. EST on Monday the center of Tropical Cyclone Dikeledi was located at latitude 15.1°S and longitude 40.6°E which put the center about 30 miles (50 km) south of Nacala, Mozambique.  Dikeledi was moving toward the west-southwest at 18 m.p.h. (30 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 982 mb.

Tropical Cyclone Dikeledi hit the coast of northern Mozambique just to the south of Nacala on Monday morning.  Dikeledi was the equivalent of a hurricane/typhoon at the time the center made landfall.  A small circular eye was present at the center of Dikeledi’s circulation.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Tropical Cyclone Dikeledi.

The circulation around Tropical Cyclone Dikeledi was relatively small.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Dikeledi’s circulation. Winds to tropical storm force extended out 70 miles (110 km) from the center of Tropical Cyclone Dikeledi.

The Hurricane Intensity Index (HII) for Tropical Cyclone Dikeledi is 11.5.  The Hurricane Size Index (HSI) is 8.5 and the Hurricane Wind Intensity Size Index (HWISI) is 20.0.  Tropical Cyclone Dikeledi is similar in size to Hurricane Isaias when Isaias hit North Carolina in 2020.  Dikeledi is not as strong as Isaias was.

Tropical Cyclone Dikeledi will move around the western end of a high pressure system over the South Indian Ocean.  The high pressure system will steer Dikeledi toward the southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Dikeledi will move along the coast of northern Mozambique during the next 24hours.

The center of Tropical Cyclone Dikeledi will be just inland along the coast of northern Mozambique south of Nacala during the next 24 hours.  Dikeledi will bring strong winds and heavy rain to the coast of Mozambique.  Heavy rain is likely to cause flash floods in some locations.  Dikeledi could cause a storm surge of up to 7 feet (2 meters) along the coast of northern Mozambique.  Tropical Cyclone Dikeledi could move back over the Mozambique Channel later this week.

Tropical Cyclone Dikeledi Moves Over the Mozambique Channel

Tropical Cyclone Dikeledi moved over the northern Mozambique Channel on Sunday.  At 4:00 p.m. EST on Sunday the center of Tropical Cyclone Dikeledi was located at latitude 14.6°S and longitude 43.4°E which put the center about 215 miles (345 km) east of Nacala, Mozambique.  Dikeledi was moving toward the west-southwest at 11 m.p.h. (17 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 981 mb.

Tropical Cyclone Dikeledi weakened as it moved across northern Madagascar on Saturday night.  An eye was no longer at the center of Dikeledi’s circulation.  The inner end of a rainband was still wrapped around the northern side of center of Tropical Cyclone Dikeledi.  Other bands of showers and thunderstorms were revolving around the center of Dikeledi’s circulation.  Storms near the center generated upper level divergence that pumped mass away from the tropical cyclone.

The circulation around Tropical Cyclone Dikeledi was relatively symmetrical.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Dikeledi’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Dikeledi.

The Hurricane Intensity Index (HII) for Tropical Cyclone Dikeledi is 11.5.  The Hurricane Size Index (HSI) is 7.7 and the Hurricane Wind Intensity Size Index (HWISI) is 19.2  Tropical Cyclone Dikeledi is similar in size to Hurricane Isaias when Isaias hit North Carolina in 2020.  Dikeledi is not as strong as Isaias was.

Tropical Cyclone Dikeledi will move through an environment favorable for intensification during the next 24 hours.  Dikeledi will move over water where where the Sea Surface Temperatures are near 30°C.  It will move under the northern part of an upper level ridge over southern Africa and the Mozambique Channel.  The upper level ridge will produce easterly winds that will blow toward the top of Dikeledi’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Cyclone Dikeledi is likely to intensify during the next 24 hours.

Tropical Cyclone Dikeledi will move around the northwestern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Dikeledi toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Dikeledi will approach northern Mozambique in 18 hours.  The steering winds will weaken on Monday and Dikeledi will move more slowly when it approaches northern Mozambique.

The center of Tropical Cyclone Dikeledi will be near the coast of northern Mozambique south of Nacala in 24 hours.  Dikeledi will bring strong winds and heavy rain to the coast of Mozambique.  Heavy rain is likely to cause flash floods in some locations.  Dikeledi could cause a storm surge of up to 7 feet (2 meters) along the coast of northern Mozambique.

