Monthly Archives: August 2024

Hurricane Ernesto Intensifies to Cat. 2

Hurricane Ernesto intensified to Category 2 on the Saffir-Simpson Scale on Thursday evening.  At 11:00 p.m. EDT on Thursday the center of Hurricane Ernesto was located at latitude 27.1°N and longitude 68.1°W which put the center about 410 miles (660 km) south-southwest of Bermuda.  Ernesto was moving toward the north-northeast at 14 m.p.h. (22 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 968 mb.

A Hurricane Warning was in effect for Bermuda.

A U.S. Air Force Reserve Hurricane Hunter aircraft found that Hurricane Ernesto has strengthened to Category 2 on the Saffir-Simpson Scale on Thursday evening.  A circular eye with a diameter of 45 miles (75 km) was present at the center of Ernesto’s circulation.  The eye was surrounded by a broken 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 Ernesto’s circulation.  Storms near the center generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the pressure to decrease.

The size of the circulation around Hurricane Ernesto increased on Thursday.  Winds to hurricane force extended out 60 miles (95 km) from the center of Ernesto’s circulation.  Winds to tropical storm force extended out 260 miles (420 km) from the center of Hurricane Ernesto.

The Hurricane Intensity Index (HII) was 16.5.  The Hurricane Size Index (HSI) was 16.7 and the Hurricane Wind Intensity Size Index (HWISI) was 33.2.  Hurricane Ernesto was similar in intensity to Hurricane Idalia when Idalia hit Florida in 2023.  Ernesto is larger than Idalia was.

Hurricane Ernesto will move through an environment favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are 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 Ernesto is likely to continue to intensify during the next 24 hours.

Hurricane Ernesto will move around the western side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer Ernesto toward the north during the next 24 hours.  On its anticipated track, Hurricane Ernesto will approach Bermuda on Friday night.  The center of Ernesto will be near Bermuda on Saturday morning.

Hurricane Ernesto will bring strong winds and heavy rain to Bermuda.  The strong winds will be capable of causing serious damage.  Heavy rain could cause flash floods.

 

Typhoon Ampil Strengthens to Equivalent of a Major Hurricane

Typhoon Ampil strengthened to the equivalent of a major hurricane south of Tokyo on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Typhoon Ampil was located at latitude 33.0°N and longitude 140.9°E which put the center about 205 miles (330 km) south-southeast of Tokyo, Japan.  Ampil was moving toward the north 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. (230 km/h).  The minimum surface pressure was 951 mb.

A large circular eye was present at the center of Typhoon Ampil.  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 revolved around the core of Ampil’s circulation.  Storms near the core generated upper level divergence that pumped mass away from the typhoon.  The removal of mass caused the surface pressure to decrease.

The circulation around Typhoon Ampil was large.  Winds to typhoon force extended out 50 miles (80 km) from the center of Ampil’s circulation.  Winds to tropical storm force extended out 180 miles (290 km) from the center of Typhoon Ampil.

The Hurricane Intensity Index (HII) for Typhoon Ampil was 20.6.  The Hurricane Size Index (HSI) was 17.1 and the Hurricane Wind Intensity Size Index (HWISI) was 37.7.  Typhoon Ampil was similar in intensity to Hurricane Delta when Delta hit Louisiana in 2020.  Ampil is bigger than Delta was.

Typhoon Ampil will move through an environment favorable for intensification during the next 12 hours.  Ampil will move over water where the Sea Surface Temperatures are near 30°C. It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Ampil could continue to intensify during the next 12 hours.  Ampil Will move into an area where there are stronger westerly winds in the upper level within 24 hours.  Those stronger winds will cause the vertical wind shear to increase.  Typhoon Ampil will start to weaken when the wind shear increases.

Typhoon Ampil will move around the western side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Ampil toward the north during the next 12 hours.  On its anticipated track, Typhoon Ampil will be near the coast of central Honshu just to the southeast of Tokyo in 12 hours.  Ampil will start to move toward the east when it reaches the westerly winds in the upper levels.

