Tag Archives: Cape Fear

Low Pressure System Drops Heavy Rain on North Carolina

A low pressure system designated as Potential Tropical Cyclone Eight dropped heavy rain over parts of North Carolina on Monday.  At 2:00 p.m. EDT on Monday the center of Potential Tropical Cyclone Eight was located at latitude 33.1°N and longitude 78.3°W which put the center about 60 miles (95 km) south-southeast of Cape Fear, North Carolina.  The low pressure system was moving toward the north-northwest at 5 m.p.h. (8 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 1005 mb.

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

A low pressure system designated as Potential Tropical Cyclone Eight dropped heavy rain over the area near Cape Fear, North Carolina.  Even though the center of circulation was still over the Atlantic Ocean, converging wind flows in the northern side of the low pressure system generated a band of persistent heavy rain.  Heavy rain fell over eastern South Carolina, and central and eastern North Carolina.  Widespread flooding was reported in Carolina Beach.

Flash Flood Warnings were in effect for Columbus County, Brunswick County and Bladen County.

The low pressure system designated as Potential Tropical Cyclone Eight will move around the southwestern part of high pressure system over the western Atlantic Ocean.  The high pressure system will steer Potential Tropical Cyclone Eight toward the northwest during the next 24 hours.  On its anticipated track, the center of the low pressure system will move near the border between South Carolina and North Carolina.

The low pressure system designated as Potential Tropical Cyclone Eight will weaken steadily as it moves farther inland.  Even though the low pressure system will weaken, it will continue to drop heavy rain over parts of North Carolina.  Persistent heavy rain is likely to cause additional flooding.

Elsewhere, Tropical Depression Gordon continued to spin east of the Northern Leeward Islands.  At 11:00 a.m. EDT on Monday the center of Tropical Depression Gordon was located at latitude 19.1°N and longitude 48.1°W which put the center about 985 miles (1580 km) east of the Northern Leeward Islands.  Gordon was moving toward the west at 7 m.p.h. (11 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 1006 mb.

 

Center of Tropical Storm Debby Near Savannah

The center of Tropical Storm Debby was near Savannah, Georgia on Tuesday morning.  At 11:00 a.m. EDT on Tuesday the center of Tropical Storm Debby was located at latitude 31.9°N and longitude 81.0°W which put the center about 15 miles (25 km) south of Savannah, Georgia.  Debby was moving toward the east-northeast at 6 m.p.h. (10 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 999 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Altamaha Sound Georgia to Surf City, North Carolina.  The Tropical Storm Warning included Charleston, South Carolina.

A Tropical Storm Watch was in effect for the portion of the coast from Surf City to Beaufort Inlet, North Carolina.

Tropical Storm Debby continued to drop heavy rain over parts of South Carolina and eastern Georgia.  The airport at Charleston, South Carolina reported 8.11 inches (206 mm) of rain during the past 24 hours.  Valdosta, Georgia received 2.75 inches (70 mm) of rain.  Sarasota, Florida reported 11.06 inches (281 mm) of rain from Debby.  Gainesville, Florida received 6.80 inches (173 mm) of rain.  Jacksonville, Florida reported 4.70 inches (119 mm) of rain.  It is likely that higher rainfall totals occurred in some places where bands moved persistently over the same locations.

Southerly winds blowing around the eastern side of Tropical Storm Debby were pushing water toward the coast of South Carolina.  There were numerous reports of water in streets in Charleston, South Carolina.

Tropical Storm Debby weakened during the day it spent moving slowly across northern Florida and southeastern Georgia.  Drier air wrapped around the western and southern sides of Debby’s circulation.  Bands in the southwestern and southeastern quadrants of Tropical Storm Debby consisted primarily of showers and lower clouds.  Showers and thunderstorms were occurring in bands in the outer parts of the northeastern and northwestern quadrants of Tropical Storm Debby.  There were also showers and lower clouds near the center of Debby.

The distribution of wind speeds in Tropical Storm Debby was also asymmetrical.  Winds to tropical storm force extended out 205 miles (330 km) in the eastern side of Debby.  Those winds were occurring in bands in the outer parts of Debby’s circulation.  The winds in the parts of Debby’s circulation that were over land were blowing at less than tropical storm force.

