Tag Archives: HWISI

Hurricane Laura Intensifies to Cat. 4

Hurricane Laura rapidly intensified to Category 4 on the Saffir-Simpson Scale on Wednesday.  At 2:00 p.m. EDT on Wednesday the center of Hurricane Laura was located at latitude 27.3°N and longitude 92.5°W which put it about 200 miles (320 km) south-southeast of Lake Charles, Louisiana.  Laura was moving toward the northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 170 m.p.h. (275 km/h).  The minimum surface pressure was 952 mb.

A Hurricane Warning was in effect for the portion of the coast from San Luis, Pass, Texas to Intracoastal City, Lousiana.  Tropical Storm Warnings were in effect for the portions of the coast from Sargent, Texas to San Luis Pass and from Intracoastal City to the Mouth of the Mississippi River.

Hurricane Laura continued to intensify rapidly on Wednesday morning.  The eye became more circular and well defined.  The ring of thunderstorms around the eye strengthened and the highest wind speeds were occurring in that ring of storms.   Storms near the core of Laura generated strong upper level divergence which pumped large quantities of mass away from the hurricane.  The continued removal of mass allowed a further rapid decrease in surface pressure.

Hurricane Laura grew into a large hurricane on Wednesday.  Winds to hurricane force extended out 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Laura.  The Hurricane Intensity Index (HII) for Hurricane Laura was 28.3.  The Hurricane Size Index (HSI) was 19.1 and the Hurricane Wind Intensity Size Index (HWISI) was 47.4.  Hurricane Laura was capable of causing widespread significant damage.

Hurricane Laura could strengthen during the next few hours.  Laura will move over water where the Sea Surface Temperature is near 30°C.  There is a possibility that Hurricane Laura could intensify to Category 5 on the Saffir-Simpson Scale.  When Hurricane Laura nears the coast of western Louisiana, it will be closer to an upper level trough over Texas and Oklahoma.  The trough will produce southwesterly winds which will blow toward the top of Laura.  Those winds will cause the vertical wind shear to increase and that could stop the intensification of Hurricane Laura.

Hurricane Laura will move around the western end of a subtropical high pressure system that extends from the Atlantic Ocean over the Gulf of Mexico.  Laura will start to move towards the north when it reaches the western end of the high.  On its anticipated track Hurricane Laura will make landfall south of Lake Charles, Louisiana in 8 to 10 hours.  After it makes landfall, Laura will move north over western Louisiana.

Hurricane Laura is a strong, extremely dangerous hurricane.  It is capable of causing widespread significant damage.  Laura will be stronger than Hurricane Rita was when Rita hit the same area in 2005.  Hurricane Laura will cause a storm surge of 15 to 20 feet (5 to 7 meters) near and to the east of where the center makes landfall.  Large sections of the southwest coast of Louisiana south of Interstate 10 will go underwater.  Hurricane Laura will bring hurricane force winds to much of western Louisiana and to extreme east Texas.  Widespread power outages are likely.  Hurricane Laura will drop heavy rain over parts of western Louisiana, eastern Texas and Arkansas.  Flash floods could result from the heavy rain

Hurricane Laura Rapidly Intensifies into a Major Hurricane

Hurricane Laura rapidly intensified into a major hurricane during the overnight hours.  At 8:00 a.m. EDT on Wednesday the center of Hurricane Laura was located at latitude 26.4°N and longitude 91.4°W which put it about 280 miles (450 km) south-southeast of Lake Charles, Louisiana.  Laura was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 963 mb.

A Hurricane Warning was in effect for the portion of the coast from San Luis, Pass, Texas to Intracoastal City, Lousiana.  Tropical Storm Warnings were in effect for the portions of the coast from Sargent, Texas to San Luis Pass and from Intracoastal City to the Mouth of the Mississippi River.

Hurricane Laura strengthened rapidly over the warm water in the Central Gulf of Mexico during the overnight hours.  An eye with a diameter of 30 miles (50 km) formed at the center of Laura.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Hurricane Laura.   Storms near the core were generating strong upper level divergence which was pumping large quantities of mass away from the hurricane in all directions.  The removal of mass allowed the surface pressure to decrease quickly, which caused Laura to rapidly intensify.

The size of the circulation around Hurricane Laura also increased during the overnight hours.  Winds to hurricane force extended out 70 miles (110 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 Laura was 20.6.  The Hurricane Size Index (HSI) was 19.1 and the Hurricane Wind Intensity Size Index (HWISI) was 39.7.  Hurricane Laura was capable of causing widespread major damage.