Typhoon Ampil will bring strong winds and locally heavy rain to the coast of central Honshu south and east of Tokyo.  Strong winds will be capable of causing serious damage.  Heavy rain could cause flash floods in some locations.

 

Hurricane Ernesto Churns Toward Bermuda

Hurricane Ernesto churned toward Bermuda on Thursday.  At 2:00 p.m. EDT on Thursday the center of Hurricane Ernesto was located at latitude 25.4°N and longitude 69.3°W which put the center about 550 miles (885 km) south-southwest of Bermuda.  Ernesto was moving toward the north at 14 m.p.h. (22 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 974 mb.

A Hurricane Warning was in effect for Bermuda.

Hurricane Ernesto continued to strengthen gradually on Thursday.  The inner end of a rainband wrapped around the center of Ernesto’s circulation several times.  However, dry air spiraled into the center of Hurricane Ernesto each time and an eyewall failed to form.  Bands of showers and thunderstorms were revolving around the center of Ernesto’s circulation.  Storms near the center of Ernesto generated upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease gradually.

The size of the circulation around Hurricane Ernesto increased on Thursday.  Winds to hurricane force extended out 60 miles (95 km) from the center of Ernesto’s circulation.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Ernesto’s circulation.

Hurricane Ernesto will move through an environment favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are 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 Ernesto will intensify during the next 24 hours.

Hurricane Ernesto will move around the western side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer Ernesto toward the north during the next 24 hours.  On its anticipated track, Hurricane Ernesto will approach Bermuda on Friday night.

 

Ernesto Prompts Hurricane Watch for Bermuda

The risk posed by Hurricane Ernesto prompted the issuance of a Hurricane Watch for Bermuda.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Ernesto was located at latitude 23.0°N and longitude 68.9°W which put the center about 690 miles (1110 km) south-southwest of Bermuda.  Ernesto was moving toward the north-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (150 km/h).  The minimum surface pressure was 982 mb.

A Hurricane Watch was in effect for Bermuda.

Hurricane Ernesto continued to strengthen gradually on Wednesday evening.  The inner end of a rainband wrapped around the center of Ernesto’s circulation.  A circular eye appeared intermittently on satellite images.  The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms.  Other bands of showers and thunderstorms revolved around the center of Hurricane Ernesto.  Storms near the center of Ernesto generated upper level divergence that pumped mass away the hurricane.  The removal of mass caused the surface pressure to decrease.

Winds to hurricane force extended out 45 miles (75 km) in the eastern side of Hurricane Ernesto.  Winds to tropical storm force extended out 175 miles (280 km) from the center of Ernesto’s circulation.

Hurricane Ernesto will move through an environment favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are 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 Ernesto will intensify during the next 24 hours.

Hurricane Ernesto will move around the western side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer Ernesto toward the north during the next 24 hours.  On its anticipated track, Hurricane Ernesto will approach Bermuda on Friday night.

 

Ernesto Strengthens to a Hurricane Northwest of Puerto Rico

Former Tropical Storm Ernesto strengthened to a hurricane northwest of Puerto Rico on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Hurricane Ernesto was located at latitude 20.5°N and longitude 70.6°W which put the center about 175 miles (285 km) northwest of San Juan, Puerto Rico.  Ernesto was moving toward the northwest at 16 m.p.h. (26 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 991 mb.

Tropical Storm Warnings were in effect for the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Culebra and Vieques.

A U.S. Air Force Reserve Hurricane Hunter aircraft found that formed Tropical Storm Ernesto had strengthened to a hurricane northwest of Puerto Rico on Wednesday morning.  The inner end of a rainband wrapped around the center of Ernesto’s circulation.  An eye appeared to be forming at the center of Hurricane Ernesto.  Bands of showers and thunderstorms were revolving around the center of Ernesto.  Storms near the center of circulation generated upper level divergence that pumped mass away from the hurricane.

