Monthly Archives: November 2020

Tropical Cyclone Nivar Makes Landfall in Tamil Nadu

Tropical Cyclone Nivar made landfall on the coast of Tamil Nadu on Wednesday. At 4:00 p.m. EST on Wednesday the center of Tropical Cyclone Nivar was located at latitude 12.2°N and longitude 79.8°E which put it about 25 miles (40 km) north of Puducherry, India. Nivar was moving toward the west-northwest at 12 m.p.h. (19 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 976 mb.

Tropical Cyclone Nivar made landfall on the southeast coast of India north of Puducherry on Wednesday. Nivar strengthened into the equivalent of a hurricane/typhoon over the Bay of Bengal before it made landfall. Winds to hurricane/typhoon force extended out 35 miles (55 km/h) from the center of Tropical Cyclone Nivar. Winds to tropical storm force extended out 150 miles (240 km) from the center of circulation.

Tropical Cyclone Nivar will produce gusty winds along the coast of Tamil Nadu between Cuddalore and Chennai. Winds blowing water toward the coast could cause a storm surge of up to six feet (two meters) between Puducherry and Chennai. Nivar will drop heavy rain over parts of northern Tamil Nadu and flash floods could occur in some locations.

Tropical Cyclone Nivar will move south of a high pressure system over India and the Bay of Bengal. The high will steer Nivar toward the west-northwest. The wind speed will steadily decrease when Tropical Cyclone Nivar moves inland. Nivar will drop locally heavy rain over parts of southern Andhra Pradesh and Karnataka when it moves farther inland over southern India.

Tropical Cyclone Nivar Strengthens near Southeast India

Tropical Cyclone Nivar (04B) strengthened over the Bay of Bengal near Southeast India on Tuesday. At 10:00 p.m. EST on Tuesday the center of Tropical Cyclone Nivar was located at latitude 10.8°N and longitude 82.6°E which put it about 235 miles (380 km) southeast of Chennai India. Nivar was moving toward the northwest at 5 m.p.h. (8 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 Nivar strengthened to almost the equivalent of a hurricane/typhoon over the Bay of Bengal near Tamil Nadu on Tuesday. More thunderstorms developed near the center of Nivar. Other strong thunderstorms were occurring in bands north and west of the center of circulation. Bands south and east of the center consisted primarily of showers and lower clouds. Storms near the center generated upper level divergence which pumped mass away to the north and west of the tropical cyclone. Winds to tropical storm force extended out 110 miles (175 km) from the center of circulation.

Tropical Cyclone Nivar will move through an environment favorable for intensification during the next 24 hours. Nivar will move over water where the Sea Surface Temperature is near 29°C. It will move under the western end of an upper level ridge over the Bay of Bengal. The ridge will enhance the upper level divergence and contribute to the removal of mass, which will cause the surface pressure to decrease. Tropical Cyclone Nivar will intensify into the equivalent of a hurricane/typhoon during the next 24 hours.

Tropical Cyclone Nivar will move around the western part of a high pressure system over Bay of Bengal. The high will steer Nivar toward the northwest during the next 24 hours. On its anticipated track Tropical Cyclone Nivar will make landfall on the coast of India between Puducherry and Chennai in about 24 hours. Nivar will bring strong winds to southern India. Wind blowing water toward the coast will cause a storm surge of up to 6 feet (2 meters). Tropical Cyclone Nivar will drop heavy rain over parts of Tamil Nadu and flash floods could occur.

Tropical Cyclone 04B Forms over Bay of Bengal

Tropical Cyclone 04B formed over the Bay of Bengal east of Sri Lanka. At 4:00 p.m. EST on Monday the center of Tropical Cyclone Gati (03A) was located at latitude 9.9°N and longitude 83.0°E which put it about 210 miles (340 km) east-southeast of Puducherry India and about 200 miles (320 km) east of Jaffna, Sri Lanka. It was moving toward the west 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 997 mb.