Tropical Storm Debby will move into an environment favorable for intensification.  Debby will move over water where the Sea Surface Temperatures are near 29°C.  It will move under the middle of an upper level ridge over the southeastern U.S.  The upper level winds are weak near the center of the ridge and there will be little vertical wind shear.  The drier air in the southern part of Debby’s circulation will inhibit intensification.  Tropical Storm Debby is likely to intensify slowly during the next 24 hours.

Tropical Storm Debby will be in an area where the steering winds are weak during the next 24 hours.  Debby is likely to move slowly toward the east-northeast during the rest of Tuesday.  A high pressure system located east of Tropical Storm Debby is forecast to strengthen on Wednesday.  That high pressure system will steer Debby slowly toward the north on Wednesday.  On its anticipated track, the center of Tropical Storm Debby could approach the coast of South Carolina on Wednesday night.

Tropical Storm Debby will continue to drop heavy rain on parts of South Carolina, North Carolina and eastern Georgia.  Since Debby will move slowly, persistent heavy rain is likely to cause floods.

Flood Watches are in effect for parts of South Carolina, North Carolina and eastern Georgia.

Southerly winds blowing around the eastern side of Tropical Storm Debby will continue to push water toward the coast of South Carolina and North Carolina.  Debby could cause a storm surge of up to 6 feet (1.8 meters).

A Storm Surge Warning is in effect for the portion of the coast from Altamaha Sound, Georgia, to South Santee River, South Carolina.

A Storm Surge Watch is in effect for the portion of the coast from South Santee River, South Carolina to Cape Fear, North Carolina.

Tropical Storm Ophelia Brings Wind and Rain to Eastern North Carolina, Virginia

Tropical Storm Ophelia brought wind and rain to eastern North Carolina and Virginia on Saturday morning. At 8:00 a.m. EDT on Saturday the center of Tropical Storm Ophelia was located at latitude 35.1°N and longitude 77.0°W which put it about 40 miles (65 km) northwest of Cape Lookout, North Carolina. Ophelia was moving toward the north at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h). The minimum surface pressure was 983 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear, North Carolina to Fenwick Island, Delaware. The Tropical Storm Warning included Albemarle Sound and Pamlico Sound. A Tropical Storm Warning was also in effect for Chesapeake Bay south of North Beach. A Tropical Storm Warning was in effect for the Tidal Potomac south of Cobb Island.

Tropical Storm Ophelia brought wind and rain as it moved inland over eastern North Carolina on Saturday morning. The circulation around Ophelia was large. Tropical Storm Opehila was interacting with a high pressure system over eastern Canada to produce strong winds northeast of the center of circulation. Winds to tropical storm force extended out 310 miles (500 km) in the northeastern quadrant of Ophelia’s circulation. Winds to tropical storm force extended out 140 miles (225 km) in the other parts of Tropical Storm Ophelia.

A weather station in Cape Lookout, North Carolina reported a sustained wind speed of 47 m.p.h. (75 km/h) and a wind gust of 71 m.p.h. (115 km/h). A weather station in Morehead City, North Carolina reported a sustained wind speed of 43 m.p.h. (68 km/h) and a wind gust of 53 m.p.h. (85 km/h). NOAA buoy 41037 near Wrightsville Beach reported a sustained wind speed of 54 m.p.h. (87 km/h) and a wind gust of 83 m.p.h. (134 km/h).

Tropical Storm Ophelia will move around the western side of a high pressure system over the western Atlantic Ocean. The high pressure system will steer Ophelia toward the north during the next 24 hours. On its anticipated track, Tropical Storm Ophelia will move inland over eastern North Carolina and Virginia. Ophelia will bring strong, gusty winds and locally heavy rain to eastern North Carolina, eastern Virginia, southeastern Maryland and southern Delaware.

The heaviest rain was falling in bands in the northern and western parts of Tropical Storm Ophelia. Bands in the eastern and southern parts of Ophelia’s circulation consisted primarily of showers and lower clouds. Locally heavy rain could cause flash floods in some locations. Flood Watches were in effect for eastern North Carolina, eastern Virginia, Maryland and Delaware.

Easterly winds in the northern side of Tropical Storm Ophelia will blow water toward the coast. A storm surge of up to 6 feet (1.8 meters) could occur in some locations. A Storm Surge Warning was in effect for the portion of the coast from Bogue Inlet, North Carolina to Chincoteague, Virginia. The Storm Surge Warning included Albemarle Sound, Pamlico Sound, the Pamlico River and the Neuse River. A Storm Surge Warning was in effect for Chesapeake Bay south of Colonial Beach, Virginia. Large waves will also cause significant beach erosion.