Winds to hurricane force extended out 30 miles (50 km) in the northeastern quadrant of Hurricane Ernesto.  Winds to tropical storm force extended out 230 miles (370 km) from the center of Ernesto’s circulation.

Hurricane Ernesto will move through an environment favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are 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 Ernesto will intensify during the next 24 hours.

Hurricane Ernesto will move around the western side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer Ernesto toward the north-northwest during the next 24 hours.  On its anticipated track, Hurricane Ernesto will move away from Puerto Rico.  Ernesto could approach Bermuda on Friday night.

Ampil Strengthens to a Typhoon South of Japan

Former Tropical Storm Ampil strengthened to a typhoon south of Japan on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Typhoon Ampil was located at latitude 28.0°N and longitude 141.1°E which put the center about 540 miles (870 km) south of Tokyo, Japan.  Ampil was moving toward the north-northeast at 9 m.p.h. (15 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 974 mb.

Former Tropical Storm Ampil strengthened to a typhoon south of Japan on Wednesday morning.  A small circular eye formed at the center of Typhoon Ampil’s circulation.  A ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms were revolving around the center of Typhoon Ampil.  Storms near the center generated upper level divergence that pumped mass away from the typhoon.

Winds to typhoon force extended out 45 miles (75 km) from the center of Ampil’s circulation.  Winds to tropical storm force extended out 185 miles (295 km) from the center of Typhoon Ampil.

Typhoon Ampil will move through an environment favorable for intensification during the next 24 hours.  Ampil will move over water where the Sea Surface Temperatures are near 30°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  Typhoon Ampil will intensify during the next 24 hours.  Ampil could intensify rapidly at times.  Typhoon Ampil could strengthen to the equivalent of a major hurricane within 36 hours.

Typhoon Ampil will move around the western side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Ampil toward the north during the next 24 hours.  On its anticipated track, Typhoon Ampil will be near the coast of central Honshu in 48 hours.

 

Tropical Storm Ernesto Brings Wind and Rain to the Leeward Islands

Tropical Storm Ernesto brought wind and rain to the Leeward Islands on Tuesday morning.  At 8:00 a.m. EDT on Tuesday the center of Tropical Storm Ernesto was located at latitude 16.6°N and longitude 61.9°W which put the center about 35 miles (55 km) northwest of Guadeloupe.  Ernesto was moving toward the west at 18 m.p.h. (30 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 1005 mb.

Tropical Storm Warnings were in effect for Guadeloupe, St. Martin, St. Barthelemy, St, Kitts, Nevis, Montserrat, Antigua, Barbuda, Anguilla, Saba, St. Eustatius, Sint Maarten, the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Culebra, Vieques.

More thunderstorms formed near the center of Tropical Storm Ernesto on Tuesday morning.  Those thunderstorms generated more upper level divergence that removed mass from the tropical storm.  The removal of more mass cause the surface pressure to decrease.  More thunderstorms also developed in bands revolving around the center of Ernesto’s circulation

The strongest winds were occurring in the northern side of Tropical Storm Ernesto.  Winds to tropical storm force extended out 70 miles (110 km) in the northern side of Ernesto’s circulation.  The winds in the southern part of Ernesto were blowing at less than tropical storm force.

Tropical Storm Ernesto will move through an environment favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over the subtropical Atlantic Ocean.  The ridge will produce easterly winds that will blow toward the top of Ernesto’s circulation. Those winds will cause some vertical wind shear, but the wind shear will not be enough to prevent intensification.  Tropical Storm Ernesto will intensify during the next 24 hours.

Tropical Storm Ernesto will move around the southern side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer the tropical wave quickly toward the west-northwest during the next 24 hours.  On its anticipated track, Tropical Storm Ernesto will reach Puerto Rico on Tuesday night.