The circulation around a low pressure system east of Sri Lanka strengthened on Monday. More thunderstorms developed near the center of the low and the wind speeds increased. The distribution of thunderstorms around the low was asymmetrical. Most of the thunderstorms were occurring in bands in the western half of the circulation. Bands in the eastern half of the tropical cyclone consisted primarily of showers and lower clouds. Storms near the center of circulation generated upper level divergence which pumped mass away to the west of the tropical cyclone.

Tropical Cyclone 04B will move through an environment that is mostly favorable for intensification during the next during the next 36 hours. It will move over water where the Sea Surface Temperature is near 29°C. The tropical cyclone will move under the southern side of an upper level ridge over the Bay of Bengal. The ridge will produce easterly winds which will blow toward the top of the circulation. Those winds will cause moderate vertical wind shear and they are probably the reason for the asymmetrical distribution of thunderstorms. The wind shear will slow the rate of intensification, but the shear will not be large enough to keep the tropical cyclone from strengthening. Tropical Cyclone 04B could intensify into the equivalent of a hurricane/typhoon with 36 hours.

Tropical Cyclone 04B will move south of a ridge of high pressure over the Bay of Bengal. The high will steer the tropical cyclone toward the west-northwest. On its anticipated track the center of Tropical Cyclone 04B will pass north of Sri Lanka in about 24 hours. The tropical cyclone will approach the coast of India near Puducherry in 36 hours. It could be the equivalent of a hurricane/typhoon when it reaches the southeast coast of India.

Tropical Cyclone 04B will drop locally heavy rain over northern Sri Lanka. It will bring strong winds and locally heavy rain to southern India later this week. Heavy rain could cause flash floods in some locations.

Elsewhere, Tropical Cyclone Gati weakened as it moved across northeastern Somalia toward the Gulf of Aden. At 4:00 p.m. EST on Monday the center of Tropical Cyclone Gati (03A) was located at latitude 11.9°N and longitude 47.5°E which put it about 45 miles (75 km) northwest of Maydh, Somalia. Gati was moving toward the west-northwest at 13 m.p.h. (20 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 1003 mb.

Tropical Cyclone Gati Intensifies Explosively near Somalia

Tropical Cyclone Gati intensified explosively near the northeast coast of Somalia during Saturday night. At 4:00 a.m. EST on Sunday the center of Tropical Cyclone Gati (03A) was located at latitude 10.3°N and longitude 52.0°E which put it about 70 miles (110 km) east of Hafun, Somalia. It was moving toward the west at 16 m.p.h. (26 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 954 mb.

Tropical Cyclone Gati strengthened extremely rapidly on Saturday night. A circular eye with a diameter of 17 miles (28 km) developed at the center of Gati. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Storms around the core of Gati generated very strong upper level divergence which pumped mass away from the tropical cyclone. The removal of large amounts of mass allowed the surface pressure to decrease very rapidly, which contributed to the explosive intensification.

The circulation around Tropical Cyclone Gati was very small. Winds to hurricane/typhoon force extended out 20 miles (30 km) from the center of Gati. Winds to tropical storm force extended out 60 miles (95 km) from the center. The Hurricane Intensity Index (HII) for Tropical Cyclone Gati was 20.6. The Hurricane Size Index (HSI) was 5.5 and the Hurricane Wind Intensity Size Index (HWISI) was 26.1. The structure of Gati was similar to that of midget typhoons sometimes observed over the Western North Pacific Ocean.

Tropical Cyclone Gati could strengthen further during the next few hours before it makes landfall on the northeast coast of Somalia. Gati will move over water where the Sea Surface Temperature is near 27°C. It will move through an area where the upper level winds are weak and there will be little vertical wind shear. Tropical Cyclone Gati will weaken quickly after it makes landfall in Somalia.

Tropical Cyclone Gati will move south of a high pressure system over th Arabian Peninsula. The high will steer Gati toward the west during the next 36 to 48 hours. On its anticipated track Tropical Cyclone Gati wil make landfall near Hafun, Somalia in about six hours. Gati will be capable of causing major damage around Hafun. It will drop heavy rain over parts of northeastern Somalia and flash floods could occur.

