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Tropical Storm Fay Forms East of Cape Hatteras

Tropical Storm Fay formed east of Cape Hatteras on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Fay was located at latitude 35.5°N and longitude 74.9°W which put it about 40 miles (65 km) east-northeast of Cape Hatteras, North Carolina.  Fay was moving toward the north at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1005 mb.

A Tropical Storm Warning was issued for the portion of the coast from Cape May, New Jersey to Watch Hill, Rhode Island including Long Island and Long Island Sound.

A new center of circulation formed near the northern end of a band of showers and thunderstorms which was on the eastern side of a larger low pressure system that was previously designated as Invest 98L.  A reconnaissance aircraft detected winds to tropical storm force and the National Hurricane Center designated the system as Tropical Storm Fay.  Fay is the sixth named Atlantic tropical storm of 2020 and it formed earlier than any other sixth Atlantic tropical storm in the satellite era.

The circulation around Tropical Storm Fay was asymmetrical.  The strongest winds were occurring a band of showers and thunderstorms on the eastern side of Fay.  The inner end of the band was wrapping around the northern side of the center of circulation.  Bands on the western side of the tropical storm consisted primarily of showers and lower clouds.  Storms near the center began to generate upper level divergence which was pumping mass away to the north and east of the tropical storm.  Winds to tropical storm force extended out about 140 miles (225 km) in the eastern half of Tropical Storm Fay.  The winds in the western half of Fay were blowing at less than tropical storm force.

Tropical Storm Fay will move through an environment somewhat favorable for intensification during the next 18 to 24 hours.  Fay will move over water where the Sea Surface Temperature is near 26°C.  An upper level trough over the eastern U.S. will produce southwesterly winds which will blow toward the top of the tropical storm.  Those winds will impede upper level divergence to the west of Tropical Storm Fay and they will cause moderate vertical wind shear.  The wind shear will inhibit intensification, but it will not likely to be strong enough to prevent Fay from strengthening.  Tropical Storm Fay could intensify during the next 12 to 18 hours.

The upper level trough and a high pressure system over the Atlantic Ocean will interact to steer Tropical Storm Fay toward the north during the next day or two.  On its anticipated track the center of Tropical Storm Fay could approach southern New Jersey on Friday afternoon.  Fay could move across Long Island on Friday night.

Since the strongest rainband and winds are on the eastern side of Tropical Storm Fay, the portion of the coast south of New Jersey may not experience tropical storm force winds.  Gusty winds are likely along the coast of New Jersey, Long Island, southeastern New York, Connecticut and Rhode Island.  Heavy rain could also fall in those locations.  Easterly winds blowing around the northern side of Tropical Storm Fay will push water toward the coast.  The water level could rise several feet (one meter) at some locations.  Waves could also cause some beach erosion.

Tropical Storm Dorian Strengthens, Hurricane Warnings for Virgin Islands

Tropical Storm Dorian strengthened on Wednesday morning and it was on the verge of becoming a hurricane.  Hurricane Warnings were issued for Vieques, Culebra, the U.S. Virgin Islands and the British Virgin Islands. At 11:00 a.m. EDT on Wednesday the center of Tropical Storm Dorian was located at latitude 17.5°N and longitude 64.5°W which put it about 25 miles (40 km) south of St. Croix.  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 999 mb.

Hurricane Warnings were in effect for Vieques, Culebra, the U.S. Virgin Islands, and the British Virgin Islands.  A Tropical Storm Warning and a Hurricane Watch was in effect for Puerto Rico.  A Tropical Storm Watch was in effect for the portion of the coast of the Dominican Republic from Isla Saona to Samana.

The circulation around Tropical Storm Dorian exhibited much greater organization on Wednesday morning.  A ring of strong thunderstorms wrapped almost completely around the center of circulation.  The strongest winds were occurring in the northeastern part of that ring of storms.  Bands of showers and thunderstorms were revolving around the core of Dorian.  Storms near near the core were generating upper level divergence which was pumping mass away to the north and northeast of the tropical storm.  The circulation also increased in size on Wednesday morning.  Winds to tropical storm force extended out about 70 miles (110 km) from the center of circulation.