Tropical Cyclone Dikeledi Brings Wind and Rain to Northern Madagascar

Tropical Cyclone Dikeledi brought wind and rain to northern Madagascar on Saturday.  At 4:00 p.m. EST on Saturday the center of Tropical Cyclone Dikeledi was located at latitude 13.1°S and longitude 48.4°E which put the center about 60 miles (95 km) south of Antsiranana, Madagascar.  Dikeledi was moving toward the west-southwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 980 mb.

Tropical Cyclone Dikeledi intensified to the equivalent of a hurricane/typhoon before it reached northern Madagascar on Saturday.  The inner end of a rainband wrapped around the center of Dikeledi’s circulation.  An eye appeared intermittently on microwave satellite images.  The intermittent eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core to Tropical Cyclone Dikeledi.  Storms near the core generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass caused the surface pressure to decrease.

The circulation around Tropical Cyclone Dikeledi was symmetrical.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Dikeledi’s circulation.  Winds to tropical storm force extended out 100 miles (160 km) from the center of Tropical Cyclone Dikeledi.

The Hurricane Intensity Index (HII) for Tropical Cyclone Dikeledi is 12.7.  The Hurricane Size Index (HSI) is 9.5 and the Hurricane Wind Intensity Size Index (HWISI) is 22.2  Tropical Cyclone Dikeledi is similar in size and intensity to Hurricane Isaias when Isaias hit North Carolina in 2020.

Tropical Cyclone Dikeledi will move across northern Madagascar during the next few hours.  Dikeledi is capable of causing localized minor wind damage.  Tropical Cyclone Dikeledi will also drop heavy rain over parts of northern Madagascar.  Heavy rain is likely to cause flash floods in some locations.

Tropical Cyclone Dikeledi will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Dikeledi toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Dikeledi will move across northern Madagascar during the next few hours.  The center of Dikeledi’s circulation will pass near Mayotte on Sunday.

Tropical Cyclone Dikeledi will weaken while it moves across northern Madagascar.  Dikeledi will will move through an environment favorable for intensification when it reaches the northern Mozambique Channel on Sunday.  Dikeledi will move over water where where the Sea Surface Temperatures are near 30°C. It will move under the northern part of an upper level ridge over the South Indian Ocean.  The upper level ridge will produce easterly winds that will blow toward the top of Dikeledi’s circulation.  Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Cyclone Dikeledi is likely to intensify on Sunday when it gets to the northern Mozambique Channel.

Tropical Cyclone Chido Hits Northern Mozambique

Powerful Tropical Cyclone Chido hit the coast of northern Mozambique on Saturday night.  At 11:00 p.m. EST on Saturday the center of Tropical Cyclone Chido was located at latitude 13.5°S and longitude 40.6°E which put the center about 75 miles (120 km) north of Nacala, Mozambique.  Chido was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 950 mb.

Powerful Tropical Cyclone Chido hit the coast of northern Mozambique less than 24 hours after Chido caused major damage in Mayotte.  The center of Tropical Cyclone Chido made landfall on the coast north of Nacala.  Chido was the equivalent of a Category 4 hurricane on the Saffir-Simpson Scale at the time of landfall.  A small circular eye with a diameter of 12 miles (19 km) was at the center of Chido’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Chido.

The circulation around Tropical Cyclone Chido was small.  Winds to hurricane/typhoon force extended out 25 miles (40 km) from the center of Chido’s circulation.  Winds to tropical storm force extended out 80 miles (130 km) from the center of Tropical Cyclone Chido.

The Hurricane Intensity Index (HII) for Tropical Cyclone Chido is 25.1.  The Hurricane Size Index (HSI) is 8.0 and the Hurricane Wind Intensity Size Index (HWISI) is 33.1.  Tropical Cyclone Chido is similar in intensity to Hurricane Harvey when Harvey made landfall in Texas in 2017.  Chido is not as large as Harvey was.

Tropical Cyclone Chido will bring strong winds and heavy rain to northern Mozambique.  Heavy rain is likely to cause floods in some locations.  Chido could also cause a storm surge of up to 10 feet (3 meters) along the coast of northern Mozambique.

