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.

Potential Tropical Development Near East Coast of U.S.

There is the potential for the development of a tropical cyclone near the East Coast of the U.S. during the next several days.  A low pressure system, currently designated as Invest 98L developed over the northern Gulf of Mexico during the weekend.  The low moved slowly toward the northeast across the southeastern U.S.  At 2:00 a.m. EDT on Wednesday the low level center of Invest 98L was located at latitude 33.3°N and longitude 80.5°W which put it about 25 miles (40 km) west of Charleston, South Carolina.  The low was moving toward the east at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 25 m.p.h. (40 km/h) and there were wind gusts to 35 m.p.h. (55 km/h).  The minimum surface pressure was 1013 mb.

Invest 98L currently consists primarily of a lower level circulation.  Much of the circulation is over land and the center is west of Charleston, South Carolina.  Many of the bands revolving around the center of the low pressure system consist of showers and lower clouds.  There are bands of showers and thunderstorms on the far eastern edge of the circulation which is over the Gulf Stream.  An upper level trough over the southeastern U.S. is producing westerly winds which are blowing across the top of the low level circulation.

Invest 98L will move into an environment more favorable for the development of a tropical cyclone.  It will move over water where the Sea Surface Temperature is near 27°C when the center moves over the Atlantic Ocean.  The upper level trough will over the southeastern U.S. will cause moderate vertical wind shear.  The wind shear will inhibit development.  If thunderstorms develop closer to the center of circulation, those storms could cause the circulation grow vertically into the middle and upper troposphere.  If the thunderstorms release enough latent energy in the middle and upper troposphere, a warm core could form and Invest 98L could become a tropical cyclone.

The National Hurricane Center indicated in the 8:00 a.m. EDT Tropical Weather Outlook on Wednesday that the probability was 70% that a tropical or subtropical cyclone could form during the next five days.  An upper level trough approaching the eastern U.S. will steer the low pressure system toward the north-northeast during the next few days.  On its anticipated track the low pressure system will move near the East Coast of the U.S.  A reconnaissance aircraft is tentatively scheduled to investigate Invest 98L later on Wednesday, if necessary.

Tropical Storm Cristina Forms South of Acapulco

Tropical Storm Cristina formed south of Acapulco on Monday.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Cristina was located at latitude 11.2°N and longitude 101.3°W which put it about 405 miles (650 km) south-southwest of Acapulco, Mexico.  Cristina was moving toward the west-northwest at 15 m.p.h. (24 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 distinct low pressure center organized quickly in a tropical wave south of Mexico on Monday.  Satellite images showed a well developed counterclockwise rotation around the center of circulation.  Bands of showers and thunderstorms were revolving around the center of Tropical Storm Cristina.  The inner end of a rainband wrapped around the southern and eastern sides of the center of circulation.  Storms near the center of circulation were generating upper level divergence which was pumping mass away in all directions from the tropical storm,  Winds to tropical storm force extended out about 35 miles (55 km) from the center of Cristina.

Tropical Storms Cristina will move through an environment favorable for intensification during the next several days.  Cristina will move over water where the Sea Surface Temperature is near 29.5°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Tropical Storm Cristina will continue to strengthen and it could intensify rapidly.  Cristina will intensify into a hurricane within 36 hours and it could strengthen into a major hurricane later this week.

Tropical Storm Cristina will move around the southwestern part of a ridge of high pressure over Mexico and the southwestern U.S.  The ridge will steer Cristina toward the west-northwest during the next few days.  On its anticipated track Tropical Storm Cristina will move away from the west coast of Mexico.

Tropical Depression Five Strengthens into Tropical Storm Edouard

Former Tropical Depression Five strengthened into Tropical Storm Edouard northeast of Bermuda on Sunday night.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Edouard was located at latitude 37.2°N and longitude 56.9°W which put it about 685 miles (1100 km) south-southwest of Cape Race, Newfoundland.  Edouard was moving toward the northeast at 35 m.p.h. (56 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 1008 mb.  Tropical Storm Edouard became the earliest fifth named storm to form over the Atlantic Ocean during the satellite era since 1966.