Tropical Storm Dorian will move through an environment favorable for intensification during the next few days.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  It will move northeast of an upper level low during the next 24 hours.  The low will produce some southerly winds which will blow toward the top of the circulation, but the winds will not be strong enough to prevent intensification.  The wind shear will decrease on Friday and Dorian could strengthen into a major hurricane near the Bahamas.

The upper level low will help to steer Tropical Storm Dorian toward the northwest during the next 24 to 36 hours.  A ridge of high pressure will build north of Dorian on Friday.  The ridge will block Dorian from moving north and it will steer Dorian toward the west-northwest.  On its anticipated track Tropical Storm Dorian will pass over the Virgin Islands near the eastern end of Puerto Rico today.  Dorian will be near the northern Bahamas on Saturday and it could approach the east coast of Florida by Sunday night.  Dorian could be a major hurricane when it approaches the east coast of the U.S.

Elsewhere over the Atlantic Ocean, former Tropical Storm Erin weakened to a tropical depression.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Erin was located at latitude 33.6°N and longitude 72.8°W which put it about 190 miles (305 km) southeast of Cape Hatteras, North Carolina.  Erin was moving toward the northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

Tropical Storm Dorian Moves Toward Puerto Rico

Tropical Storm Dorian moved toward Puerto Rico on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Dorian was located at latitude 16.0°N and longitude 63.0°W which put it about 275 miles (440 km) east-southeast of Ponce, Puerto Rico.  Dorian was moving toward the northwest at 13 m.p.h. (20 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 1006 mb.

A Hurricane Watch was issued for Puerto Rico.  Tropical Storm Warnings were in effect for Puerto Rico, Culebra, Vieques, the U.S. Virgin Islands and the British Virgin Islands.  A Tropical Storm Watch was issued for the coast of the Dominican Republic from Isla Saona to Puerto Plata.

The original low level center of Tropical Storm Dorian passed south of Barbados and St. Lucia on Tuesday morning.  Dorian dropped heavy rain and there were reports of flash floods on Martinique.  The original center weakened on Tuesday afternoon and a new low level center formed about 60 miles farther to the north.  The formation of a new center of circulation caused the forecast future track of Tropical Storm Dorian to be shifted northward as well.

Even with the formation of a new center of circulation, the overall circulation around Tropical Storm Dorian did not change much on Tuesday.  The circulation around Dorian remained small.  Winds to tropical storm force only extended out about 45 miles (75 km) from the center of circulation.  A broken ring of thunderstorms surrounded the new low level center.  Bands of showers and thunderstorms were revolving the center of Tropical Storm Dorian.  Storms near the center were producing upper level divergence which was pumping mass away to the north of the tropical storm.

Tropical Storm Dorian will move through an environment somewhat favorable for intensification on Wednesday.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  An upper level low northwest of Puerto Rico will produce southerly winds which will blow toward the top of the circulation.  Those winds will cause some vertical wind shear, which will inhibit intensification.  A large mass of drier air is north of Tropical Storm Dorian and the drier air could also inhibit intensification if it gets pulled into the circulation around Dorian.  The small size of the circulation around Tropical Storm Dorian means that it could weaken or strengthen quickly if the environmental conditions change significantly.  Dorian is likely to weaken when it crosses Puerto Rico on Wednesday night.

The upper low northwest of Puerto Rico will help to steer Tropical Storm Dorian toward the northwest on Wednesday.  On its anticipated track Tropical Storm Dorian could reach Puerto Rico by Wednesday evening.  Dorian will bring gusty winds and it will drop locally heavy rain on Puerto Rico.  Locally heavy rain could cause flash floods in some locations.  A high pressure system will build north of Tropical Storm Dorian on Thursday and Friday.  The high will turn Dorian back toward the west-northwest.  Dorian could approach the east coast of Florida on Sunday.

Elsewhere over the Atlantic Ocean, Tropical Depression Six strengthened into Tropical Storm Erin southeast of Cape Hatteras on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Erin was located at latitude 31.9°N and longitude 72.1°W which put it about 300 miles (485 km) southeast of Cape Hatteras, North Carolina.  Erin was moving toward the west at 2 m.p.h. (3 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. (65 km/h).  The minimum surface pressure was 1005 mb.  Tropical Storm Erin is forecast to move northeast toward Nova Scotia.