Tropical Cyclone 03A Forms East of Somalia

Tropical Cyclone 03A formed over the Arabian Sea east of Somalia on Saturday. At 4:00 p.m. EST on Saturday the center of Tropical Cyclone 03A was located at latitude 10.8°N and longitude 55.0°E which put it about 270 miles (435 km) east of Hafun, Somalia. It was moving toward the west at 17 m.p.h. (26 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 1000 mb.

More thunderstorms developed near the center of a low pressure system east of Somalia on Saturday and it strengthened into Tropical Cyclone 03A. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence which pumped mass away from the tropical cyclone. Winds to tropical storm force extended out 75 miles (120 km) from the center of the tropical cyclone.

Tropical Cyclone 03A will move through an environment somewhat favorable for intensification during the next 24 hours. It will move over water where the Sea Surface Temperature is near 27°C. The tropical cyclone will move under the southern portion of an upper level ridge over southern Asia. The ridge will produce easterly winds which will blow toward the top of the tropical cyclone. Those winds will cause moderate vertical wind shear. The shear will inhibit intensification, but Tropical Cyclone 03A is likely to strengthen during the next 24 hours in spite of the wind shear.

Tropical Cyclone 03A will move south of a high pressure system over the Arabian Peninsula. The high will steer the tropical cyclone toward the west during the next 24 hours. On its anticipated track Tropical Cyclone 03A will pass south of Socotra Island during the next 12 hours. It will approach the coast of Somalia near Hafun in about 24 hours. The tropical cyclone will bring gusty winds and locally heavy rain to northeastern Somalia in about a day or so.

Tropical Storm Polo Forms Southwest of Baja California

Tropical Storm Polo formed southwest of Baja California formed southwest of Baja California on Wednesday morning. At 10:00 a.m. EST on Wednesday the center of Hurricane Iota was located at latitude 13.8°N and longitude 116.0°W which put it about 605 miles (970 km) southwest of the southern tip of Baja California. Polo was moving toward the west-northwest at 12 m.p.h. (19 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 1004 mb.

More thunderstorms developed near the center of a low pressure system southwest of Baja California on Wednesday morning and the National Hurricane Center designated the system as Tropical Storm Polo. The circulation around Tropical Storm Polo was small. Winds to tropical storm force extended out 35 miles (55 km) from the center of circulation. The strongest thunderstorms were occurring in a band that wrapped around the eastern and southern sides of the center of Polo. Storms near the center generated upper level divergence which pumped mass away from the tropical storm.

Tropical Storm Polo will move through an environment favorable for intensification during the next 24 hours. Polo will move over water where the Sea Surface Temperature is near 27.5°C. It will move through a region where the upper level winds are weak during the next 24 hours and there will be little vertical wind shear. Tropical Storm Polo could intensify more on Wednesday. Polo will move closer to an upper level trough over the Eastern North Pacific Ocean on Thursday. The trough will produce southwesterly winds which will blow toward the top of Tropical Storm Polo. Those winds will cause moderate vertical wind shear and the shear will cause Polo to start to weaken later this week.

Tropical Storm Polo will move south of an high pressure system over the Eastern North Pacific Ocean. The high will steer Polo toward the west during the next several days. On its anticipated track Tropical Storm Polo will move farther away from Mexico.

Elsewhere, Tropical Depression Iota was moving across El Salvador. At 10:00 a.m. EST on Wednesday the center of Tropical Depression Iota was located at latitude 13.8°N and longitude 89.5°W which put it about 20 miles (30 km) west-northwest of San Salvador, El Salvador. Iota was moving toward the west at 12 m.p.h. (19 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 1006 mb.

Hurricane Iota Drops Heavy Rain over Nicaragua and Honduras

Hurricane Iota was dropping heavy rain over Nicaragua and Honduras on Tuesday morning. At 10:00 a.m. EST on Tuesday the center of Hurricane Iota was located at latitude 13.7°N and longitude 85.2°W which put it about 135 miles (220 km) east of Tegucigapla, Honduras. Iota was moving toward the west at 12 m.p.h. (19 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 980 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Bluefields, Nicaragua to the Honduras/Guatemala border including the Bay Islands.

