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Hurricane Isaac Strengthens to Cat. 2 West of the Azores

Hurricane Isaac strengthened to Category 2 on the Saffir-Simpson Scale over the North Atlantic Ocean west of the Azores on Saturday.  At 11:00 a.m. EDT on Saturday the center of Hurricane Isaac was located at latitude 40.2°N and longitude 39.7°W which put the center about 695 miles (1120 km) west-northwest of the Azores.  Isaac was moving toward the east-northeast at 20 m.p.h. (32 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 968 mb.

Even though Hurricane Isaac was at latitude 40°N, it intensified to a Category 2 hurricane on the Saffir-Simpson Scale on Saturday morning.  A circular eye was present at the center of Isaac’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 Hurricane Isaac.  Storms near the core of Isaac generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Isaac was reasonably symmetrical given it high latitude.  Winds to hurricane force extended out 45 miles (75 km) from the center of Isaac’s circulation.  Winds to tropical storm force extended out 200 miles (320 km) from the center of Hurricane Isaac.

Hurricane Isaac will move through an environment unfavorable for intensification during the next 24 hours.  Isaac will move over water where the Sea Surface Temperatures are near 24°C.  It will move under the eastern side of an upper level trough that is southeast of Greenland.  The upper level trough will produce strong southwesterly winds that will blow toward the top of Isaac’s circulation.  Those winds will cause the vertical wind shear to increase.  The combination of cooler water and stronger vertical wind shear will cause Hurricane Isaac to weaken during the next 24 hours.

The upper level trough southeast of Greenland will steer Hurricane Isaac toward the east-northeast during the next 24 hours.  On its anticipated track, Hurricane Isaac will pass northwest of the Azores on Sunday.

Elsewhere, the circulation of former Hurricane Helene was spinning down south of the Ohio River and Tropical Storm Joyce was churning east of the Northern Leeward Islands.

At 11:00 a.m. EDT on Saturday the center of Tropical Depression Helene was located at latitude 36.6°N and longitude 86.4°W which put the center about 50 miles (80 km) northwest of Nashville, Tennessee.  Helene was moving toward the east at 3 m.p.h. (5 km/h).  The maximum sustained wind speed was 15 m.p.h. (25 km/h) and there were wind gusts to 25 m.p.h. (40 km/h).  The minimum surface pressure was 968 mb.

At 11:00 a.m. EDT on Saturday the center of Tropical Storm Joyce was located at latitude 20.0°N and longitude 46.0°W which put the center about 1120 miles (1805 km) east of the Northern Leeward Islands.  Joyce was moving toward the northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 1004 mb.

Tropical Storm Helene Brings Heavy Rain and Floods to Southeast U.S.

Tropical Storm Helene brought heavy rain and floods to parts of the southeast U.S. on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Helene was located at latitude 35.1°N and longitude 83.8°W which put the center about 30 miles (50 km) southwest of Bryson City, North Carolina.  Helene was moving toward the north at 32 m.p.h. (52 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 975 mb.

A Tropical Storm Warning is in effect for the portion of the coast from Savannah River, Georgia to Little River Inlet, South Carolina.

Tropical Storm Warnings were also in effect for inland locations in South Carolina, eastern Georgia, western North Carolina and eastern Tennessee. 

Even though former Hurricane Helene weakened to a tropical storm as it moved over the southeastern U.S. on Friday, Helene still was dropping very heavy rain.  Heavy rain fell over parts of Georgia, South Carolina, western North Carolina, eastern Tennessee, and western Virginia.  The heavy rain caused rivers and streams to rise quickly in those areas and numerous flash flood and flood warnings were issued.

The Catawba River at Pleasant Gardens, North Carolina was at Record Flood level.  The Saluda River at Greenville, South Carolina was at Major Flood level.  The French Broad River at Blantyre, North Carolina was at Record Flood level.  The Pigeon River at Canton, North Carolina was at Record Flood level.  The Pigeon River at Newport, Tennessee was at Major Flood level.  The Swannanoa River at Biltmore, North Carolina was at Record Flood level.  Numerous other rivers and streams in the region were also flooding.  Many roads were impassible.