Tropical Storm Dorian Brings Wind and Rain to Barbados

Tropical Storm Dorian brought wind and rain to Barbados on Monday night.  Observations made by a U.S. Air Force Reserve Hurricane Hunter aircraft indicated that the center of Tropical Storm Dorian passed just south of Barbados on Monday night.  Dorian brought winds to tropical storm force and locally heavy rain.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Dorian was located at latitude 13.2°N and longitude 59.7°W which put it about 95 miles (155 km) east-southeast of St. Lucia.  Dorian was moving toward the west-northwest at 13 m.p.h. (20 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 1003 mb.

Tropical Storm Warnings were in effect for Barbados, St. Lucia, Martinique, St. Vincent and the Grenadines. Tropical Storm Watches have been issued for Puerto Rico, Grenada, Dominica, Saba and St. Eustatius.

The circulation around Tropical Storm Dorian remained fairly small on Monday.  Winds to tropical storm force only extended out about 45 miles (75 km) from the center of circulation.  Thunderstorms were occurring primarily in bands in the northern half of the circulation.  Bands in the southern half of the circulation consisted primarily of showers and lower clouds.  Storms near the center of Dorian were generating upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Dorian will move through an environment somewhat favorable for intensification.  Dorian will move over water where the Sea Surface Temperature is near 29°C.  Tropical Storm Dorian will move south of an upper level ridge.  The ridge will produce easterly winds which will cause some vertical wind shear, but the shear should not be strong enough to prevent intensification.  Dorian will move just south of a large mass of drier air.  It appears that some drier air will get pulled into circulation at times and the drier air will interrupt periods of intensification.  Since the circulation around Tropical Storm Dorian is very small, Dorian could strengthen or weaken very quickly if environmental conditions change.

Tropical Storm Dorian will move south of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Dorian toward the west-northwest during the next several days.  On its anticipated track the center of Tropical Storm Dorian will pass near St. Lucia on Tuesday morning.  Dorian could approach Puerto Rico on Wednesday.

Elsewhere over the Atlantic Ocean, Tropical Depression Six formed off the southeast coast of the U.S.  At 11:00 p.m. EDT on Monday the center of Tropical Depression Six was located at latitude 31.5N and longitude 72.2W which put it about 320 miles southeast of Cape Hatteras, North Carolina. It was moving toward the east at 3 m.p.h. The maximum sustained wind speed was 35 m.p.h. and the minimum surface pressure was 1010 mb.

Florence Still Producing Heavy Rain and Floods in Carolinas

Although former Hurricane Florence weakened to a tropical depression on Sunday, it was still producing heavy rain and causing floods in portions of the Carolinas.  At 5:00 p.m. EDT on Sunday the center of Tropical Depression Florence was located at latitude 34.6°N and longitude 82.2°W which put it about 25 miles (40 km) south-southeast of Greenville, South Carolina.  Florence was moving toward the north at 14 m.p.h. (22 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.

Slow movement of Tropical Depression Florence resulted in persistent heavy rain over portions of North Carolina and South Carolina.  The National Weather Service Office in Newport/Morehead City, North Carolina measured 25.20 inches (64.0 cm) of rain with Florence.  The airport in Wilmington, North Carolina measured 23.59 inches (59.9 cm) of rain.  A Remotely operated Automated Weather Station (RAWS) in Marion, South Carolina measured 18.13 inches (46.0 cm) of rain.  There were reports of up to ten inches (25.4 cm) at some locations around Charlotte, North Carolina.  Runoff of the persistent heavy rain has caused floods in many locations.  The Cape Fear River near Chinquapin, North Carolina has risen above the previous record flood level.  Parts of the Cape Fear River, Neuse River, Trent River and Lumber River are at major flood levels.  Minor and moderate flooding is occurring in numerous other places around North Carolina and South Carolina.

Tropical Depression Florence has started to move toward the north.  Florence will move into western Carolina on Sunday night.  It will move over eastern Tennessee, western Virginia, eastern Kentucky, and West Virginia on its way toward Ohio on Monday.  One primary rainband on the eastern side of the circulation will continue to drop heavy rain over parts of eastern South Carolina for a few more hours.  Convergence into the low will produce heavy rain that could move into western Virginia and West Virginia on Monday.  Flash Flood Watches have been issued for South Carolina, North Carolina, western Virginia and southern West Virginia.