Tropical Storm Ophelia Develops South of Cape Hatteras

Tropical Storm Ophelia developed south of Cape Hatteras on Friday afternoon. At 2:00 p.m. EDT on Friday the center of Tropical Storm Ophelia was located at latitude 32.7°N and longitude 76.0°W which put it about 185 miles (295 km) south of Cape Hatteras, North Carolina. Ophelia was moving toward the north-northwest at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h). The minimum surface pressure was 992 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear, North Carolina to Fenwick Island, Delaware. The Tropical Storm Warning included Albemarle Sound and Pamlico Sound. A Tropical Storm Warning was also in effect for Chesapeake Bay south of North Beach. A Tropical Storm Warning was in effect for the Tidal Potomac south of Cobb Island.

The U.S. National Hurricane Center designated a low pressure system south of Cape Hatteras as Tropical Storm Ophelia on Friday afternoon. Drier air was wrapping around the southern and eastern sides of Ophelia’s circulation. The drier air was making the distribution of thunderstorms asymmetrical. Thunderstorms were occurring in bands in the northern and western parts of Tropical Storm Ophelia. Bands in the southern and eastern parts of Ophelia consisted primarily of showers and lower clouds. Storms north and west of the center of Ophelia’s circulation generated upper level divergence that pumped mass away from the tropical storm. The circulation around Tropical Storm Ophelia was large, Winds to tropical storm force extended out 275 miles (445 km) from the center of circulation.

Tropical Storm Ophelia will move through an environment somewhat favorable for intensification during the next 12 hours. Ophelia will move over the Gulf Stream where the Sea Surface Temperatures are near 30°C. It will move under the eastern side of an upper level trough over the eastern U.S. The upper level trough will produce southwesterly winds that will blow toward the top of Ophelia’s circulation. Those winds will cause moderate vertical wind shear. However, the flow of air in the upper levels will also provide divergence aloft that will pump mass away from the tropical storm. The removal of mass will cause the surface pressure to decrease. The drier air in the southern and eastern parts of Tropical Storm Ophelia will inhibit the formation of thunderstorms in those regions. Tropical Storm Ophelia could intensify during the next 12 hours, while it is over the Gulf Stream.

Tropical Storm Ophelia will move around the western side of a high pressure system over the western Atlantic Ocean. The high pressure system will steer Ophelia toward the north-northwest during the next 24 hours. On its anticipated track, Tropical Storm Ophelia will approach the coast of North Carolina on Friday night. Ophelia will bring strong, gusty winds and locally heavy rain to eastern North Carolina, eastern Virginia, southeastern Maryland and southern Delaware. NOAA buoy 41025 at Diamond Shoals, North Carolina reported a sustained wind speed of 47 m.p.h. (76 km/h) and a wind gust of 60 m.p.h. (97 km/h). A NOAA C-MAN station at Cape Lookout, North Carolina reported a sustained wind speed of 45 m.p.h. (72 km/h) and a wind gust of 53 m.p.h. (83 km/h)

Locally heavy rain could cause flash floods in some locations. Flood Watches were in effect for eastern North Carolina, eastern Virginia, Maryland and Delaware.

Easterly winds in the northern side of Tropical Storm Ophelia will blow water toward the coast. A storm surge of up to 6 feet (1.8 meters) could occur in some locations. A Storm Surge Warning was in effect for the portion of the coast from Beaufort Inlet, North Carolina to Chincoteague, Virginia. The Storm Surge Warning included Albemarle Sound, Pamlico Sound, the Pamlico River and the Neuse River. A Storm Surge Warning was in effect for Chesapeake Bay south of Colonial Beach, Virginia. Large waves will also cause significant beach erosion.

Low Pressure System Prompts Tropical Storm Warnings for Mid-Atlantic Coast

A low pressure system formed over the Atlantic Ocean off the coast of the southeast U.S. on Thursday morning. The U.S. National Hurricane Center designated the low pressure system as Potential Tropical Cyclone Sixteen and issued Tropical Storm Warnings for portions of the Mid-Atlantic coast. At 2:00 p.m. EDT on Thursday the center of Potential Tropical Cyclone Sixteen was located at latitude 29.0°N and longitude 75.9°W which put it about 430 miles (690 km) south of Cape Hatteras, North Carolina. Potential Tropical Cyclone Sixteen was moving toward the north at 9 m.p.h. (15 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 1012 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear, North Carolina to Fenwick Island, Delaware. The Tropical Storm Warning included Albemarle Sound and Pamlico Sound. A Tropical Storm Warning was also in effect for Chesapeake Bay south of Smith Point.

