Monthly Archives: September 2017

Tropical Storm Maria Brings Gusty Winds, Big Waves to Outer Banks

Tropical Storm Maria brought gusty winds and big waves to the Outer Banks of North Carolina on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Maria was located at latitude 34.9°N and longitude 72.9°W which put it about 150 miles (240 km) east of Cape Hatteras, North Carolina.  Maria was moving toward the north at 7 m.p.h. (11 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 975 mb.

A Tropical Storm Warning is in effect for the portion of the coast from Bogue Inlet, North Carolina to the North Carolina/Virginia border including Albemarle and Pamlico Sounds.

Most of the showers and thunderstorms are occurring in the eastern half of the circulation of Tropical Storm Maria.  The strongest winds are also occurring in the eastern half of Maria.  Winds to tropical storm force extend out about 230 miles (370 km) east of the center of circulation and about 185 miles (295 km) to the west of the center.  A NOAA buoy (41025) at Diamond Shoals was reporting sustained winds to near tropical storm force.  The large size and slow movement of Tropical Storm Maria were causing large waves that were reaching the Outer Banks of North Carolina.

Tropical Storm Maria is moving around the western end of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Maria slowly toward the north on Wednesday.  An upper level trough approaching the eastern U.S. will start to steer Maria toward the east on Thursday.  The upper level trough will push Tropical Storm Maria away from the U.S. on Friday.  When Maria moves over cooler water it will make a transition to an extratropical cyclone.

Elsewhere over the Atlantic Ocean, small Hurricane Lee neared major hurricane intensity.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Lee was located at latitude 30.0°N and longitude 55.5°W which put it about 570 miles (920 km) east-southeast of Bermuda.  Lee was moving toward the west at 9 m.p.h. (15 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 971 mb.

Hurricane Lee has a small, well organized circulation.  There is a small eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms.  Several bands of showers and thunderstorms are revolving close to the core of Hurricane Lee.  Winds to hurricane force only extend out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force extend out about 60 miles (95 km) from the center.

Hurricane Lee could intensify into a major hurricane on Wednesday.  Lee will move over water where the Sea Surface Temperature is near 28°C.  The upper level winds will be weak on Wednesday and there will be little vertical wind shear.  Wind shear will increase later in the week when the upper level trough approaching the eastern U.S. gets closer to Hurricane Lee.

Hurricane Maria Weakens As It Moves Over Jose’s Cold Wake

Hurricane Maria weakened on Sunday as it moved over an area of cooler water mixed to the surface by Hurricane Jose last week.  At 11:00 p.m. EDT on Sunday the center of Hurricane Maria was located at latitude 30.0°N and longitude 73.0°W which put it about 385 miles (625 km) south-southeast of Cape Hatteras, North Carolina.  Maria was moving toward the north at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 90 m.p.h. (150 km/h) and there were wind gusts to 105 m.p.h. (165 km/h).  The minimum surface pressure was 950 mb.

A Tropical Storm Watch was in effect for the portion of the coast from Surf City, North Carolina to the North Carolina/Virginia border including Albemarle and Pamlico Sounds.

Hurricane Maria is moving over an area traversed by Hurricane Jose a week ago.  The winds of Jose mixed cooler water to the surface.  The region of cooler water is sometimes called the cold wake because it is left behind after a hurricane passes over a section of the ocean.  Observations from a NOAA research aircraft indicate that the Sea Surface Temperatures beneath Hurricane Maria are 24°C to 25°C.  There is not enough energy in the upper ocean to support a major hurricane and the circulation of Hurricane Maria has weakened during the past 24 hours.  The clouds around the eye and in the rainbands are not as tall.

Even though the upper level winds are not too strong and there is not much vertical wind shear, Hurricane Maria is unlikely to intensify.  Maria will continue to move over cooler water mixed to the surface by Jose.  Maria is likely to continue to weaken slowly during the next day or two.  Maria is a large hurricane and winds to tropical storm force extend out about 230 miles (370 km) from the center.

Maria is moving around the western end of subtropical high over the Atlantic Ocean.  The high is steering Maria toward the north and that general motion is expected to continue for several more days.  On its anticipated track Hurricane Maria would be southeast of Cape Hatteras on Tuesday night.  When Maria gets closer to the Outer Banks of North Carolina, the hurricane will reach the westerly flow in middle latitudes.  Those westerly winds are forecast to steer Hurricane Maria toward the east later this week.

Because of the large size of Hurricane Maria’s circulation, winds to tropical storm force could be near the Outer Banks even if the center of Maria remains offshore.  Maria will also generate large waves and significant beach erosion could occur.

Tropical Storm Pilar Forms Near Mexico

Tropical Storm Pilar formed just west of Mexico on Saturday.  At 11:00 p.m. EDT on Saturday the center of Tropical Storm Pilar was located at latitude 18.7°N and longitude 105.3°W which put it about 120 miles (195 km) south-southeast of Cabo Corrientes, Mexico.  Pilar was moving toward the north 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 1003 mb.