Tropical Storm Florence Still Dropping Heavy Rain on the Carolinas

Tropical Storm Florence was still dropping heavy rain on parts of the Carolinas on Saturday.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Florence was located at latitude 33.6°N and longitude 79.9°W which put it about 45 miles (75 km) south-southwest of Florence, South Carolina.  Tropical Storm Florence was moving toward the west at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 997 mb.  A Tropical Storm Warning was in effect for the portion of the coast from South Santee River, South Carolina to Surf City, North Carolina.

Although the inner core of Tropical Storm Florence continues to spin down slowly, the circulation covers much of North Carolina, South Carolina, and eastern Georgia.  The center and much of the circulation around Florence is over land, but strong inflow east of the center continues to transport moist air over North Carolina.  The strongest winds are occurring over the Atlantic Ocean in two rainbands east of the center.  Winds to tropical storm force extend out about 150 miles (240 km) east of the center of circulation over the Atlantic Ocean.  The winds over North Carolina and South Carolina are generally blowing at less than tropical storm force.  Thunderstorms in some rainbands could produce gusts to tropical storm force.

Tropical Storm Florence has moved very slowly toward the west during the past 24 hours.  The extremely slow motion has allowed bands of showers and thunderstorms to persist over locations and rainfall totals have exceed a foot (0.3 meters) in some places.  Parts of the Cape Fear River and Trent River have already reached major flood levels.  Portions of the Neuse River are at moderate flood levels.  Sections of Interstates 95 and 40 are closed because of high water.

The high pressure system that has been blocking a northward movement of Tropical Storm Florence will start to shift to the east on Sunday.  The eastward movement of the high will allow Tropical Storm Florence to move a little faster and turn toward the northwest.  Florence could be over western North Carolina on Sunday evening.  Wind blowing up the eastern slopes of the will enhance rainfall.  Tropical Storm Florence will continue to drop heavy rain over North Carolina and South Carolina on Sunday.  The heavy rain could cause rivers and streams to go higher.

Elsewhere over the Atlantic Ocean, Tropical Storm Helene neared the Azores, Tropical Storm Isaac weakened to a tropical wave over the Caribbean Sea and Tropical Storm Joyce was pulled northeast in the wake of Helene.  At 5:00 p.m. EDT on Saturday the center of Tropical Storm Helene was located at latitude 40.2°N and longitude 32.1°W which put it about 75 miles (120 km) northwest of Flores, Azores.  Helene was moving toward the northeast at 24 m.p.h. (39 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 989 mb.  A Tropical Storm Warning was in effect for all of the Azores.

At 5:00 p.m. EDT on Saturday the center of Tropical Storm Joyce was located at latitude 33.1°N and longitude 39.6°W which put it about 785 miles (1260 km) west-southwest of the Azores.  Joyce was moving toward the east-northeast at 17 m.p.h. (28 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 1002 mb.

Hurricane Florence Makes Landfall Near Wilmington, North Carolina

Hurricane Florence made landfall near Wilmington, North Carolina on Friday morning.  The National Hurricane Center stated that the center of Hurricane Florence officially made landfall near Wrightsville Beach or about five miles east of Wilmington at 7:15 a.m. EDT on Friday.  The maximum sustained wind speed was 90 m.p.h. (145 km/h) at the time of landfall.  Hurricane Florence moved slowly toward the west after landfall.

At 2:00 p.m. EDT on Friday the center of Hurricane Florence was located at latitude 34.0°N and longitude 78.4°W which put it about 35 miles (55 km/h) east-northeast of Myrtle Beach, South Carolina.  Florence was moving toward the west at 5 m.p.h. (8 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 968 mb.

A Hurricane Warning was in effect for the portion of the coast from South Santee River, South Carolina to Bogue Inlet, North Carolina including Pamlico Sound.  Tropical Storm Warnings were in effect for the portions of the coast from Edisto Beach, South Carolina to South Santee River and from Bogue Inlet to Duck, North Carolina including Albemarle Sound.

Hurricane Florence did produce sustained winds to hurricane force when hit North Carolina.  A National Data Buoy Center C-MAN station (CLKN7) reported a sustained wind speed of 81 m.p.h. (131 km/h) and a wind gust of 101 m.p.h. (163 km/h).  A buoy east of the center of Hurricane Florencereported a wind gust of 112 m.p.h. (180 km/h) near the time of landfall.  The airport at Wilmington, North Carolina reported a wind gust of 87 m.p.h. (140 km/h).