Former Tropical Depression Five exhibited greater organization on satellite imagery and the National Hurricane Center designated the system as Tropical Storm Edouard.  More thunderstorms formed in bands east of the center of circulation.  Bands in the northern and western parts of Edouard consisted primarily of showers and lower clouds.  Winds to tropical storm force were occurring within 60 miles of the center in the southeastern quadrant of Tropical Storm Edouard.  The winds in the other parts of Edouard were blowing at less than tropical storm force.

Tropical Storm Edouard will move through an environment that could allow for a little more intensification during the next 12 hours.  Edouard will move over water where the Sea Surface Temperature is near 24°C.  It will move under the southern fringe of the upper level westerly winds in the middle latitudes.  Those winds will blow toward the top of the circulation and they will cause moderate vertical wind shear.  The relatively cool water temperatures and moderate vertical wind shear will limit future intensification.  Tropical Storm Edouard could get a little stronger on Monday.  Edouard will move over cooler water later on Monday and it will start a transition to an extratropical cyclone.

Tropical Storm Edouard will move around the northern side of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Edouard toward the northeast.  On its anticipated track Tropical Storm Edouard will pass well south of Newfoundland.

Tropical Depression Five Forms West-southwest of Bermuda

Tropical Depression Five formed west-southwest of Bermuda on Saturday morning.  At 11:00 a.m. EDT on Saturday the center of Tropical Depression Five was located at latitude 31.1°N and longitude 68.7°W which put it about 245 miles (390 km) west-southwest of Bermuda.  The depression was moving toward the east-northeast at 17 m.p.h. (28 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 1009 mb.

Visible satellite images showed that a small low pressure system west-southwest of Bermuda exhibited more organization on Saturday morning and the National Hurricane Center designated the system as Tropical Depression Five.  The circulation around Tropical Depression Five was small but it was fairly well organized.  The depression had a well defined center of circulation.  Thunderstorms were occurring in bands south and east of the center.  Bands in the northwestern part of Tropical Depression Five consisted primarily of showers and lower clouds.  Storms near the center of circulation were generating upper level divergence which was pumping mass away to the east of the depression.

Tropical Depression Five will move through an environment somewhat favorable for intensification during the next 12 to 24 hours.  The depression will move over water where the Sea Surface Temperature is near 25.5°C.  It will move under the southern edge of the upper level westerly winds in the middle latitudes.  Those winds will cause moderate vertical wind shear, but the shear may not be strong enough to prevent some intensification.  Tropical Depression Five could strengthen into a tropical storm during the next 24 hours.

Tropical Depression Five will move around the northwestern part of a subtropical high pressure system over the Atlantic Ocean.  The high will steer the depression toward the east-northeast during the next several days.  On its anticipated track Tropical Depression Five will move near Bermuda on Saturday night.  The depression could be a tropical storm when it passes by Bermuda.

Tropical Depression Four-E Forms Southwest of Baja California

Tropical Depression Four-E formed just southwest of Baja California on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Depression Four-E was located at latitude 20.5°N and longitude 112.6°W which put it about 240 miles (385 km) southwest of the southern tip of Baja California.  The depression was moving toward the northwest 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 1004 mb.

The circulation around a low pressure system southwest of Baja California exhibited more organization on Monday night and the National Hurricane Center designated the system as Tropical Depression Four-E.  The distribution of thunderstorms around the depression was asymmetrical.  A band of stronger thunderstorms wrapped around the northern side of the center of circulation.  The strongest winds were occurring in that band of storms.  Bands in other parts of the depression consisted of primarily of showers and lower clouds.

Tropical Depression Four-E will move into an environment mostly unfavorable for intensification.  The depression will move over water where the Sea Surface Temperature is near 24.5°C.  An upper level trough over the western U.S. and an upper level ridge over Mexico will produce southwesterly winds which will blow toward the top of the depression.  Those winds will cause moderate vertical wind shear.  The colder water and moderate shear will prevent the potential for significant intensification.  The depression could maintain its intensity during the next six to twelve hours but it is likely to weaken later on Tuesday.