A low pressure system formed over the Atlantic Ocean off the coast of the southeast U.S. on Thursday morning. The low pressure system formed as an extratropical cyclone. There was a large counterclockwise circulation around the low pressure system. There was not a well formed, distinct low level center of the circulation. Thunderstorms were occurring in a band that wrapped around the eastern and northern side of the low pressure systems. Fragmented bands in other parts of the circulation consisted primarily of showers and lower clouds.

Potential Tropical Cyclone Sixteen will move through an environment favorable for intensification of an extratropical cyclone during the next 24 hours. The low pressure system will move over water where the Sea Surface Temperatures are near 28°C. It will move under the eastern side of an upper level trough over the eastern U.S. The upper level trough will produce southwesterly winds that will blow across the top of Potential Tropical Cyclone Sixteen. Those winds will cause moderate vertical wind shear. However, the flow of air in the upper levels will also provide divergence aloft that will pump mass away from the surface low pressure system. The removal of mass will cause the surface pressure to decrease. Potential Tropical Cyclone Sixteen is likely to intensify during the next 24 hours. The low pressure system could make a transition to a tropical storm later on Friday when it moves over the warmer water in the Gulf Stream.

The upper level trough over the eastern U.S. will steer Potential Tropical Cyclone Sixteen toward the north during the next 24 hours. On its anticipated track Potential Tropical Cyclone will approach the coast of North Carolina on Friday night. The low pressure system will bring gusty winds and locally heavy rain to eastern North Carolina, eastern Virginia, southeastern Maryland and southern Delaware. The gusty winds will blow water toward the coast. A storm surge of up to 5 feet (1.5 meters) could occur in some locations. Large waves will cause significant beach erosion. Locally heavy rain could cause flash floods in some locations.

Elsewhere over the Atlantic Ocean, Hurricane Nigel was speeding toward the northeast as it passed southeast of Newfoundland. At 11:00 a.m. EDT on Thursday the center of Hurricane Nigel was located at latitude 42.2°N and longitude 45.0°W which put it about 505 miles (815 km) southeast of Cape Race,, Newfoundland. Nigel was moving toward the northeast at 30 m.p.h. (48 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 977 mb.

Hurricane Ian Makes Landfall in South Carolina

Hurricane Ian made landfall in South Carolina on Friday afternoon. According to the National Hurricane Center the center of Hurricane Ian officially made landfall near Georgetown, South Carolina at 2:05 p.m. EDT on Friday. At 2:05 p.m. EDT on Friday the center of Hurricane Ian was located at latitude 33.3°N and longitude 79.2°W which put it about 55 miles (90 km) east-southeast of Charleston, South Carolina. Ian was moving toward the north at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 977 mb.

A Hurricane Warning was in effect for the portion of the coast from Savannah River, Georgia to Cape Fear, North Carolina. The Hurricane Warning included Charleston, South Carolina. A Hurricane Watch was in effect for the portion of the coast from Cape Fear to Surf City, North Carolina. A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear to Duck, North Carolina. The Tropical Storm Warning included Pamlico Sound. A Tropical Storm Warning is also in effect for the portion of the coast from Altamaha Sound to Savannah River, Georgia.

The center of Hurricane Ian moved over the coast of South Carolina near Georgetown at 2:05 p.m. EDT on Friday. Ian was a Category 1 hurricane at the time of landfall. Winds to hurricane force extended out70 miles (110 km) from the center of Ian’s circulation. Winds to tropical storm force extended out 275 miles (445 km) from the center of circulation. The Hurricane Intensity Index (HII) was 12.7. The Hurricane Size Index (HSI) was 12.7 and the Hurricane Wind Intensity Size Index (HWISI) was 30.9. Hurricane Ian was capable of causing regional minor damage.

Hurricane Ian was bringing strong gusty winds to the coastal areas of South Carolina on Friday afternoon. The weather station at the Charleston airport (KCHS) reported a sustained wind speed of 50 m.p.h. (80 km/h) and a wind gust of 68 m.p.h. (101 m.p.h.). Heavy rain was also falling over Charleston and there were reports of flooded streets. Hurricane Ian was causing a storm surge east of Georgetown where the winds were blowing water toward the coast. A surge of 4 to 7 feet (1.2 to 2.1 meters) was possible in the part of the coast between Georgetown and Cape Fear, North Carolina. A Storm Surge Warning is in effect for the portion of the coast from the Savannah River, Georgia to Cape Fear, North Carolina. Winds and waves were causing erosion along the coast.