A Tropical Storm Warning was issued for the portion of the coast from Manzanillo to El Roblito including the Islas Marias.

A distinct center of circulation developed within a larger area of low pressure near the west coast of Mexico on Saturday and the system was classified as Tropical Storm Pilar.  Several bands of showers and thunderstorms began to form around the center.  Storms near the center started to generate upper level divergence which was pumping mass away to the west of Tropical Storm Pilar.

Tropical Storm Pilar will move through an environment that will be somewhat favorable for intensification on Sunday.  Pilar will move over water where the Sea Surface Temperature is near 29°C.   An upper level high over Mexico is producing easterly winds which are blowing toward the top of the circulation.  Those winds are producing some vertical wind shear, but the shear was not strong enough to prevent the formation of Tropical Storm Pilar.  The eastern part of the circulation will be moving over western Mexico and increased friction will be the primary factor inhibiting strengthening.  Tropical Storm Pilar is likely to intensify on Sunday.

A ridge in the middle levels of the atmosphere over Mexico is steering Tropical Storm Pilar slowly toward the north.  On its anticipated track the center of Tropical Storm Pilar will be very near Cabo Corrientes on Sunday night.  The center could move inland or it could remain just west of the coast.  Tropical Storm Pilar will drop very heavy rain over parts of the states of Colima and Jalisco.  The heavy rain could cause flash flooding in some locations.

Hurricane Maria Pulls Away from the Turks and Caicos

Hurricane Maria pulled away slowly from the Turks and Caicos on Friday.  At 5:00 p.m. EDT on Friday the center of Hurricane Maria was located at latitude 23.3°N and longitude 71.4°W which put it about 395 miles (635 km) east-southeast of Nassau, Bahamas.  Maria was moving toward the north-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 959 mb.

Tropical Storm Warnings were in effect for the Turks and Caicos, Southeastern Bahamas and Central Bahamas.

The structure of Hurricane Maria did not change much on Friday.  An eye continued to mark the center of circulation.  A nearly complete ring of thunderstorms surrounded the eye.  The strongest winds were occurring in that ring of storms.  Bands of showers and thunderstorms revolved around the core of Hurricane Maria.  There were more showers and thunderstorms in the northern half of the circulation.  Winds to hurricane force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Hurricane Maria will move through an environment that is somewhat favorable for hurricanes.  Maria will move over water where the Sea Surface Temperature is near 29°C.  An upper level trough over the southeastern U.S. is producing southwesterly winds which are blowing toward the top of the circulation.  Those winds are not producing strong vertical wind shear, but they could impede upper level divergence to the west of Hurricane Maria.  Hurricane Maria could maintain its intensity for another day or two unless the vertical shear increases. If the shear increases, then Maria will start to weaken.

Hurricane Maria has reached the western end of the subtropical high pressure system over the Atlantic Ocean.  The high is steering Maria toward the north-northwest.  A general north-northwesterly motion is expected to continue for several more days.  On its anticipated track the core of Hurricane Maria will pass east of the Bahamas.

Major Hurricane Maria Moves Slowly Toward the Turks and Caicos

Major Hurricane Maria moved slowly toward the Turks and Caicos on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Hurricane Maria was located at latitude 21.0°N and longitude 80.2°W which put it about 65 miles (110 km) east-southeast of the Turks and Caicos.  Maria was moving toward the northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 125 m.p.h. (205 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  The minimum surface pressure was 955 mb.

Hurricane Warnings were in effect for the Turks and Caicos, the Southeastern Bahamas and the portion of the coast from Cabo Engano to Puerto Plata, Dominican Republic.  Tropical Storm Warnings are in effect for portion of the coast from Puerto Plata, Dominican Republic to the northern border with Haiti.  Tropical Storm Watches are in effect for the Central Bahamas.

The core of Hurricane Maria reorganized on Thursday as the center moved over the warm water north of the Dominican Republic.  A large eye formed at the center of circulation.  The eye had a diameter of 40 miles (64 km).  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 Maria.  Crossing over Puerto Rico and an eyewall replacement cycle produced a larger circulation.  Winds to hurricane force extended out about 70 miles (110 km) from the center of circulation.  Winds to tropical storm force extended out about 160 miles (260 km) from the center.

Hurricane Maria will move through an environment favorable for strong hurricanes.  Maria will move over water where the Sea Surface Temperatures are near 29°C.  Hurricane Maria will remain in an area where the upper level winds are weak and there is likely to be little vertical wind shear for at least one more day.  The outer portion of the southern half of Hurricane Maria’s circulation is still passing over the Dominican Republic.   Additional friction in the part of the circulation passing over land could reduce the amount of intensification that occurs.  Hurricane Maria is likely to strengthen on Friday and it could reach Category 4 on the Saffir-Simpson Scale.