Hurricane Laura will continue to move through an environment favorable for intensification today.  Laura will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will little vertical wind shear.  Hurricane Laura could strengthen to Category 4 on the Saffir-Simpson Scale.  When Hurricane Laura approaches the coast it will get closer to an upper level trough over Texas and Oklahoma.  The trough will produce southwesterly winds which will blow toward the top of Laura.  Those winds will cause some vertical wind shear and Hurricane Laura could start to weaken just before it makes landfall.

Hurricane Laura will move around the western end of a subtropical high pressure system that extends from the Atlantic Ocean over the Gulf of Mexico.  Laura will move toward the north-northwest as it approaches the western end of the high.  On its anticipated track Hurricane Laura will make landfall near the border between Louisiana and Texas tonight.

Hurricane Laura will be capable of causing major damage over western Louisiana and eastern Texas.  Strong winds could cause widespread power outages.  Wind blowing water toward the coast will cause a storm surge of 10 to 15 feet (3 to 5 meters) near and to the east of where the center makes landfall.  Laura will drop locally heavy rain when it moves inland and flash floods could occur in some locations.

The wind speed in Hurricane Laura will be similar to the winds in Hurricane Harvey when Harvery made landfall on the coast of Texas in 2017.  Laura will be bigger than Harvey was.  The winds in Hurricane Laura could be stronger than the winds were in Hurricane Rita when Rita hit the same area in 2005.  However, Rita had intensified to Category 5 on the Saffir-Simpson Scale, but it was weakening when it made landfall.  Laura will not be as big as Rita was in 2005.

Hurricane Laura Strengthens over Central Gulf of Mexico

Hurricane Laura strengthened over the central Gulf of Mexico on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Laura was located 25.2°N and longitude 89.5°W which put it about 405 miles (655 km) southeast of Lake Charles, Louisiana.  Laura was moving toward the west-northwest at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 110 m.p.h. (175 km/h).  The minimum surface pressure was 978 mb.

A Hurricane Warning was in effect for the portion of the coast from San Luis Pass, Texas to Intracoastal City, Louisana.  Tropical Storm Warnings were in effect for the portions of the coast from Sargent to San Luis Pass, Texas and from Intracoastal City, Louisiana to the Mouth of the Mississippi River.  A Tropical Storm Warning was also in effect for Houston, Texas.

Hurricane Laura intensified over the warm water in the central Gulf of Mexico on Tuesday night.  An eye was visible intermittently on satellite imagery.  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 Laura.  Storms near the core generated upper level divergence which pumped mass away from the hurricane.  The removal of large quantities of mass was causing the pressure to decrease more rapidly.

The area of Laura with hurricane force winds expanded on Tuesday night.  Hurricane force winds 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 Laura was 13.9.  The Hurricane Size Index (HSI) was 13.7 and the Hurricane Wind Intensity Size Index (HWISI) was 27.6.

Hurricane Laura will move through an environment favorable for intensification on Wednesday.  Laura will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Laura will strengthen on Wednesday and it could intensify rapidly.  Laura will strengthen into a major hurricane and it could reach Category 4 on the Saffir-Simpson Scale.

Hurricane Laura will move around the western end of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Laura toward the northwest during the next 12 to 18 hours.  The hurricane will turn toward the north when it reaches the western end of the high.  On its anticipated track Hurricane Laura will landfall near the border between Louisiana and Texas on Wednesday night.

Hurricane Laura will be a major hurricane when it makes landfall.  It will be capable of causing regional major wind damage.  Hurricane Laura will also cause a storm surge of 10 to 15 feet (3 to 5 meters) near and to the east of where the center makes landfall.  Locally heavy rain could cause flash floods in parts of east Texas and Louisiana when Hurricane Laura moves inland.

Typhoon Bavi Passes East of Shanghai

Typhoon Bavi passed east of Shanghai on Tuesday.  At 5:00 p.m. EDT on Tuesday the center of Typhoon Bavi was located at latitude 31.9°N and longitude 124.7°E which put it about 200 miles (320 km) east-northeast of Shanghai, China.  Bavi was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 958 mb.

The circulation around Typhoon Bavi was well organized on Tuesday.  A circular eye with a diameter of 18 miles (30 km) was at the center of Bavi.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Typhoon Bavi.  Storm near the core generated upper level divergence which pumped mass away to the north of the typhoon.

The circulation around Typhoon Bavi was moderately large.  Winds to typhoon force extended out 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Bavi was 19.2.  The Hurricane Size Index (HSI) was 16.0 and the Hurricane Wind Intensity Size Index (HWISI) was 35.2.  Typhoon Bavi was capable of causing regional serious damage.