Hurricane Ian will weaken gradually as it moves inland over eastern South Carolina. The center of Ian will move over south central South Carolina during Friday night. Ian will produce strong gusty winds over South Carolina and eastern and central North Carolina. Gusts to tropical storm force could affect the area around Charlotte, North Carolina. Minor wind damage and widespread electricity outages could occur in those areas. Gusty winds could push over trees in locations where the ground is saturated. Heavy rain was already falling over South Carolina, eastern North Carolina,, and southeastern Virginia. Flood Watches were in effect for much of South Carolina, North Carolina and southeastern Virginia. Southerly winds will push water toward the coast in places east of Georgetown, South Carolina. The storm surge is likely to continue in those places for a few more hours.

Hurricane Ian Approaches South Carolina

Hurricane Ian approached the coast of South Carolina on Friday morning. At 8:00 p.m. EDT on Friday the center of Hurricane Ian was located at latitude 31.4°N and longitude 79.1°W which put it about 105 miles (165 km) south-southeast of Charleston South Carolina. Ian was moving toward the north at 9 m.p.h. (15 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 984 mb.

A Hurricane Warning was in effect for the portion of the coast from Savannah River, Georgia to Cape Fear, North Carolina. The Hurricane Warning included Charleston, South Carolina. A Hurricane Watch was in effect for the portion of the coast from Cape Fear to Surf City, North Carolina. A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear to Duck, North Carolina. The Tropical Storm Warning included Pamlico Sound. A Tropical Storm Warning is also in effect for the portion of the coast from Altamaha Sound to Savannah River, Georgia.

Hurricane Ian did not have the typical structure of a tropical hurricane on Friday morning. Ian was in the middle of a transition to an extratropical cyclone. The circulation around Hurricane Ian was also interacting with a stationary front near the coast of the Carolinas. The result of these factors was that the strongest winds were occurring in the western side of Ian’s circulation. Winds to hurricane force extended out 70 miles (110 km) in the western side of Hurricane Ian. Winds to tropical storm force extended out 480 miles (775 km) in the northeaster quadrant of Ian. Tropical storm force winds extended out 185 miles (300 km) in the other parts of Ian’s circulation. The interaction with the stationary front was also causing the heaviest rain to fall in the northern half of Hurricane Ian.

The Hurricane Intensity Index (HII) for Hurricane Ian is 12.7. The Hurricane Size Index (HSI) is 20.6 and the Hurricane Wind Intensity Size Index (HWISI) is 33.3. Hurricane Ian is capable of causing widespread minor damage.

Hurricane Ian will move through an environment marginally favorable for intensification during the next few hours. Ian will move over water where the Sea Surface Temperatures are near 28˚C. An upper level trough over the eastern U.S. will produce southerly winds that will blow toward the top of Ian’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification. Hurricane Ian could get a little stronger before it makes landfall in South Carolina. The vertical wind shear will cause Hurricane Ian to continue its transformation to an extratropical cyclone.

The upper level trough will steer Hurricane Ian toward the north during the next 24 hours. On its anticipated track the center Hurricane Ian could make landfall in South Carolina between Charleston and Myrtle Beach on Friday afternoon. Ian will be a Category 1 hurricane on the Saffir-Simpson Scale when it reaches South Carolina. Ian will bring strong gusty winds and locally heavy rain. If Ian makes landfall east of Charleston, the the strongest winds will affect that city. Widespread minor wind damage and electricity outages could occur. Air revolving around the northern side of Ian’s circulation will interact with the stationary front near the coast to enhance the rising motion in that region. The enhanced rising motion could produce heavy rainfall near the stationary front. Heavy rain could cause flash floods in some locations. Flood Watches are in effect for parts of South Carolina and North Carolina. Southeasterly winds blowing around the northeastern side of Hurricane Ian will blow water toward the coast. A storm surge of 4 to 7 feet (1.2 to 2.0 meters) could occur. A Storm Surge Warning is in effect for the portion of the coast from the Savannah River, Georgia to Cape Fear, North Carolina. Serious coastal erosion is likely.