The center of Hurricane Florence has been inland for a few hours and the circulation is gradually spinning down.  There is still a well organized center of circulation, but they eye has filled in with clouds and showers.  The strongest winds are occurring in rainbands that are still out over the Atlantic Ocean.  Friction is reducing the wind speed in the part of the circulation over land.

Hurricane Florence continues to pose serious risks for southeastern North Carolina and eastern South Carolina.  A prolonged period of tropical storm force winds and occasional gusts to hurricane force could bring down trees and add to the widespread power outages.  On the eastern side of Hurricane Florence the wind will push water toward the shore and the threat of coastal flooding continues.  Bands of showers and thunderstorms will drop heavy rain and flash flooding is likely near rivers and streams that are already at bankful.

Elsewhere over the Atlantic Ocean, Tropical Storm Helene was speeding toward the Azores, Tropical Depression Isaac was moving over the eastern Caribbean Sea and Tropical Storm Joyce was moving west of Helene.

At 11:00 a.m. EDT on Friday the center of Tropical Storm Helene was located at latitude 32.9°N and longitude 36.3°W which put it about 655 miles (1055 km) southwest of the Azores.  Helene was moving toward the north  at 23 m.p.h. (37 km/h).  The maximum sustained wind speed was 70 m.p.h. (110km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 988 mb.  A Tropical Storm Warning was in effect for all of the Azores.

At 11:00 a.m. EDT on Friday the center of Tropical Depression Isaac was located at latitude 14.9°N and longitude 67.3°W.  Isaac was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 35 m.p.h. (55km/h) and there were wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1007 mb.

At 11:00 a.m. EDT on Friday the center of Tropical Storm Joyce was located at latitude 31.6°N and longitude 44.6°W which put it about 1090 miles (1755 km) west-southwest of the Azores.  Joyce was moving toward the south at 8 m.p.h. (13 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 1003 mb.

Hurricane Florence Wobbles Closer to North Carolina

Hurricane Florence wobbled closer to the coast of North Carolina on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Hurricane Florence was located at latitude 34.0°N and longitude 76.8°W which put it about 60 miles east-southeast of Wilmington, North Carolina.  Florence was moving toward the northwest at 6 m.p.h.  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surface pressure was 956 mb.

A Hurricane Warning was in effect for the portion of the coast from South Santee River, South Carolina to Duck, North Carolina including Pamlico and Albemarle Sounds.  A Tropical Storm Warning was in effect for the portion of the coast from Edisto Beach to South Santee River, South Carolina.  A Tropical Storm Warning was also in effect for the portion of the coast from Duck, North Carolina to Cape Charles Light, Virginia and for Chesapeake Bay south of New Point Comfort.

Hurricane Florence is already affecting the coast.  National Data Buoy Center C-MAN station CLKN7 at Cape Lookout, North Carolina reported a sustained wind speed of 81 m.p.h. (131 km/h) and a wind gust of 101 m.p.h. (163 km/h).  Storm surges were already occurring along portions of the coast east of the center of Hurricane Florence where the winds were pushing water toward the coast.  The highest surge appeared to be in the area of the western part of Pamlico Sound near the mouth of the Neuse River.  There were scattered reports of wind damage and power outages.

A high pressure system over the northeastern U.S. is blocking the northward movement of Hurricane Florence.  The high is steering Florence slowly toward the northwest.  On its anticipated track Hurricane Florence will make a landfall near Wilmington, North Carolina on Friday.  Florence could move a little south of due west after landfall.  The center will pass a little north of Myrtle Beach, South Carolina and then move toward Columbia, South Carolina.  Florence is likely to continue to weaken slowly.  Because of the slow movement, many locations will experience extended periods of gusty winds.  Power outages are likely to become more widespread on Friday.  Hurricane Florence will drop locally heavy rain.  Locations where rainbands are essentially station could receive over a foot (0.3 meters) of rain.  Serious fresh water flooding is likely to develop on Friday and Saturday.