Over four million customers in Florida, Georgia, South Carolina and North Carolina were experiencing electricity outages.

Tropical Storm Helene will move around the eastern side of an upper level low over the middle Mississippi River Valley.  The upper level low will steer Helene toward the north during the next 24 hours.  The circulation around Tropical Storm Helene will gradually merge with the circulation around the upper level low.

Tropical Storm Helene will continue to drop heavy rain on the southern Appalachians.  the heavy rain is likely to cause additional flash floods.  Helene will also bring gusty winds as far north as southern and central Ohio on Friday afternoon and evening.

Elsewhere over the Atlantic Ocean, former Tropical Storm Isaac intensified to a hurricane west of the Azores and Tropical Storm Joyce formed east of the Northern Leeward Islands.

At 11:00 a.m. EDT on Friday the center of Hurricane Isaac was located at latitude 37.4°N and longitude 46.8°W which put the center about 1080 miles (1740 km) west of the Azores.  Isaac was moving toward the east-northeast at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 981 mb.

At 11:00 a.m. EDT on Friday the center of Tropical Storm Joyce was located at latitude 18.1°N and longitude 42.9°W which put the center about 1325 miles (2130 km) east of the Northern Leeward Islands.  Joyce was moving toward the northwest at 13 m.p.h. (20 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 1006 mb.

Hurricane Helene Makes Landfall in North Florida

The center of Hurricane Helene officially made landfall in North Florida on Thursday night.  The center of Helene crossed the coast of Florida near the mouth of the Aucilla River west-southwest of Perry.  At 11:00 p.m. EDT on Thursday the center of Hurricane Helene was located at latitude 29.9°N and longitude 83.9°W which put the center about 40 miles (65 km) southeast of Tallahassee, Florida and about 10 miles (15 km) west-southwest of Perry.  Helene was moving toward the north-northeast at 24 m.p.h. (39 km/h).  The maximum sustained wind speed was 140 m.p.h. (225 km/h) and there were wind gusts to 165 m.p.h. (265 km/h).  The minimum surface pressure was 938 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Mexico Beach to the Okaloosa/Walton County Line, Florida.  A Tropical Storm Warning is in effect for the portion of the coast from Flamingo, Florida to Little River Inlet, South Carolina.  A Tropical Storm Warning is in effect for Lake Okeechobee. 

Hurricane Helene intensified to Category 4 on the Saffir-Simpson Scale before it made landfall on the coast of Florida.  A circular eye with a diameter of 32 miles (52 km) was at the center of Helene’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 Hurricane Helene. Storms near the center of Helene generated strong upper level divergence that pumped large quantities of mass away from the hurricane. The removal of large quantities of mass was causing the surface pressure to decrease.

The circulation around Hurricane Helene was large. Winds to hurricane force extended out 60 miles (95 km) from the center of Helene’s circulation. Winds to tropical storm force extended out 310 miles (500 km) in the eastern side of Hurricane Helene.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Helene’s circulation.

The Hurricane Intensity Index (HII) is 28.3. The Hurricane Size Index (HSI) is 21.2 and the Hurricane Wind Intensity Size Index (HWISI) 49.5.  Hurricane Helene is stronger than Hurricane Irma was when Irma hit southwest Florida in 2017.  However, Helene is not quite as big as Irma was.

Hurricane Helene will move around the eastern side of an upper level trough over the Mississippi River Valley.  The upper level trough will steer Helene quickly toward the north during the next 24 hours.  On its anticipated track, Hurricane Helene will move across Georgia on Friday.

Hurricane Warnings are in effect for parts of northern Florida, southeastern Alabama and southwestern Georgia.  The Hurricane Warnings include Tallahassee, Florida and Macon, Georgia.

Tropical Storm Warnings are in effect for the Florida Peninsula, northwest Florida eastern Alabama, northern and eastern Georgia, all of South Carolina, southwestern North Carolina, and southeastern Tennessee.  The Tropical Storm Warnings include Atlanta, Georgia and Charleston, South Carolina.