Tropical Cyclone Chido will move around the northern side of a high pressure system over the Southwest Indian Ocean.  The high pressure system will steer Chido toward the west-southwest during the next 24 hours.  On its anticipated track, Tropical Cyclone Chido will move inland over northern Mozambique.

Tropical Cyclone Chido will weaken steadily as it moves inland over northern Mozambique.  However, Chido will still bring strong winds and locally heavy rain to northern Mozambique.  Tropical Cyclone Chido could also drop heavy rain on parts of southern Malawi.

Tropical Cyclone Chido Batters Mayotte

Tropical Cyclone Chido battered Mayotte during Friday night.  A weather station at the Dzaoudzi-Pamandzi International Airport (FMCZ) in Mayotte reported a sustained wind speed of 84 knots (97 m.p.h. or 156 km/h) during the passage of Tropical Cyclone Chido.  The weather station also reported a wind gust of 99 knots (114 m.p.h. or 184 km/h) during the passage of Chido.  Tropical Cyclone Chido most likely caused major damage on Mayotte.

At 4:00 a.m. EST on Saturday the center of Tropical Cyclone Chido was located at latitude 12.7°S and longitude 44.8°E which put the center about 20 miles (30 km) west of Mayotte.  Chido was moving toward the west-southwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 952 mb.

Tropical Cyclone Chido strengthened as it approached Mayotte on Friday night.  A circular eye with a diameter of 15 miles (24 km) was at the center of Chido’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Chido.  Storms near the core of Chido generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass in the upper levels exceeded the stronger inflow of mass in the lower levels of the atmosphere.  The greater upper level divergence caused the surface pressure to decrease.

The circulation around Tropical Cyclone Chodi was very symmetrical.  Winds to hurricane/typhoon force extended out 35 miles (55 km) from the center of Chido’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Chido.

The Hurricane Intensity Index (HII) for Tropical Cyclone Chido is 25.1.  The Hurricane Size Index (HSI) is 12.5 and the Hurricane Wind Intensity Size Index (HWISI) is 37.6.  Tropical Cyclone Chido is similar in size and intensity to Hurricane Harvey when Harvey made landfall in Texas in 2017.

The southern part of the eyewall of Tropical Cyclone Chido passed directly over Mayotte.  Chido likely caused major damage in Mayotte.  Tropical Cyclone Chido also dropped heavy rain on Mayotte and flash floods are likely.

Tropical Cyclone Chido will move through an environment favorable for a powerful tropical cyclone during the next 18 hours.  Chido will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the axis of an upper level ridge over the South Indian Ocean.  The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.  Tropical Cyclone Chido could maintain its intensity during the next 18 hours if the inflow of mass in the lower levels is balanced by the divergence of mass in the upper levels of the atmosphere.  Chido could weaken if the inflow of mass in the lower levels exceeds the divergence of mass in the upper levels.

Tropical Cyclone Chido will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Chido toward the west-southwest during the next 24 hours.  On its anticipated track, the center of Tropical Cyclone Chido will reach the coast of northern Mozambique in 18 hours.

Tropical Cyclone Chido is likely to make landfall on the coast of northern Mozambique near Pemba.  Chido could be the equivalent of a major hurricane when it hits northern Mozambique.  Tropical Cyclone Chido will bring strong winds and locally heavy rain to northern Mozambique. Heavy rain is likely to cause flash floods in some locations.  Chido will be capable of causing regional major damage.

Tropical Cyclone Chido Approaches Mayotte

Tropical Cyclone Chido was approaching Mayotte and Comoros on Friday afternoon.  At 4:00 p.m. EST on Friday the center of Tropical Cyclone Chido was located at latitude 12.1°S and longitude 47.0°E which put the center about 135 miles (215 km) east-northeast of Mayotte.  Chido was moving toward the west-southwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 969 mb.

Tropical Cyclone Chido was weakening slowly as it approached Mayotte on Friday afternoon.  A circular eye with a diameter of 15 miles (24 km) was at the center of Chido’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Chido.  Storms near the core of Chido generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass in the upper levels was not quite able to balance the stronger inflow of mass in the lower levels of the atmosphere.  The greater inflow of mass in the lower levels caused the surface pressure to increase.