Typhoon Bavi will move through an environment favorable for intensification during the next 12 hours.  Bavi will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Bavi could strengthen into the equivalent of a major hurricane during the next 12 hours.  In 12 hours Bavi will start to move over cooler water, which could end the chance for intensification.  In 24 hours Typhoon Bavi will approach the eastern part of an upper level trough over China.  The trough will produce strong southwesterly winds which will cause strong vertical wind shear.  The strong shear will cause Bavi to weaken more quickly.

Typhoon Bavi will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Bavi toward the north during the next 36 hours.  On its anticipated track Typhoon Bavi could approach the west coast of North Korea in about 24 hours.  Bavi will bring strong winds and locally heavy rain to North Korea and parts of northeastern China.

Genevieve Prompts Hurricane Warning for Baja California

A potential close approach of Hurricane Genevieve prompted the issuance of a Hurricane Warning for the southern tip of Baja California.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Genevieve was located at latitude 20.9°N and longitude 109.7°W which put it about 140 miles (225 km) south of the southern tip of Baja California.  Genevieve was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (220 km/h).  The minimum surface pressure was 959 mb.

A Hurricane Warning was in effect for the portion of the coast from Los Barriles to Todos Santos, Mexico.  A Tropical Storm Warning was in effect for the portion of the coast from Todos Santos to Cabo San Lazaro, Mexico.  A Tropical Storm Watch was in effect for the portion of the coast from Los Barriles to La Paz, Mexico.

Hurricane Genevieve continued to exhibit a well organized circulation.  A circular eye was present at the center of circulation.  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 Genevieve.  Storms near the core of the circulation were generating strong upper level divergence was pumping mass away from the hurricane.

Hurricane force winds extended out 35 miles (55 km) from the center of Genevieve.  Tropical Storm force winds extended out 140 miles (225 km) from the center of circulation.  The Hurricane Intensity Index (HII) for Hurricane Genevieve was 20.6.  The Hurricane Size Index (HSI) was 13.4 and the Hurricane Wind Intensity Size Index (HWISI) was 34.0.

Hurricane Genevieve will move through an environment less favorable for a major hurricane during the next few days.  Genevieve will move over water where the Sea Surface Temperatures are cooler than 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Genevieve is likely to weaken when the core starts to move over cooler water.

Hurricane Genevieve will move around the southwestern part of an ridge of high pressure over the southwestern U.S. and northern Mexico.  The ridge will Genevieve toward the north-northwest during the next 24 hours.  On its anticipated track the core of Hurricane Genevieve could be near the southern tip of Baja California in about 18 hours.  Genevieve will cause gusty winds over the southern part of Baja California.  It will also drop locally heavy rain which could cause flash floods.

Hurricane Genevieve Rapidly Intensifies to Cat. 4

Hurricane Genevieve rapidly intensified to Category 4 on the Saffir-Simpson Scale over the Eastern North Pacific Ocean.  At 8:00 a.m. EDT on Tuesday the center of Hurricane Genevieve was located at latitude 17.7°N and longitude 107.6°W which put it about 390 miles (630 km) south-southeast of the southern tip of Baja California.  Genevieve was moving toward the northwest a 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 150 m.p.h. (240 km/h).  The minimum surface pressure was 950 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Los Barriles to Todos Santos, Mexico.  Tropical Storm Watches were in effect for the portion of the coast from Los Barriles to La Paz and from Todos Santos to Sante Fe, Mexico.

Hurricane Genevieve continued to intensify rapidly during the past 24 hours and it reached Category 4 on the Saffir-Simpson Scale.  A circular eye with a diameter of 20 miles (32 km) formed at the center of Genevieve.  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 Genevieve.  Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane in all directions.

The circulation around Hurricane Genevieve increased in size during the past 24 hours.  Winds to hurricane force extended out 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Genevieve was 25.1.  The Hurricane Size Index (HSI) was 10.9 and the Hurricane Wind Intensity Size Index (HWISI) was 36.0.

Hurricane Genevieve will move through an environment very favorable for strong hurricanes during the next 24 hours.  Genevieve 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 Genevieve could strengthen further during the next 24 hours.  If a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could occur.  The eyewall replacement cycle would cause Hurricane Genevieve to weaken.

Hurricane Genevieve will move south of a ridge of high pressure over the southwestern U.S. and northern Mexico.  The high will steer Genevieve toward the northwest during the next several days.  On its anticipated track the center of Hurricane Genevieve will pass west of Baja California.  However, Genevieve could come close enough to the coast to bring tropical storm force winds and locally heavy rain to the southern portion of Baja California.  Locally heavy rain could cause flash floods in some locations.