Tropical Depression Four-E will move around the western end of a ridge of high pressure over Mexico.  The ridge will steer the depression slowly toward the northwest.   On its anticipated track Tropical Depression Four-E will pass west of Baja California.

Tropical Storm Boris Develops East-Southeast of Hawaii

Tropical Storm Boris developed east-southeast of Hawaii on Thursday afternoon.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Boris was located at latitude 11.2°N and longitude 137.1°W which put it about 1330 miles (2145 km) east-southeast of Hilo, Hawaii.  Boris was moving toward the west-northwest at 9 m.p.h. (15 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.

More thunderstorms developed Thursday afternoon near a low pressure system southeast of Hawaii that was previously designated as Tropical Depression Three-E.  A scatterometer on board a satellite detected winds to 40 m.p.h. (65 km) near the center of the low pressure system and the National Hurricane Center designated the system as Tropical Storm Boris.  A band of showers and thunderstorms wrapped around the southern and eastern sides of the center of circulation and the strongest winds were occurring in that band of storms.  A few other short bands of showers and thunderstorms developed in the eastern half of Boris.  Bands in the western half of the circulation consisted primarily of showers and lower clouds.  Winds to tropical storm force extended out about 50 miles from the center of circulation.

Tropical Storm Boris will move through an environment marginally favorable for intensification during the next 12 to 24 hours.  Boris will move over water where the Sea Surface Temperature is near 26.5°C.  A large upper level trough between Hawaii and the West Coast of the U.S. will produce southwesterly winds which will blow toward the top of the circulation.  Those winds will cause moderate vertical wind shear and the shear will limit intensification.  In addition, there is drier air north and west of Tropical Storm Boris.  Boris could intensify during the next 12 hours in spite of the moderate vertical wind shear and drier air.  However, Tropical Storm Boris will move into a region where the upper level winds are stronger during the weekend.  When the vertical wind shear increases, Boris will weaken.

Tropical Storm Boris will move south of a subtropical high pressure system over the Eastern North Pacific Ocean.  The will steer Boris toward the west-northwest during the next 24 hours.  When Tropical Storm Boris weakens during the weekend, it will be steered by winds closer to the surface.  Those winds will steer Boris toward the west.  On its anticipated track the weakening Tropical Storm Boris will pass southeast of Hawaii.

Tropical Storm Dolly Develops Southwest of Newfoundland

Tropical Storm Dolly developed southwest of Newfoundland on Tuesday.  At 1:00 p.m. EDT on Tuesday the center of Tropical Storm Dolly was located at latitude 39.4°N and longitude 61.9°W which put it about 660 miles (1065 km) southwest of Cape Race, Newfoundland.  Dolly was moving toward the east-northeast at 13 m.p.h. (20 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. (5 km/h).  The minimum surface pressure was 1002 mb.

Former Subtropical Depression Four strengthened on Tuesday and its structure continued to make a transition to a more tropical cyclone like appearance.  A band of showers and thunderstorms wrapped closely around the southern side of the center of circulation.  The strongest winds were occurring in that band.  Other bands of showers and thunderstorms were revolving around the center of circulation.  A scatterometer on board a satellite estimated that there were winds above tropical storm force and the National Hurricane Center designated the system as Tropical Storm Dolly.  The winds to tropical storm force extended out 65 miles (105 km) on the southern side of Dolly.  The winds in the other parts of the circulation were generally blowing at less than tropical storm force.

Tropical Storm Dolly will move through an environment that could be favorable for intensification during the next 6 to 12 hours.  Dolly will move near the northern part of the Gulf Stream where the water is near 26°C.  It will move around the southeastern part of a weakening upper level low.  The upper low will produce some vertical wind shear, but the shear will not be strong enough to prevent intensification during the next 6 to 12 hours.  Tropical Storm Dolly is likely to move north of the Gulf Stream on Wednesday.  When Dolly moves over colder water it will start to weaken.