Hurricane Helene will weaken gradually as it moves farther inland.  Hurricane Helene will bring strong winds and heavy rain to Georgia on Friday.  Heavy rain will also fall over the southern Appalachians.  Heavy rain is likely to cause flash floods.

Flood Watches are in effect for Florida, eastern Alabama, Georgia, western South Carolina, western North Carolina and eastern Tennessee.

Hurricane Helene will continue to cause a storm surge along the west coast of Florida during the next few hours.

A Storm Surge Warning is in effect for the portion of the coast from Mexico Beach to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

Hurricane Helene Strengthens to Cat. 4

Hurricane Helene strengthened to Category 4 on the Saffir-Simpson Scale on Thursday evening.  At 6:00 p.m. EDT on Thursday the center of Hurricane Helene was located at latitude 28.0°N and longitude 84.5°W which put the center about 165 miles (270 km) south of Tallahassee, Florida.  Helene was moving toward the north-northeast at 23 m.p.h. (37 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 947 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Mexico Beach to the Okaloosa/Walton County Line, Florida.  A Tropical Storm Warning is in effect for the portion of the coast from Flamingo, Florida to Little River Inlet, South Carolina.  A Tropical Storm Warning is in effect for Lake Okeechobee. 

A NOAA Hurricane Hunter aircraft found that Hurricane Helene was continuing to strengthen to on Thursday evening.  An eye with a diameter of 30 miles (48 km) was at the center of Helene’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 Hurricane Helene.  Storms near the center of Helene generated strong upper level divergence that pumped large quantities of mass away from the hurricane.  The removal of large quantities of mass was causing the surface pressure to decrease.

The circulation around Hurricane Helene was large.  Winds to hurricane force extended out 60 miles (95 km) from the center of Helene’s circulation.  Winds to tropical storm force extended out 345 miles (555 km) in the eastern side of Hurricane Helene.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Helene’s circulation.

The Hurricane Intensity Index (HII) is 25.1.  The Hurricane Size Index (HSI) is 23.6 and the Hurricane Wind Intensity Size Index (HWISI) 48.7.  Hurricane Helene is stronger than Hurricane Irma was when Irma hit southwest Florida in 2017.  However, Helene is not quite as big as Irma was.

Hurricane Helene will move through an environment favorable for intensification for the next few hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the eastern Gulf of Mexico.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear. Hurricane Helene could intensify a little more during the next few hours.

Hurricane Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the north-northeast during the next 24 hours.  On its anticipated track, Hurricane Helene will make landfall on the coast of northern Florida at Apalachee Bay Thursday evening.  Helene will be a major hurricane when it reaches the coast.

Hurricane Helene will be a major hurricane when it reaches northern Florida.  Helene will be a large and dangerous hurricane.  Hurricane Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.

Flood Watches are in effect for Florida, eastern Alabama, Georgia, western South Carolina, western North Carolina and eastern Tennessee.

Helene could also cause a storm surge of up to 20 feet (6.1 meters) along portions of the west coast of Florida.

A Storm Surge Warning is in effect for the portion of the coast from Mexico Beach to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

An upper level trough over the Mississippi River Valley will steer Hurricane Helene quickly toward the north-northeast after it makes landfall.  Since the circulation around Helene is so large, Hurricane Helene will produce hurricane force winds in inland locations as well.

Hurricane Warnings are in effect for parts of northern Florida, southeastern Alabama and southwestern Georgia.  The Hurricane Warnings include Tallahassee, Florida and Macon, Georgia.

Tropical Storm Warnings are in effect for the Florida Peninsula, northwest Florida eastern Alabama, northern and eastern Georgia, all of South Carolina, southwestern North Carolina, and southeastern Tennessee.  The Tropical Storm Warnings include Atlanta, Georgia and Charleston, South Carolina.

Hurricane Helene is likely to cause widespread electricity outages as it moves inland over the southeastern U.S.