Isaias Strengthens Back into a Hurricane

Isaias strengthened back into a hurricane on Monday evening.  At 9:00 p.m. EDT on Monday the center of Hurricane Isaias was located at latitude 33.1°N and longitude 78.8°W which put it about 55 miles (90 km) south-southeast of Myrtle Beach, South Carolina.  Isaias was moving toward the north-northeast at 18 m.p.h. (30 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 988 mb.

A Hurricane Warning was in effect for the portion of the coast from South Santee River, South Carolina to Surf City, North Carolina.  Tropical Storm Warnings were in effect for the portion of the coast from Edisto Beach to South Santee River, South Carolina and from Surf City, North Carolina to Stonington, Maine including Albemarle Sound, Pamlico Sound, Long Island, Long Island Sound, Block Island, Martha’s Vineyard, and Nantucket.  A Tropical Storm Watch was in effect for the portion of the coast from Stonington, to Eastport, Maine.

The circulation around Hurricane Isaias became much better organized on Monday afternoon.  A reconnaissance aircraft investigating Isaias found winds to hurricane force.  An elliptical eye developed at the center of Hurricane Isaias.  A broken ring of thunderstorms surrounded the elliptical eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Isaias.  The strongest rainbands were in the northern half of the circulation.  Bands in the southern half of Hurricane Isaias consisted primarily of showers and lower clouds.  Winds to hurricane force extended out 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extended out 125 miles (200 km) from the center.

The Hurricane Intensity Index (HII) for Hurricane Isaias was 12.7.  The Hurricane Size Index (HSI) was 15.3 and the Hurricane Wind Intensity Size Index (HWISI) was 28.0.  Hurricane Isaias was capable of causing regional minor damage.

The center of Hurricane Isaias will make landfall between Myrtle Beach, South Carolina and Southport, North Carolina during the next few hours.  Isaias will bring hurricane force winds to the portion of the coast from Myrtle Beach, South Carolina to Surf City, North Carolina.  It will generate a storm surge of 3 to 6 feet (1 to 2 meters) along the coast.  Hurricane Isaias will drop heavy rain over extreme eastern South Carolina, eastern North Carolina and eastern Virginia.  Heavy rain could cause flooding in some locations.

The center of Hurricane Isaias will pass just west of Norfolk, Virginia on Tuesday morning.  isaias will weaken when it passes over land, but it will still bring gusty winds over eastern Virginia.  Isaias will pass near New York City on Tuesday evening and it will bring gusty winds to New England on Tuesday night.  Isaias could cause widespread power outages along the East Coast of the U.S.  It will also drop heavy rain east of the Appalachians and flash floods could occur in that region.

Typhoon Hagupit Makes Landfall in China

Typhoon Hagupit made landfall in China on Monday.  At 5:00 p.m. EDT on Monday the center of Typhoon Hagupit was located at latitude 28.3°N and longitude 120.8°E which put it about 50 miles (80 km) south-southwest of Taizhou, China and about 235 miles (375 km) south of Shanghai.  Hagupit was moving toward the north-northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 978 mb.

Former Tropical Storm Hagupit strengthened quickly to a typhoon before it made landfall on the east coast of China.  A circular eye formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storm.  Winds to typhoon force extended out 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extended out 135 miles (220 km) from the center.

The Hurricane Intensity Index (HII) for Typhoon Hagupit was 11.5.  The Hurricane Size Index (HSI) was 12.0 and the Hurricane Wind Intensity Size Index (HWISI) was 23.5.  Typhoon Hagupit was capable of causing regional minor damage.

Typhoon Hagupit will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean.  The high will steer Hagupit toward the north during the next 24 hours.  On its anticipated track the center of Typhoon Hagupit will pass west of Shanghai in 18 to 24 hours.  Hagupit will bring gusty winds and locally heavy rain to Zhejiang and Jiangsu. Heavy rain could cause flash floods in some locations.  Typhoon Hagupit will also cause a storm surge along the coast of Zhejiang, Jiangsu and Shanghai Shi.

Tropical Cyclone Amphan Intensifies Into Equivalent of Cat. 5 Hurricane

Tropical Cyclone Amphan intensified into equivalent of a Category 5 hurricane on the Saffir-Simpson Scale over the Bay of Bengal on Monday.  At 5:00 a.m. EDT on Monday the center of Tropical Cyclone Amphan was located at latitude 13.9°N and longitude 86.5°E which put it about 635 miles (1025 km) south-southwest of Kolkata, India.  Amphan was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 195 m.p.h. (315 km/h).  The minimum surface pressure was 909 mb.