Tropical Storm Dolly will move around the southeastern side of the upper low during the next few hours.  The upper low will weaken on Wednesday and both the upper low and Dolly will be steered toward the northeast by a larger upper level trough over eastern North America.  On its anticipated track Tropical Storm Dolly could bring gusty winds and rain to southeastern Newfoundland on Wednesday night and Thursday.

Subtropical Depression Four Forms Southeast of Cape Cod

Subtropical Depression Four developed southeast of Cape Cod, Massachusetts on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Subtropical Depression Four was located at latitude 38.2°N and longitude 65.7°W which put it about 310 miles (495 km) southeast of Cape Cod, Massachusetts.  The depression was moving toward the east-northeast 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 1009 mb.

The structure of a previously non-tropical low pressure system southeast of Cape Cod evolved into a more symmetrical circular shape on Monday.  Bands of showers and thunderstorms revolved more closely around the center of the low.  The low pressure system exhibited a more tropical like structure on visible satellite imagery.  However, the National Hurricane Center (NHC) observed that the surface low was under an upper low which meant the system had a cold core in the upper troposphere.  So, NHC designated the system as Subtropical Depression Four when it initiated advisories on Monday afternoon.

The circulation around Subtropical Depression Four had a hybrid structure with a tropical like appearance in the lower levels and a non-tropical cold core in the upper levels.  The depression will move through an environment favorable for intensification during the next 12 to 18 hours.  The core of the depression will move near the northern part of the Gulf Stream where the Sea Surface Temperature is near 26°C.  It will move near the south side of the core of the upper low where the winds are weaker.  Those winds will cause some vertical wind shear, but the shear will not be too strong during the next 12 hours.  The depression could strengthen into a subtropical storm.  There is a chance that the circulation could develop a warm core in the upper levels if the depression stays near the Gulf Stream.  The warm water in the Gulf Stream and the cold air in the upper troposphere will enhance instability which will contribute to the development of thunderstorms.  If thunderstorms release enough latent energy in the upper troposphere, then a warm core could form and the system could make an additional transition into a tropical storm.

Subtropical Depression Four is likely to move in tandem with the upper low during the next day or two.  The upper low will move toward the east-northeast on Tuesday and then it will move more toward the northeast on Wednesday.  On its anticipated track Subtropical Depression Four will move away from the northeast U.S.  The depression will remain south of Nova Scotia, but it could pass near southeastern Newfoundland on Thursday.

Weakening Tropical Depression Nuri Makes Landfall West of Hong Kong

A weakening Tropical Depression Nuri made landfall on the coast of China west of Hong Kong on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Depression Nuri was located at latitude 22.2°N and longitude 111.5°E which put it about 170 miles (280 km) west of Hong Kong.  Nuri was moving toward the northwest at 18 m.p.h. (29 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 1001 mb.

Former Tropical Storm Nuri weakened to a tropical depression as it approached the coast of China on Saturday night.  An upper level ridge centered over China produced northeasterly winds which blew toward the top of former Tropical Storm Nuri.  Those winds caused moderate vertical wind shear and they blew the tops off thunderstorms in the eastern half of Nuri.  The wind shear blocked upper level divergence to the east of the tropical storm and the surface pressure increased.  The wind speed decreased and Nuri was downgraded to a tropical depression as it neared the coast of China.

Tropical Depression Nuri moved around the southwestern part of a subtropical high pressure system over the Western North Pacific Ocean.  The high steered Nuri toward the northwest.  Tropical Depression Nuri made landfall on the coast of China west of Hong Kong.  The center of Nuri crossed the coast between Dianbai and Yangjiang.  The circulation around Tropical Depression Nuri will continue to weaken as it moves farther inland.  Nuri will bring some heavy rain showers to parts of southeastern China before it dissipates.