Helene Intensifies to a Major Hurricane

Hurricane Helene intensified to a major hurricane over the eastern Gulf of Mexico on Thursday.  At 2:00 p.m. EDT on Thursday the center of Hurricane Helene was located at latitude 26.7°N and longitude 84.9°W which put the center about 205 miles (335 km) south of Apalachicola, Florida.  Helene was moving toward the north-northeast at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 959 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Mexico Beach to the Okaloosa/Walton County Line, Florida.  A Tropical Storm Warning is in effect for the portion of the coast from Flamingo, Florida to Little River Inlet, South Carolina.  A Tropical Storm Warning is in effect for Lake Okeechobee. 

A U.S. Air Force Hurricane Hunter aircraft found that Hurricane Helene had strengthened to a major hurricane on Thursday afternoon.  An eye with a diameter of 30 miles (48 km) was at the center of Helene’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 Hurricane Helene.  Storms near the center of Helene generated strong upper level divergence that pumped large quantities of mass away from the hurricane.

The circulation around Hurricane Helene was large.  Winds to hurricane force extended out 60 miles (95 km) from the center of Helene’s circulation.  Winds to tropical storm force extended out 345 miles (555 km) in the eastern side of Hurricane Helene.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Helene’s circulation.

The Hurricane Intensity Index (HII) is 22.1.  The Hurricane Size Index (HSI) is 17.6 and the Hurricane Wind Intensity Size Index (HWISI) 39.7.  Hurricane Helene is stronger than Hurricane Irma was when Irma hit southwest Florida in 2017.  However, Helene is not as big as Irma was.

Hurricane Helene will move through an environment favorable for intensification during the next few hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the eastern Gulf of Mexico.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Helene is likely to intensify during the next few hours.  Helene could strengthen to Category 4 on the Saffir-Simpson Scale.

Hurricane Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the north-northeast during the next 24 hours.  On its anticipated track, Hurricane Helene will make landfall on the coast of northern Florida at Apalachee Bay Thursday evening.  Helene will be a major hurricane when it reaches the coast.

Hurricane Helene will be a major hurricane when it reaches northern Florida.  Helene will be a large and dangerous hurricane.  Hurricane Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.

Flood Watches are in effect for Florida, eastern Alabama, Georgia, western South Carolina, western North Carolina and eastern Tennessee.

Helene could also cause a storm surge of up to 20 feet (6.1 meters) along portions of the west coast of Florida.

A Storm Surge Warning is in effect for the portion of the coast from Mexico Beach to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

An upper level trough over the Mississippi River Valley will steer Hurricane Helene quickly toward the north-northeast after it makes landfall.  Since the circulation around Helene is so large, Hurricane Helene will produce hurricane force winds in inland locations as well.

Hurricane Warnings are in effect for parts of northern Florida, southeastern Alabama and southwestern Georgia.  The Hurricane Warnings include Tallahassee, Florida and Macon, Georgia.

Tropical Storm Warnings are in effect for the Florida Peninsula, northwest Florida eastern Alabama, northern and eastern Georgia, all of South Carolina, southwestern North Carolina, and southeastern Tennessee.  The Tropical Storm Warnings include Atlanta, Georgia and Charleston, South Carolina.

Hurricane Helene is likely to cause widespread electricity outages as it moves inland over the southeastern U.S.

Hurricane Helene Strengthens to Cat. 2

Hurricane Helene strengthened to Category 2 on the Saffir-Simpson Scale over the eastern Gulf of Mexico on Thursday morning.  At 8:00 a.m. EDT on Thursday the center of Hurricane Helene was located at latitude 24.5°N and longitude 85.9°W which put the center about 365 miles (585 km) south of Apalachicola, Florida.  Helene was moving toward the north-northeast at 12 m.p.h. (19 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 960 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.  .

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Mexico Beach to the Okaloosa/Walton County Line, Florida.  A Tropical Storm Warning is in effect for the portion of the coast from Flamingo, Florida to Little River Inlet, South Carolina.  A Tropical Storm Warning is in effect for Lake Okeechobee.  A Tropical Storm Warning was also in effect for the Cuban provinces of Artemisa, Pinar del Rio and Isle of Youth.