Elsewhere over the Atlantic Ocean, Tropical Storm Helene generated a Tropical Storm Watch for all of the Azores, Tropical Storm Isaac sped across the eastern Caribbean Sea and former Subtropical Storm Joyce made a transition to Tropical Storm Joyce.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Helene was located at latitude 28.6°N and longitude 36.5°W which put it about 885 miles (1425 km) southwest of the Azores.  Helene was moving toward the north at 21 m.p.h. (34 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were gusts to 80 m.p.h. (130km/h).  The minimum surface pressure was 992 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Isaac was located at latitude14.9°N and longitude 64.4°W which put it about 195 miles (315 km) south of St. Croix.  Isaac was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1006 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Joyce was located latitude 32.9°N and longitude 44.4°W which put it about 1040 miles (1670 km) west-southwest of the Azores.  Joyce was moving toward the south-southwest at 7 m.p.h. (11 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 1003 mb.

Hurricane Florence Moves Closer to the Carolinas

Hurricane Florence moved closer to the Carolinas on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Florence was located at latitude 32.0°N and longitude 73.7°W which put it about 280 miles (455 km) east-southeast of Wilmington, North Carolina.  Florence was moving toward the northwest at 17 m.p.h. (28 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 957 mb.

A Hurricane Warning was in effect for the portion of the coast from South Santee River, South Carolina to Duck, North Carolina including Pamlico and Albemarle Sounds.  A Hurricane Watch was in effect for the portion of the coast from Edisto Beach, South Carolina to South Santee River, South Carolina.  A Tropical Storm Warning is in effect for the portion of coast from Duck, North Carolina to the North Carolina-Virginia border.  A Tropical Storm Watch was in effect for the portion of the coast from the North Carolina-Virginia border to Cape Charles Light, Virginia and for Chesapeake Bay south of New Point Comfort.

The wind speed in Hurricane Florence decreased on Wednesday but the circulation increased in size.  It appeared that another eyewall replacement cycle could have started.  Satellite microwave images suggested that there could be two eyewalls and a reconnaissance plane reported a double wind maxima.  Both of those things could be evidence of concentric eyewalls.  In addition, counterclockwise flow around a small upper level low near Florida may have produced southerly winds that blew toward the south side of Hurricane Frances.  Those winds may have inhibited the upper level divergence to the south of Florence.  Since the hurricane was unable to pump out as much mass, the surface pressure increased and the wind speed decreased.

The circulation of Hurricane Florence increased in size on Wednesday.  Winds to hurricane force extended out about 80 miles (130 km) from the center of circulation.  Winds to tropical storm force extended out about 200 miles (320 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Florence was 19.2.  The Hurricane Size Index (HSI) was 25.5 and the Hurricane Wind Intensity Size Index (HWISI) was 44.7.  Those indices are very similar to the numbers for Hurricane Jeanne just before Jeanne made landfall in southeast Florida in 2004.

Hurricane Florence will move through an environment favorable for intensification on Thursday.  Florence will move over water where the Sea Surface Temperature is near 29°C.  Florence will move farther away from the upper low near Florida and the low should not inhibit divergence to the south of the hurricane as much.  In addition, Hurricane Florence will move over the warm water in the Gulf Stream about 6 to 12 hours before it reaches the coast.  It will be able to extract extra energy at that time.  If the inner core becomes more organized, then Hurricane Florence could intensify on Thursday.  If the inner core does not get better organized, then Florence will likely maintain its current intensity or weaken slowly.

Hurricane Florence will move near the western end of the subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence toward the northwest on Thursday.  On its anticipated track the center of Hurricane Florence will be near the coast of North Carolina on Thursday night.  A ridge over the eastern U.S. is likely to block the northward motion of Hurricane Florence when it reaches the coast.  The ridge will steer Florence slowly toward the west-southwest on Friday and Saturday.

Hurricane Florence will have the impact of a major hurricane regardless of the actual sustained wind speed.  The large circulation and slow rate of movement when Florence reaches the coast means that locations could experience strong winds for extended periods of time.  Wind damage and power outages could be extensive.  Some places in North Carolina had a rainy summer and strong winds could uproot trees.  Hurricane Florence will produce a dangerous storm surge along the coast.  The surge could exceed 10 feet (3 meters) in some locations east of where the center makes landfall.  The slow forward speed also means that Hurricane Florence could drop locally heavy rain and severe flooding could occur.