Hurricane Iota continued to move steadily inland over Nicaragua on Tuesday morning. The center of Iota was just to the east of the border between Nicaragua and Honduras. Hurricane Iota was dropping heavy rain over much of Nicaragua and Honduras. Bands of showers and thunderstorms continued to revolve around the center of Iota. Those rainbands were dropping rain fast enough to cause flash floods over many of the same places that were flooded by Hurricane Eta.

Hurricane Iota will continue to move westward during the next 24 to 36 hours. Iota will weaken to a tropical storm when its center moves over Honduras during the next few hours. Iota will likely be a tropical depression when the center reaches El Salvador on Tuesday night. Even though Hurricane Iota will weaken steadily, it will continue to drop heavy rain over Nicaragua, Honduras and El Salvador. Catastrophic flash floods could occur in that region.

Dangerous Hurricane Iota Hits Nicaragua

Dangerous Hurricane Iota hit Nicaragua with powerful winds and heavy rain on Monday night. At 10:00 p.m. EST on Monday the center of Hurricane Iota was located at latitude 13.6°N and longitude 83.4°W which put it about 30 miles (50 km) south of Puerto Cabezas, Nicaragua. Iota was moving toward the west at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 185 m.p.h. (300 km/h). The minimum surface pressure was 920 mb.

A Hurricane Warning was in effect for the portion of the coast from Sandy Bay Sirpi, Nicaragua to Punta Patuca, Honduras. Tropical Storm Warnings were in effect for the portions of the coast from Bluefields to Sandy Bay Sirpi, Nicaragua and from Punta Patuca to the Honduras/Guatemala border including the Bay Islands. Tropical Storm Warnings were also in effect for San Andres and Providencia Island.

Hurricane Iota was a powerful hurricane when it made landfall on the coast of Nicaragua just to the south of Puerto Cabezas. Iota was at Category 4 on the Saffir-Simpson Scale. Winds to hurricane force extended out 45 miles (75 km) from the center of circulation. Winds to tropical storm force extended out 175 miles (280 km) from the center, The Hurricane Intensity Index (HII) for Hurricane Iota was 33.3. The Hurricane Size Index (HSI) was 16.3 and the Hurricane Wind Intensity Size Index (HWISI) was 49.6. Iota was capable of causing regional significant damage.

Hurricane Iota made landfall on the same portion of the coast of Nicaragua devastated by Hurricane Eta two weeks ago. Iota will compound the damage caused by Eta. Strong winds will cause additional damage and they will destroy temporary shelters erected after Hurricane Eta. The winds blowing water toward the coast could cause a storm surge of up to 20 feet (6 meters) south of Puerto Cabezas.

Hurricane Iota will continue to move toward the west during the next 48 hours. On its anticipated track the center of Iota will move across northern Nicaragua, southern Honduras and El Salvador. The winds around Hurricane Iota will weaken steadily as it moves inland. Iota will drop heavy rain over Nicaragua, Honduras, and El Salvador. The heavy rain will cause flash floods and some floods will occur in the same locations flooded by Hurricane Eta.

Hurricane Iota Rapidly Intensifies to Cat. 5

Hurricane Iota rapidly intensified to Category 5 on the Saffir-Simpson Scale on Monday morning. At 10:00 a.m. EST on Monday the center of Hurricane Iota was located at latitude 13.5°N and longitude 82.0°W which put it about 100 miles (160 km) east-southeast of Cabo Gracias a Dios. Iota was moving toward the west at 9 m.p.h. (15 km/h). The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 190 m.p.h. (305 km/h). The minimum surface pressure was 917 mb.

A Hurricane Warning was in effect for the portion of the coast from Sandy Bay Sirpi, Nicaragua to Punta Patuca, Honduras and for Providencia Island. A Hurricane Watch was in effect for San Andres. Tropical Storm Warnings were in effect for the portions of the coast from Bluefields to Sandy Bay Sirpi, Nicaragua and from Punta Patuca to the Honduras/Guatemala border including the Bay Islands. A Tropical Storm Warning was also in effect for San Andres.