A U.S. Air Force Hurricane Hunter aircraft found that Hurricane Helene had strengthened to Category 2 on the Saffir-Simpson Scale on Thursday morning.  An eye with a diameter of 30 miles (48 km) was at the center of Helene’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 Hurricane Helene.  Storms near the center of Helene generated strong upper level divergence that pumped large quantities of mass away from the hurricane.  The removal of large amounts of mass caused the surface pressure to decrease rapidly.

The circulation around Hurricane Helene was large.  Winds to hurricane force extended out 60 miles (95 km) from the center of Helene’s circulation.  Winds to tropical storm force extended out 345 miles (555 km) in the eastern side of Hurricane Helene.  Winds to tropical storm force extended out 140 miles (225 km) in the western side of Helene’s circulation.

The Hurricane Intensity Index (HII) is 16.5.  The Hurricane Size Index (HSI) is 17.6 and the Hurricane Wind Intensity Size Index (HWISI) 34.1.  Hurricane Helene is similar in intensity to Hurricane Idalia that hit northeast Florida in 2023.  However, Helene is much bigger than Idalia was.  Helene is still intensifying.  So, Helen will be stronger than Idalia was when i reaches the coast.

Hurricane Helene will move through an environment favorable for intensification during the next 12 hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the eastern Gulf of Mexico.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Helene will intensify during the next 12 hours.  Helene is likely to strengthen to a major hurricane by Thursday afternoon.  Helene could intensify rapidly at times.

Hurricane Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the north-northeast during the next 24 hours.  On its anticipated track, Hurricane Helene will make landfall on the coast of northern Florida at Apalachee Bay Thursday evening.  Helene is likely to be a major hurricane when it reaches the coast

Hurricane Helene is likely to be a major hurricane when it reaches northern Florida.  Helene will be a large and dangerous hurricane.  Hurricane Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.

Flood Watches are in effect for Florida, eastern Alabama, Georgia, western South Carolina, western North Carolina and eastern Tennessee.

Helene could also cause a storm surge of up to 20 feet (6.1 meters) along portions of the west coast of Florida.

A Storm Surge Warning is in effect for the portion of the coast from Mexico Beach to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

An upper level trough over the Mississippi River Valley will steer Hurricane Helene quickly toward the north-northeast after it makes landfall.  Since the circulation around Helene is so large, Hurricane Helene will produce hurricane force winds in inland locations as well.

Hurricane Warnings are in effect for parts of northern Florida, southeastern Alabama and southwestern Georgia.  The Hurricane Warnings include Tallahassee, Florida and Macon, Georgia.

Tropical Storm Warnings are in effect for the Florida Peninsula, northwest Florida eastern Alabama, northern and eastern Georgia, all of South Carolina, southwestern North Carolina, and southeastern Tennessee.  The Tropical Storm Warnings include Atlanta, Georgia and Charleston, South Carolina.

Hurricane Helene is likely to cause widespread electricity outages as it moves inland over the southeastern U.S.

Helene Strengthens to a Hurricane

Former Tropical Storm Helene strengthened to a hurricane northeast of the Yucatan Peninsula on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Hurricane Helene was located at latitude 21.6°N and longitude 86.3°W which put the center about 500 miles (810 km) south-southwest of Tampa, Florida.  Helene was moving toward the north-northwest at 10 m.p.h. (16 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 979 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.  A Hurricane Warning is in effect for the portion of the coast from Cabo Catoche to Tulum, Mexico.  That Hurricane Warning includes Cancun and Cozumel.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.  A Hurricane Watch is also in effect for the Cuban province of Pinar del Rio.

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Mexico Beach to the Okaloosa/Walton County Line, Florida.  A Tropical Storm Warning is in effect for the portion of the coast from Flamingo, Florida to South Santee River, South Carolina.  A Tropical Storm Warning is in effect for Lake Okeechobee.  A Tropical Storm Warning is in effect for the portion of the coast from Rio Lagartos to Cabo Catoche, Mexico. A Tropical Storm Warning was also in effect for the Cuban provinces of Artemisa, Pinar del Rio and Isle of Youth.