Elsewhere the rest of the Atlantic Ocean was also very active.  Tropical Storm Isaac was nearing the Lesser Antilles, Hurricane Helene was weakening south of the Azores and Subtropical Storm Joyce formed northwest of Helene.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Isaac was located at latitude 15.3°N and longitude 58.0°W which put it about 220 miles (355 km) east of Dominica.  Isaac was moving toward the west at 20 m.p.h. (32 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 1006 mb.  Tropical Storm Warnings were in effect for Guadeloupe, Martinique and Dominica.  Tropical Storm Watches were in effect for Antigua, Montserrat, St, Kitts and Nevis, Saba and St. Eustatius, St. Martin and St. Maarten.

At 11:00 p.m. EDT on Thursday the center of Hurricane Helene was located at latitude 22.4°N and 36.9°W which put it about 1270 mile (2045 km) south-southwest of the Azores.  Helene was moving toward the north at 13 m.p.h. (20 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. (155 km/h).  The minimum surface pressure was 983 mb.

At 11:00 p.m. EDT on Thursday the center of Subtropical Storm Joyce was located at latitude 15.3°N and longitude 46.6°W which put it about 910 miles (1465 km) west-southwest of the Azores.  Joyce was moving toward the southwest at 6 m.p.h. (10 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 1006 mb.

Hurricane Warnings Issued for Carolinas for Hurricane Florence

Hurricane Warnings were issued for the Carolinas on Tuesday for the potential impacts of Hurricane Florence.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Florence was located at latitude 28.4°N and longitude 68.7°W which put it about 670 miles (1075 km) east-southeast of Cape Fear, North Carolina.  Florence was moving toward the west-northwest at 17 m.p.h. (28 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 946 mb.

A Hurricane Warning was in effect for the portion of the coast from South Santee River, South Carolina to Duck, North Carolina.  Hurricane Watches were in effect for the portions of the coast from Edisto Beach to South Santee River, South Carolina and from Duck, North Carolina to the North Carolina-Virginia border.  Tropical Storm Watches were in effect for the portions of the coast from Duck, North Carolina to Cape Charles Light, Virginia and for Chesapeake Bay south of New Point Comfort.

Hurricane Florence completed an eyewall replacement cycle and it continues to be a powerful hurricane.  There was a circular eye with a diameter of 30 miles (48 km) at the center of Florence.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  The eyewall replacement cycle resulted in a larger circulation.

Winds to hurricane force extended out about 60 miles (95 km) from the center of circulation of Hurricane Florence.  Winds to tropical storm force extended out about 175 miles (280 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Florence was 28.2.  The Hurricane Size Index (HSI) was 18.9 and the Hurricane Wind Intensity Size Index (HWISI) was 47.1.  Hurricane Florence is capable of causing extensive significant damage.

Hurricane Florence will move through an environment favorable for strong hurricanes during the next 24 to 36 hours.  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.  Hurricane Florence is likely to maintain its intensity and it could strengthen.  If another eyewall replacement cycle occurs, then there could be fluctuations in intensity.

Hurricane Florence will move around the western end of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Florence toward the west-northwest during the next 24 to 36 hours.  On its anticipated track Hurricane Florence could approach the coast of the Carolinas later on Thursday.  The steering winds are forecast to weaken when Florence nears the coast and there is great uncertainty about the track when that occurs.  Hurricane Florence will bring strong winds to coastal North Carolina and eastern South Carolina.  Wind pushing water toward the shore will cause a significant storm surge.  A slow forward speed will mean that Hurricane Florence will drop a lot of rain and there is a risk of significant flooding of rivers and streams.

Elsewhere over the Atlantic Ocean, Tropical Storm Isaac was speeding toward the Lesser Antilles and Hurricane Helene was weakening far south of the Azores.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Isaac was located at latitude 14.5°N and longitude 52.3°W which put it about 580 miles (935 km) east of Martinique.  Isaac was moving toward the west at 16 m.p.h. (26 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 999 mb.  Tropical Storm Warnings were in effect for Dominica, Martinique and Guadeloupe.  Tropical Storm Watches were in effect for Antigua, Montserrat, St. Kitts and Nevis, and Saba and St. Eustatius.

At 11:00 p.m. EDT on Tuesday the center of Hurricane Helene was located at latitude 18.0°N and longitude 35.4°W which put it about 1479 miles (2370 km) south-southwest of the Azores.  Helene was moving toward the northwest at 10 m.p.h. (16 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 973 mb.