Tropical Storm Ernesto will bring gusty winds and locally heavy rain to the Leeward Islands, the British Virgin Islands, the U.S. Virgin Islands and Puerto Rico.  Heavy rain is likely to cause flash floods in some locations.  The winds could be strong enough to cause localized outages of electricity.  Ernesto could also cause a storm surge of up to 4 feet (1 meter).

 

 

Tropical Storm Ampil Forms South of Japan

Tropical Storm Ampil formed over the Western North Pacific Ocean south of Japan on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Ampil was located at latitude 24.7°N and longitude 138.1°E which put the center about 760 miles (1225 km) south of Tokyo, Japan.  Ampil was moving toward the northeast 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 992 mb.

A low pressure system over the Western North Pacific Ocean south of Japan strengthened on Monday afternoon and the Japan Meteorological Agency designated the system as Tropical Storm Ampil.  More thunderstorms developed near the center of Ampil’s circulation.  The inner end of a rainband wrapped part of the way around the center of Tropical Storm Ampil.  Other bands of showers and thunderstorms were revolving around the center of circulation.  Storms near the center generated upper level divergence that pumped mass away from the tropical storm.  The removal of mass caused the surface pressure to decrease.

Tropical Storm Ampil will move through an environment favorable for intensification during the next 24 hours.  Ampil will move over water where the Sea Surface Temperatures are near 30°C.  It will move under a small upper level ridge that is in between and upper level low southwest of Japan and an upper level low east of Japan.  The upper level winds are weak in the small ridge and there will be little vertical wind shear.  Tropical Storm Ampil will intensify during the next 24 hours.  Ampil could intensify rapidly at times.  Tropical Storm Ampil is likely to strengthen to a typhoon within 36 hours.

Tropical Storm Ampil will move around the western side of a high pressure system over the Western North Pacific Ocean.  The high pressure system will steer Ampil toward the north during the next 24 hours.  On its anticipated track, Tropical Storm Ampil will move closer to central Honshu.

Elsewhere over the Western North Pacific Ocean, former Tropical Storm Maria weakened to a tropical depression over the Sea of Japan, and a subtropical cyclone east of Japan made a transition to Tropical Storm Son-tinh.

At 5:00 p.m. EDT on Monday the center of Tropical Depression Maria was located at latitude 41.0°N and longitude 138.7°E which put the center about 100 miles (160 km) west-southwest of Aomori, Japan.  Maria was moving toward the north-northwest at 9 m.p.h. (15 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 999 mb.

At 5:00 p.m. EDT on Monday the center of Tropical Storm Son-tinh was located at latitude 3.7°N and longitude 149.0°E which put the center about 560 miles (905 km) east of Tokyo, Japan. Son-tinh was moving toward the northwest at 15 m.p.h. (24 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 993 mb.

 

Tropical Storm Ernesto Forms East of the Leeward Islands

Tropical Storm Ernesto formed east of the Leeward Islands on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Storm Ernesto was located at latitude 16.0°N and longitude 57.5°W which put the center about 295 miles (475 km) east-southeast of Antigua.  Ernesto was moving toward the west-northwest at 28 m.p.h. (44 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 1009 mb.

Tropical Storm Warnings were in effect for Guadeloupe, St. Martin, St. Barthelemy, St, Kitts, Nevis, Montserrat, Antigua, Barbuda, Anguilla, Saba, St. Eustatius, Sint Maarten, the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Culebra, Vieques.

A U.S. Air Force Reserve Hurricane Hunter aircraft found a distinct low level center of circulation in a tropical wave previously designated as Potential Tropical Cyclone Five, and the U.S. National Hurricane Center designated the system as Tropical Storm Ernesto.

More thunderstorms formed near the center of Tropical Storm Ernesto.  Bands of showers and thunderstorms began to revolve around the center of Ernesto’s circulation.  Storms near the center of Ernesto started to generate upper level divergence that pumped mass away from the tropical storm.