The circulation around Tropical Cyclone Amphan appeared to develop a concentric eyewall structure on Monday.  The inner end of a rainband wrapped around the original small eye and eyewall.  The inner eye had a diameter of 10 miles (16 km).  A ring of strong thunderstorms surrounded the inner eye and the strongest winds were occurring in that ring of storms.  An outer eyewall with a diameter of 50 mile (80 km) surrounded the inner eye.    Bands of showers and thunderstorms were revolving around the concentric eyewalls.  Storms in the core of Amphan were generating strong upper level divergence which was pumping mass away from the tropical cyclone in all directions.

Tropical Cyclone Amphan had a large circulation.  Winds to hurricane/typhoon force extended out 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out 200 miles (325 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Amphan was 35.0.  The Hurricane Size Index (HSI) was 16.5 and the Hurricane Wind Intensity Size Index (HWISI0 was 51.5.  Tropical Cyclone Amphan was capable of causing catastrophic damage.

Tropical Cyclone Amphan will move through an environment very favorable for a strong tropical cyclone during the next 36 hours.  Amphan will move over water where the Sea Surface Temperature is near 31°C.  It will move under an upper level ridge where the upper level winds are weak.  There will be little vertical wind shear.  The eyewall replacement cycle will stop the intensification of Tropical Cyclone Amphan.  Amphan will weaken, at least temporarily, when the inner eyewall dissipates.  When that occurs the strongest winds will be occurring in the outer eyewall.  The eyewall replacement cycle could cause the circulation to increase in size.

Tropical Cyclone Amphan will move around the western end of a high pressure system over Southeast Asia.  The high will steer Amphan toward the north-northeast.  On its anticipate track the center of Tropical Cyclone Amphan will approach the coast around the northern Bay of Bengal in 36 hours.  Amphan will be a large dangerous tropical cyclone when it approaches the coast.  Tropical Cyclone Amphan will generate a significant storm surge along the coast of Bangladesh.  Amphan will cause major wind damage.  It will drop locally heavy rain over northeast India and Bangladesh.  Freshwater flooding will occur.

Tropical Cyclone Amphan Rapidly Intensifies Into Equivalent of Major Hurricane

Tropical Cyclone Amphan rapidly intensified into the equivalent of a major hurricane over the Bay of Bengal on Sunday night.  At 11:00 p.m. EDT on Sunday the center of Tropical Cyclone Amphan was located at latitude 13.3°N and longitude 86.4°E which put it about 675 miles (1090 km) south-southwest of Kolkata, India.  Amphan was moving toward the north at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 150 m.p.h. (240 km/h) and there were wind gusts to 185 m.p.h. (295 km/h).  The minimum surface pressure was 919 mb.

Tropical Cyclone Amphan rapidly intensified into a large powerful tropical cyclone on Sunday night.  A small circular eye was at the center of circulation.  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 Amphan.  Storms near the core were generating strong upper level divergence which was pumping mass away from the tropical cyclone in all directions.

The circulation around Tropical Cyclone Amphan grew in size on Sunday.  Winds to hurricane/typhoon force extended out 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out 210 miles (335 km) from the center.  The Hurricane Intensity Index (HII) for Tropical Cyclone Amphan was 31.6.  The Hurricane Size Index was 16.8 and the Hurricane Wind Intensity Size Index (HWISI) was 48.4.  Tropical Cyclone Amphan was capable of causing widespread significant damage.

Tropical Cyclone Amphan will remain in an environment capable of supporting a strong tropical cyclone during the next 36 to 48 hours.  Amphan will move over water where the Sea Surface Temperature is near 31°C.  It will move under an upper level ridge.  The upper level wind will be weak and there will be little vertical wind shear.  The ridge will actually enhance the upper level divergence.  If a rainband wraps around the existing eye and eyewall, then an eyewall replacement cycle could cause Tropical Cyclone Amphan to weaken.  Tropical Cyclone Amphan is likely to remain a large, powerful tropical cyclone during the next 48 hours.

Tropical Cyclone Amphan will move around the western end of a high pressure system over Southeast Asia.  The high will steer Amphan toward the north.  On its anticipated track Tropical Cyclone Amphan could approach the coast of Bangladesh in 48 hours.  Amphan is could still be the equivalent of a major hurricane when it reaches Bangladesh.  Tropical Cyclone Amphan could generate a significant storm surge at the coast.  Amphan will cause major wind damage and heavy rain could cause freshwater flooding.