A Tropical Storm Watch is in effect for the portion of the coast from South Santee River to Little River Inlet, South Carolina.

A U.S. Air Force Reserve Hurricane Hunter aircraft found that former Tropical Storm Helene had strengthened to a hurricane on Wednesday morning.  The inner end of a rainband wrapped around the northern, western and southern sides of the center of Helene’s circulation.  An eye appeared to be forming at the center of Hellene.  Bands of showers and thunderstorms were revolving around the core of Hurricane Helene.  Storms near the core generated strong upper level divergence that pumped mass away from the hurricane.  The removal of mass caused the surface pressure to decrease.

Winds to hurricane force extended out 25 miles (40 km) from the center of Hurricane Helene.  Winds to tropical storm force extended out 275 miles (445 km) in the eastern side of Helene’s circulation.  Winds to tropical storm force extended out 105 miles (165 km) in the eastern side of Hurricane Helene.

Hurricane Helene will move through an environment favorable for intensification during the next 24 hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the western Gulf of Mexico and the northwestern Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Hurricane Helene will intensify during the next 24 hours.  Helene is likely to strengthen to a major hurricane by Thursday afternoon.  Helene could intensify rapidly after an inner core with an eye and an eyewall is fully developed.

Hurricane Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the north during the next 24 hours.  On its anticipated track, Hurricane Helene will approach northern Florida on Thursday afternoon.  Helene is likely to be a major hurricane when it reaches the northeastern Gulf of Mexico.

Hurricane Helene is likely to be a major hurricane when it approaches northern Florida on Thursday.  Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.

Flood Watches are in effect for Florida, eastern Alabama, and Georgia.

Helene could also cause a storm surge of up to 15 feet (4.5 meters) along portions of the west coast of Florida.

A Storm Surge Warning is in effect for the portion of the coast from Indian Pass to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

A Storm Surge Watch is in effect for the portion of the coast from Indian Pass to Mexico Beach, Florida.

Tropical Storm Helene Prompts Hurricane and Storm Surge Warnings for Florida

The risk posed by Tropical Storm Helene prompted the issuance of a Hurricane Warning and a Storm Surge Warning for the west coast of Florida.  At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Helene was located at latitude 19.7°N and longitude 84.7°W which put the center about 155 miles (250 km) east-southeast of Cozumel, Mexico.  Helene was moving toward the west-northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 50 m.p.h. (80 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 995 mb.

A Hurricane Warning is in effect for the portion of the coast from Anclote River to Mexico Beach, Florida.  A Hurricane Warning is in effect for the portion of the coast from Cabo Catoche to Tulum, Mexico.  That Hurricane Warning includes Cancun and Cozumel.

A Hurricane Watch is in effect for the portion of the coast from Anclote River to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.  A Hurricane Watch is also in effect for the Cuban province of Pinar del Rio.

A Tropical Storm Warning is in effect for the portion of the coast from Anclote River to Flamingo, Florida.  The Tropical Storm Warning includes Tampa Bay.  A Tropical Storm Warning is in effect for the Lower and Middle Florida Keys west of Channel 5 Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Rio Lagartos to Cabo Catoche, Mexico. A Tropical Storm Warning was also in effect for the Cuban provinces of Artemisa, Pinar del Rio and Isle of Youth.

A Tropical Storm Watch is in effect for Lake Okeechobee.  A Tropical Storm Watch is in effect for the portion of the coast from the Palm Beach/Martin County Line, Florida to Savannah River, Georgia.

Tropical Storm Helene strengthened on Tuesday afternoon.  The center of Helene’s circulation was near NOAA buoy 42056.  The buoy measured a surface pressure of 996 mb.

The inner end of a rainband started to wrap around the center of Tropical Storm Helene.  More thunderstorms formed near the center of Helene’s circulation.  More thunderstorms also developed in bands in the western side of Tropical Storm Helene.  Storms near the center of Helene’s circulation generated more upper level divergence that pumped mass away from the tropical storm.  The removal of more mass caused the surface pressure to decrease.