Hurricane Iota intensified very rapidly on Sunday night and it reached Category 5 on the Saffir-Simpson Scale on Monday morning. A reconnaissance aircraft found a circular eye with a diameter of 14 miles (22 km) at the center of Iota. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Iota. Storms near the core generated strong upper level divergence which pumped mass away from the hurricane in all directions. The removal of large quantities of mass allowed the surface pressure to decrease rapidly which produced the very rapid intensification.

Winds to hurricane force extended out 35 miles (55 km) from the center of Hurricane Iota. Winds to tropical storm force extended out 150 miles (240 km) from the center. The Hurricane Intensity Index (HII) for Hurricane Iota was 35.0. The Hurricane Size Index (HSI) was 13.9 and the Hurricane Wind Intensity Size Index (HWISI) was 48.9. Hurricane Iota was capable of causing catastrophic damage.

Hurricane Iota will move through an capable of supporting a very intense hurricane on Monday. Iota 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. If the inner end of a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could begin. An eyewall replacement cycle could cause Hurricane Iota to start to weaken, but Iota could still be at Category 5 when it makes landfall on the northern coast of Nicaragua.

Hurricane Iota will move south of a high pressure system over the western Atlantic Ocean. The high will steer Iota toward the west during the next several days. On its anticipated track Iota could approach the coast a little to the south of the border between Nicaragua and Honduras on Monday night. Hurricane Iota will be a major hurricane when it reaches the coast and it could be at Category 5. Nicaragua and Honduras are still trying to cope with floods and other damage caused by Hurricane Eta. Another major hurricane could have catastrophic consequences for that region.

Hurricane Iota Rapidly Intensifies East of Nicaragua

Hurricane Iota rapidly intensified east of Nicaragua on Sunday morning. At 10:00 a.m. EST on Sunday the center of Hurricane Iota was located at latitude 13.2°N and longitude 77.8°W which put it about 380 miles (615 km) east-southeast of Cabo Gracias a Dios. Iota was moving toward the west-northwest at 6 m.p.h. (10 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 982 mb.

A Hurricane Warning was in effect for the portion of the coast from Sandy Bay Sirpi, Nicaragua to Punta Patuca, Honduras and for Providencia Island. A Hurricane Watch was in effect for San Andres. Tropical Storm Warnings were in effect for the portions of the coast from Bluefields to Sandy Bay Sirpi, Nicaragua and from Punta Patuca to Punta Castilla, Honduras. A Tropical Storm Warning was also in effect for San Andres.

Hurricane Iota was intensifying rapidly on Sunday morning. A small eye formed at the center of Iota. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Iota. Storms near the core generated strong upper level divergence which pumped mass away from the hurricane. The removal of mass caused the surface pressure to decrease quickly, which contributed to the rapid intensification. Winds to hurricane force extended out 30 miles from the center of circulation. Winds to tropical storm force extended out 90 miles from the center.

Hurricane Iota will move through an environment very favorable for intensification during the next 36 hours. Iota 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. Hurricane Iota is likely to continue to intensify rapidly. Iota could strengthen into a major hurricane within 24 hours and it could intensify to Category 4 on the Saffir-Simpson Scale.

Hurricane Iota will move south of a high pressure system over the western Atlantic Ocean. The high will steer Iota toward the west during the next several days. On its anticipated track Iota could approach the coast near the border between Nicaragua and Honduras on Monday night. Hurricane Iota is likely be a major hurricane when it reaches the coast. Nicaragua and Honduras are still trying to cope with floods and other damage caused by Hurricane Eta a few days ago. Another major hurricane could have catastrophic consequences for that region.

Elsewhere over the Atlantic Ocean, former Tropical Storm Theta weakened to a tropical depression southwest of Madeira. At 7:00 a.m. EST on Sunday the center of Tropical Depression Theta was located at latitude 31.8°N and longitude 18.3°W which put it about 120 miles (195 km) southwest of Madeira. Theta was moving toward the east at 3 m.p.h. (5 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 1003 mb.