The circulation around Tropical Cyclone Chodi was very symmetrical.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Chido’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Chido.

The Hurricane Intensity Index (HII) for Tropical Cyclone Chido is 17.8.  The Hurricane Size Index (HSI) is 15.7 and the Hurricane Wind Intensity Size Index (HWISI) is 33.5.  Tropical Cyclone Chido is similar in size and intensity to Hurricane Sally when Sally made landfall in south Alabama in 2020.

Tropical Cyclone Chido will move through an environment favorable for a powerful tropical cyclone during the next 24 hours.  Chido will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the axis of an upper level ridge over the South Indian Ocean.  The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.  Tropical Cyclone Chido could maintain its intensity during the next 24 hours if the inflow of mass in the lower levels is balanced by the divergence of mass in the upper levels of the atmosphere.

Tropical Cyclone Chido will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Chido toward the west-southwest during the next 24 hours.  On its anticipated track, the center of Tropical Cyclone Chido will reach Mayotte in 12 hours.  Chido could approach the coast of northern Mozambique in 36 hours.

Tropical Cyclone Chido could be the equivalent of a major hurricane when it reaches Mayotte and the Comoros.  The center of Chido will pass very close to Mayotte.  Tropical Storm Chido will bring strong winds and locally heavy rain to Mayotte.  Chido could also bring strong winds and heavy rain to the southern Comoros.  Heavy rain is likely to cause flash floods in some locations.  Tropical Cyclone Chido could also cause a storm surge of up to 10 feet (3 meters) along the coast of Mayotte and the southern Comoros.

Tropical Cyclone Chido Passes North of Madagascar

The center of Tropical Cyclone Chido passed just to the north of Madagascar on Friday morning.  At 4:00 a.m. EST on Friday the center of Tropical Cyclone Chido was located at latitude 12.0°S and longitude 49.4°E which put the center about 75 miles (120 km) north of Antsiranana, Madascar.  Chido was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 960 mb.

Tropical Cyclone Chido was weakening slowly as it passed just to the north of Madagascar on Friday morning.  A circular eye with a diameter of 25 miles (40 km) was at the center of Chido’s circulation.  The eye was surrounded by a 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 Tropical Cyclone Chido.  Storms near the core of Chido generated upper level divergence that pumped mass away from the tropical cyclone.  The removal of mass in the upper levels was not quite able to balance the stronger inflow of mass in the lower levels of the atmosphere.  The greater inflow of mass in the lower levels caused the surface pressure to increase.

The circulation around Tropical Cyclone Chodi was very symmetrical.  Winds to hurricane/typhoon force extended out 45 miles (75 km) from the center of Chido’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) from the center of Tropical Cyclone Chido.

The Hurricane Intensity Index (HII) for Tropical Cyclone Chido is 22.1.  The Hurricane Size Index (HSI) is 15.0 and the Hurricane Wind Intensity Size Index (HWISI) is 37.1.  Tropical Cyclone Chido is similar in size and intensity to Hurricane Delta when Delta made landfall in southwest Louisiana in 2020.

Tropical Cyclone Chido will move through an environment favorable for a powerful tropical cyclone during the next 24 hours.  Chido will move over water where where the Sea Surface Temperatures are near 28°C.  It will move under the axis of an upper level ridge over the South Indian Ocean.  The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear.  Tropical Cyclone Chido could maintain its intensity during the next 24 hours if the inflow of mass in the lower levels is balanced by the divergence of mass in the upper levels of the atmosphere.

Tropical Cyclone Chido will move around the northern side of a high pressure system over the South Indian Ocean.  The high pressure system will steer Chido toward the west-southwest during the next 24 hours.  On its anticipated track, the center of Tropical Cyclone Chido will reach Mayotte and the Comoros in 24 hours.  Chido could approach the coast of northern Mozambique in 48 hours.

Tropical Cyclone Chido could be the equivalent of a major hurricane when it reaches Mayotte and the Comoros.  Chido will bring strong winds and locally heavy rain to Mayotte and the Comoros.  Heavy rain is likely to cause flash floods in some locations.  Tropical Cyclone Chido could also cause a storm surge of up to 10 feet (3 meters) along the coast of Mayotte and the Comoros.