Even though Tropical Storm Helene was strengthening, the distribution of wind speeds around Helene was still asymmetrical.  Winds to tropical storm force extended out 175 miles (280 km) in the eastern side of Tropical Storm Helene.  The winds in the western side of Helene’s circulation were blowing at less than tropical storm force.

Tropical Storm Helene will move through an environment favorable for intensification during the next 24 hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the western Gulf of Mexico and the northwestern Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Helene will intensify during the next 24 hours. Helene is likely to strengthen to a hurricane by Wednesday morning.  Helene could intensify rapidly after an inner core with an eye and an eyewall develops.

Tropical Storm Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Helene will be near the northeastern tip of the Yucatan Peninsula on Wednesday morning.  Helene will move over the eastern Gulf of Mexico on Wednesday.  Helene is likely to approach northern Florida on Thursday afternoon.

Tropical Storm Helene is likely to be a hurricane when it reaches the northeastern tip of the Yucatan Peninsula.  Helene will bring strong winds and heavy rain to the northeastern part of the Yucatan Peninsula and to western Cuba.

Tropical Storm Helene could be a major hurricane when it approaches northern Florida on Thursday.  Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.  Helene could also cause a storm surge of up to 15 feet (4.5 meters) along portions of the west coast of Florida.

A Storm Surge Warning is in effect for the portion of the coast from Indian Pass to Flamingo, Florida.  The Storm Surge Warning includes Tampa Bay and Charlotte Harbor.

Tropical Storm Helene Forms Over Northwest Caribbean Sea

Tropical Storm Helene formed over the Northwestern Caribbean Sea on Tuesday.  At 2:00 p.m. EDT on Tuesday the center of Tropical Storm Helene was located at latitude 19.4°N and longitude 84.5°W which put the center about 175 miles (280 km) south of the western tip of Cuba.  Helene 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 999 mb.

A Hurricane Watch is in effect for the portion of the coast from Indian Pass to Englewood, Florida.  The Hurricane Watch includes Tampa Bay.  A Hurricane Watch is in effect for the portion of the coast from Cabo Catoche to Tulum, Mexico.  The Hurricane Watch includes Cancun and Cozumel.  A Hurricane Watch is also in effect for the Cuban province of Pinar del Rio.

A Tropical Storm Warning is in effect for the Lower Florida Keys west of Seven Mile Bridge.  A Tropical Storm Warning is in effect for the Dry Tortugas.  A Tropical Storm Warning is in effect for the portion of the coast from Rio Lagartos to Tulum, Mexico.  The Tropical Storm Warning includes Cancun and Cozumel.  A Tropical Storm Warning was also in effect for the Cuban provinces of Artemisa, Pinar del Rio and Isle of Youth.

A Tropical Storm Watch is in effect for the Middle Florida Keys from Seven Mile Bridge to Channel 5 Bridge.  A Tropical Storm Watch is in effect for the portion of the coast from Englewood to Flamingo, Florida.  A Tropical Storm Watch is in effect for the portion of the coast from the Walton/Bay County Line to Indian Pass, Florida.

A U.S. Air Force Reserve Hurricane Hunter reconnaissance aircraft found that a low pressure system previously designated as Potential Tropical Cyclone Nine had strengthened over the Northwestern Caribbean Sea on Tuesday morning.  Based on data collected by the reconnaissance flight, the U.S. National Hurricane Center designated the system as Tropical Storm Helene.

The circulation around Tropical Storm Helene exhibited more organization on Tuesday.  The reconnaissance plane found a well defined low level center of circulation.  Even though the circulation around Helene was more organized, the distribution of thunderstorms was still asymmetrical.  Thunderstorms were occurring in bands in the eastern side of Tropical Storm Helene.  Bands in the western side of Helene consisted primarily of showers and lower clouds.  More thunderstorms were starting to develop in the bands in the western side of Helene’s circulation.  Storms near the center of Helene began to generate upper level divergence that pumped mass away from the tropical storm.

The distribution of wind speeds in Tropical Storm Helene was also asymmetrical.  Winds to tropical storm force extended out 140 miles (225 km) in the eastern side of Helene’s circulation.  The winds in the western side of Tropical Storm Helene were blowing at less than tropical storm force.