The reconnaissance plane also found that tropical storm force winds extended out 60 miles (95 km) in the northeastern quadrant of Tropical Storm Ernesto.  The winds in the other parts of Ernesto’s circulation were blowing at less than tropical storm force.

Tropical Storm Ernesto will move through an environment somewhat favorable for intensification during the next 24 hours.  Ernesto will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over the subtropical Atlantic Ocean.  The ridge will produce strong easterly winds that will blow toward the top of the tropical wave.  Those winds will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but the shear is not enough to stop intensification. Tropical Storm Ernesto is likely to intensify gradually during the next 24 hours.

Tropical Storm Ernesto will move around the southern side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer the tropical wave quickly toward the west-northwest during the next 24 hours.  On its anticipated track, ‘Tropical Storm Ernesto could reach the Leeward Islands early on Tuesday.  Ernesto could be near Puerto Rico on Tuesday night.

Tropical Storm Ernesto will bring gusty winds and locally heavy rain to the Leeward Islands, the British Virgin Islands, the U.S. Virgin Islands and Puerto Rico.  Heavy rain is likely to cause flash floods in some locations.  The winds could be strong enough to cause localized outages of electricity.  Ernesto could also cause a storm surge of up to 4 feet (1 meter).

 

Tropical Storm Warnings Issued for Leeward Islands, Virgin Islands and Puerto Rico

The potential risk posed by a tropical wave currently designated as Potential Tropical Cyclone Five prompted the issuance of Tropical Storm Warnings for the Leeward Islands, the Virgin Islands, and Puerto Rico on Monday morning.  At 11:00 a.m. EDT on Monday the center of Potential Tropical Cyclone Five was located at latitude 15.1°N and longitude 55.6°W which put the center about 435 miles (700 km) east-southeast of Antigua.  The tropical wave was moving toward the west at 26 m.p.h. (43 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 1010 mb.

Tropical Storm Warnings were in effect for Guadeloupe, St. Martin, St. Barthelemy, St, Kitts, Nevis, Montserrat, Antigua, Barbuda, Anguilla, Saba, St. Eustatius, Sint Maarten, the British Virgin Islands, the U.S. Virgin Islands, Puerto Rico, Culebra, Vieques.

A tropical wave east of the Lesser Antilles that is currently designated as Potential Tropical Cyclone Five exhibited more organization on Monday morning.  However, a NOAA aircraft investigating the tropical wave did not find a well defined low level center of circulation.  More thunderstorms formed near the axis of the tropical wave.  A large counterclockwise rotation associated with the tropical wave strengthened a little on Monday morning.  Bands of showers and thunderstorms appeared to be forming in parts of the tropical wave.

Potential Tropical Cyclone Five will move through an environment somewhat favorable for the formation of a tropical cyclone during the next 24 hours.  The tropical wave will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the southern part of an upper level ridge over the subtropical Atlantic Ocean.  The ridge will produce strong easterly winds that will blow toward the top of the tropical wave.  Those winds will cause moderate vertical wind shear.  The wind shear will slow the organization of the tropical wave into a tropical cyclone.  Potential Tropical Cyclone Five is likely to organize gradually into a tropical depression or a tropical storm during the next 24 hours.

Potential Tropical Cyclone Five will move around the southern side of a subtropical high pressure system over the Atlantic Ocean.  The high pressure system will steer the tropical wave quickly toward the west-northwest during the next 24 hours.  On its anticipated track, Potential Tropical Cyclone Five could approach the Leeward Islands on Monday night.  It could be near Puerto Rico on Tuesday night.

Potential Tropical Cyclone Five could be a tropical storm when it reaches the Leeward Islands.  It will bring gusty winds and locally heavy rain to the Leeward Islands, the British Virgin Islands, the U.S. Virgin Islands and Puerto Rico.  Heavy rain is likely to cause flash floods in some locations.  The winds could be strong enough to cause localized outages of electricity.