Ian Strengthens Back to a Hurricane

One time major hurricane and former Tropical Storm Ian strengthened back to a hurricane over the Atlantic Ocean east of Florida on Thursday afternoon. At 5:00 p.m. EDT on Thursday the center of Hurricane Ian was located at latitude 29.3°N and longitude 79.9°W which put it about 240 miles (390 km) south of Charleston South Carolina. Ian was moving toward the north-northeast at 10 m.p.h. (16 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 986 mb.

A Hurricane Warning was in effect for the portion of the coast from Savannah River, Georgia to Cape Fear, North Carolina. The Hurricane Warning included Charleston, South Carolina. A Hurricane Watch was in effect for the portion of the coast from Cape Fear to Surf City, North Carolina. A Hurricane Watch was also in effect for the portion of the coast from the Flagler/Volusia County Line, Florida to Savannah River, Georgia. A Tropical Storm Warning was in effect for the portion of the coast from Cape Fear to Duck, North Carolina. The Tropical Storm Warning included Pamlico Sound. A Tropical Storm Warning is also in effect for the portion of the coast from Vero Beach, Florida to Savannah River, Georgia.

The structure of Hurricane Ian contains elements of a hurricane and elements of an extratropical cyclone. Ian has a warm core in the middle and upper troposphere, which makes it a hurricane. However, cooler, drier air wrapped around the southern side of Ian and a cold front is forming east of Ian. The developing cold front is an element of an extratropical cyclone. Many of the thunderstorms in Hurricane Ian are occurring in bands in the northern and western parts of Ian’s circulation.

The wind field around Hurricane Ian also changed when Ian started a transition to an extratropical cyclones. The circulation around Ian is interacting with a large high pressure system centered over the Great Lakes. The interaction of Ian’s circulation with the high pressure system is causing the strongest winds to be in the northwestern quadrant of Hurricane Ian. Winds to hurricane force extend out 45 miles (75 km) in the northwestern quadrant of Ian. The size of the circulation around Hurricane Ian also increased when it started the transition to an extratropical cyclone. Winds to tropical storm force extend out 400 miles (645 km) in the eastern side of Ian. Winds to tropical storm force extend out 230 miles (370 km) in the western side.

Hurricane Ian will move through an environment somewhat favorable for intensification during the next 24 hours. Ian will move over water where the Sea Surface Temperatures are near 29˚C. An upper level trough over the eastern U.S. will produce southwesterly winds that will blow toward the top of Ian’s circulation. Those winds will cause moderate vertical wind shear. The wind shear will inhibit intensification. Hurricane Ian could intensify, if the center moves over the warm water in the Gulf Stream current. More thunderstorms could form near the center of Ian’s circulation and could look more like a hurricane for a few hours. The vertical wind shear will eventually cause Hurricane Ian to gradually continue its transformation to an extratropical cyclone.

The upper level trough will steer Hurricane Ian toward the north-northeast during the next 24 hours. On its anticipated track the center Hurricane Ian could make landfall in South Carolina on Friday afternoon. Ian is likely to be a Category 1 hurricane on the Saffir-Simpson Scale when it reaches South Carolina. Ian will bring strong gusty winds and locally heavy rain. Widespread minor wind damage and electricity outages could occur. Air revolving around the northern side of Ian’s circulation will interact with a stationary front near the coast to enhance the rising motion in that region. The enhanced rising motion could produce very heavy rainfall near the stationary front. Heavy rain could cause flash floods in some locations. Flood Watches are in effect for parts of South Carolina and North Carolina. Southeasterly winds blowing around the northeastern side of Hurricane Ian will blow water toward the coast. A storm surge of 4 to 7 feet (1.2 to 2.0 meters) could occur. A Storm Surge Warning is in effect for the portion of the coast from the Flagler/Volusia County Line, Florida to Cape Fear, North Carolina.

Hurricane Florence Causes Watches for Carolinas, Isaac for the Lesser Antilles

The potential impacts of Hurricane Florence caused Hurricane Watches to be issued for the Carolinas on Tuesday morning while the approach of Tropical Storm Isaac also caused Watches to be issued for some of the Lesser Antilles.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Florence was located at latitude 26.7°N and longitude 65.3°W which put it about 905 miles (1455 km) east-southeast of Cape Fear, North Carolina.  Florence was moving toward the west-northwest at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 950 mb.  A Hurricane Watch was in effect for the portion of the coast from Edisto Beach, South Carolina to the North Carolina-Virginia border including Pamlico and Albemarle Sounds.