Tropical Storm Helene will move through an environment favorable for intensification during the next 24 hours.  Helene will move over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the western Gulf of Mexico and the northwestern Caribbean Sea.   The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Tropical Storm Helene will intensify during the next 24 hours.  Helene is likely to strengthen to a hurricane by Wednesday morning.

Tropical Storm Helene will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Helene toward the northwest during the next 24 hours.  On its anticipated track, Tropical Storm Helene will be near the northeastern tip of the Yucatan Peninsula on Wednesday morning.  Helene will move over the eastern Gulf of Mexico on Wednesday.  Helene is likely to approach northern Florida on Thursday afternoon.

Tropical Storm Helene is likely to be a hurricane when it reaches the northeastern tip of the Yucatan Peninsula.  Helene will bring strong winds and heavy rain to the northeastern part of the Yucatan Peninsula and to western Cuba.

Tropical Storm Helene could be a major hurricane when it approaches northern Florida on Thursday.  Helene will bring strong winds and heavy rain to northern Florida.  Heavy rain is likely to cause floods.  Helene could also cause a storm surge of up to 15 feet (4.5 meters) along portions of the coast of Florida.

A Storm Surge Watch is in effect for the portion of the coast from Indian Pass to Flamingo, Florida.  The Storm Surge Watch includes Tampa Bay and Charlotte Harbor.

Watches and Warnings Issued for Yucatan and Western Cuba

A risk posed by a low pressure system over the Northwestern Caribbean Sea prompted the issuance of Watches and Warnings for Yucatan and western Cuba on Monday morning.  The low pressure system was designated as Potential Tropical Cyclone Nine by the U.S. National Hurricane Center.  At 11:00 a.m. EDT on Monday the center of Potential Tropical Cyclone Nine was located at latitude 17.6°N and longitude 82.0°W which put the center about 350 miles (565 km) south-southeast of the western tip of Cuba.  Potential Tropical Cyclone Nine was moving toward the north at 6 m.p.h. (10 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 1004 mb.

A Hurricane Watch is in effect for the portion of the coast from Cabo Catoche to Tulum, Mexico.  The Hurricane Watch includes Cancun and Cozumel.  A Hurricane Watch is also in effect for the Cuban province of Pinar del Rio.

A Tropical Storm Warning is in effect for the portion of the coast from Rio Lagartos to Tulum, Mexico.  The Tropical Storm Warning includes Cancun and Cozumel.  A Tropical Storm Warning was also in effect for the Cuban provinces of Artemisa, Pinar del Rio and Isle of Youth.

The U.S. National Hurricane Center changed the designation of former Invest 97L to Potential Tropical Cyclone Nine on Monday morning.  The low pressure system still had a large asymmetrical circulation.  There were not many thunderstorms near the center of Potential Tropical Cyclone Nine.  Thunderstorms were occurring in bands developed in the eastern side of the low pressure system.  Bands in the western side of Potential Tropical Cyclone Nine consisted primarily of showers and lower clouds.

Potential Tropical Cyclone Nine will move through an environment favorable for the formation of a tropical cyclone during the next 24 hours.  The low pressure system will be over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the western Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Potential Tropical Cyclone Nine is likely to form into a tropical depression or a tropical storm during the next 24 hours.

A reconnaissance plane is on its way to investigate Potential Tropical Cyclone Nine.

Potential Tropical Cyclone Nine will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Potential Tropical Cyclone Nine toward the north-northwest during the next 24 hours.  On its anticipated track, Potential Tropical Cyclone Nine will move approach Yucatan and the western end of Cuba on Tuesday afternoon.  Potential Tropical Cyclone Nine is likely to move over the Gulf of Mexico on Wednesday.

Potential Tropical Cyclone Nine could be a hurricane when it reaches Yucatan and western Cuba.  It will bring strong winds and locally heavy rain.  Heavy rain could cause flash floods in some locations.

Potential Tropical Cyclone Nine is likely to affect Florida on Thursday.  It is likely to be a hurricane when it reaches Florida.