Hurricane Florence was nearing the end of an eyewall replacement cycle on Tuesday morning.  A thin ring of showers and thunderstorms around the center of circulation was all that was left of the original eyewall.  A larger ring of thunderstorms surrounded an eye with a diameter of 36 miles (58 km).  Several other bands of showers and thunderstorms surround the new, larger eyewall.  Storms near the core of Hurricane Florence generated strong upper level divergence which pumped mass away from the hurricane.

The eyewall replacement cycle temporarily weakened Hurricane Florence, but it also made the circulation larger.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Florence was 25.1.  The Hurricane Size Index (HSI) was 15.3 and the Hurricane Wind Intensity Size Index (HWISI) was 40.4.

Hurricane Florence will be moving through an environment favorable for strong hurricanes.  Florence 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 Florence is likely to strengthen during the next 24 hours, but additional eyewall replacement cycles could cause the intensity to fluctuate.

Hurricane Florence will move around the western end of the subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence in a general west-northwesterly direction.  On its anticipated track the center of Hurricane Florence could approach the coast of North Carolina and South Carolina on Thursday.  It will very likely be a major hurricane at that time.

Tropical Storm Isaac moved steadily toward the Lesser Antilles and Watches were issued for some of those islands.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Isaac was located at latitude 14.6°N and longitude 49.7°W which put it about 775 miles (1250 km) east of the Lesser Antilles.  Isaac was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 996 mb.  Hurricane Watches were in effect for Guadeloupe, Martinique and Dominica.  Tropical Storm Watches were in effect for Antigua and Montserrat.

Elsewhere over the tropical Atlantic Ocean, Hurricane Helene moved far south of the Azores.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Helene was located at latitude 16.5°N and longitude 34.3°W which put it about 1550 miles (2495 km) south-southwest of the Azores.  Helene was moving toward the northwest at 12 m.p.h. (19 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 966 mb.

Florence Strengthens Into a Major Hurricane

Hurricane Florence strengthened into a Major Hurricane on Monday.  At 11:00 p.m. EDT on Monday the center of Hurricane Florence was located at latitude 25.9°N and longitude 62.4°W which put it about 1085 miles (1745 km) east-southeast of Cape Fear, North Carolina.  Florence was moving toward the west-northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 944 mb.

Hurricane Florence intensified rapidly on Monday morning and early afternoon.  An eye with a diameter of 18 miles (29 km) formed at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Florence.  Storms near the core were generating strong upper level divergence which pumped mass away from the hurricane.

Hurricane Florence increased in size on Monday.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 150 miles (240 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Florence was 28.2.  The Hurricane Size Index (HSI) was 14.0 and the Hurricane Wind Intensity Size Index (HWISI) was 42.2.  Hurricane Florence was capable of causing extensive significant damage.

Microwave satellite imagery indicated that an inner rainband may have wrapped around the original eye and eyewall.  An eyewall replacement cycle may have begun and that may have halted the rapid intensification of Hurricane Florence.  Florence could weaken during the next few hours while the inner eyewall weakens.  Hurricane Florence will move through an area capable of supporting strong hurricanes on Tuesday and Wednesday.  Florence will move over water where the Sea Surface Temperature is near 29°C.  It will move through an area where the upper level winds are weak and there will be little vertical wind shear.  If the inner eyewall dissipates during the next day or so, then Hurricane Florence could strengthen again.

Hurricane Florence will move around the western end of the subtropical high pressure system during the next several days.  The high will steer Florence toward the west-northwest.  On its anticipated track Hurricane Florence will approach the coast of North Carolina on Thursday afternoon.  The winds steering Florence could weaken as it approaches the coast and the track forecast becomes much more uncertain at that time.

Elsewhere, Hurricane Helene and Tropical Storm Isaac were spinning over the tropical Atlantic Ocean.  At 11:00 p.m. EDT on Monday the center of Hurricane Helene was located at latitude 15.5°N and longitude 32.4°W which put it about 1590 miles (2555 km) south of the Azores.  Helen was moving toward the west-northwest at 12 m.p.h. (19 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 968 mb.

At 11:00 p.m. EDT on Monday the center of Tropical Storm Isaac was located at latitude 14.5°N and longitude 46.9°W which put it about 960 miles (1550 km) east of the Lesser Antilles.  Isaac was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 997 mb.