Hurricane Maria is nearing the western end of the subtropical high pressure system which is steering the hurricane toward the northwest.  Maria is entering an area where the steering currents are weaker and the motion of the hurricane slowed on Thursday night.  The numerical models are still forecasting that Hurricane Maria will turn north on Friday when it rounds the western end of the high pressure system.  Hurricane Maria is moving a little farther west than has been forecast and that trend could continue on Friday.  If Hurricane Maria does move farther west than anticipated, then the core of Maria could come very close to the Turks and Caicos and parts of the Southeastern Bahamas.

Even if the center of Hurricane Maria does not pass directly over the Turks and Caicos and Southeastern Bahamas, bands of showers and thunderstorms will bring gusty winds and locally heavy rain.  Maria will also cause a storm surge on the coasts of those islands.  If the center of Maria passes directly over them, the hurricane is capable of causing major damage.  The southern part of Maria’s circulation is bringing heavy rain to parts of the Dominican Republic and there is the potential for flash floods.

Hurricane Maria Moves Away from Puerto Rico

Hurricane Maria moved away from Puerto Rico on Wednesday night after causing significant wind damage and serious flash floods.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Maria was located at latitude 19.2°N and longitude 67.9°W which put it about 55 miles (85 km) northeast of Punta Cana, Dominican Republic.  Maria was moving toward the northwest at 9 m.p.h. (15 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 959 mb.

Hurricane Warnings are in effect for the Turks and Caicos, the Southeastern Bahamas, and the portion of the coast from Cabo Engano to Puerto Plata, Dominican Republic.  A Hurricane Watch is in effect for the portion of the coast from Cabo Engano to Isla Saona, Dominican Republic.  Tropical Storm Warnings are in effect for the portions of the coast from Puerto Plata to the northern border with Haiti and from Cabo Engano to Punta Palenque, Dominican Republic.

Hurricane Maria made landfall on the southeast coast of Puerto Rico near Yabucoa on Wednesday morning.  Maria was a Category 4 hurricane on the Saffir-Simpson Scale at the time of landfall.  Hurricane Maria moved northwest across Puerto Rico and the center emerged over the Atlantic Ocean near Arecibo on Thursday afternoon.

Hurricane Maria weakened as the core of the hurricane moved across Puerto Rico.  The mountains on Puerto Rico disrupted the circulation in the lower levels of Maria, but the middle and upper portions of the circulation remained intact.  Hurricane Maria was in the middle of an eyewall replacement cycle when it made landfall in Puerto Rico.  The timing of landfall may have caused Maria to weaken more than it would have if there had not been an eyewall replacement cycle.  The inner eyewall which contained the strongest winds dissipated at Hurricane Maria moved across Puerto Rico.  The strongest winds are occurring in the remaining outer eyewall.  The eyewall replacement cycle contributed to an increase in the size of the circulation of Hurricane Maria.  Wind to hurricane force extend out about 60 miles (95 km) from the center of circulation.  Wind to tropical storm force extend out about 160 miles (260 km) from the center.

Hurricane Maria will move through an environment favorable for intensification on Thursday.  Maria will move over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is not much vertical wind shear.  It could take another 12 to 24 hours for the lower portions of the circulation to reorganize.   The reorganization could limit the rate of intensification.  In addition the center will pass near the Dominican Republic.  Some of the southern part of the circulation will be over land and that could also limit intensification until Maria moves farther away from Hispaniola.

Hurricane Maria is moving around the southwestern portion of the subtropical high over the Atlantic Ocean.  That high has been steering Maria toward the northwest.  Many of the numerical models are forecasting that the high will weaken and Maria will turn toward the north on Thursday.  If the high remains stronger than the models are forecasting, then Hurricane Maria will move farther toward the west.  Hurricane Maria seems to have moved near the left side of the guidance from the numerical models in recent days.  On its forecast track the center of Hurricane Maria will move north of the Dominican Republic on Thursday.  Hurricane Maria could be near the Turks and Caicos on Friday.

Hurricane Maria is still capable of producing extensive significant damage.  Maria will drop heavy rain on parts of the Dominican Republic and there could be flash floods in some places where there is steeper terrain.

Elsewhere, Tropical Storm Jose move slowly east-northeast southeast of Massachusetts.  At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Jose was located at latitude 39.5°N and longitude 68.2°W which put it about 150 miles (245 km) southeast of Nantucket.  Jose was moving toward the east-northeast at 6 m.p.h. (9 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were ind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 982 mb.  A Tropical Storm Warning was in effect for the portion of the coast from Woods Hole to Sagamore Beach including Block Island, Martha’s Vineyard, Nantucket and Cape Cod.

Category 5 Hurricane Maria Bearing Down on Puerto Rico

Category 5 Hurricane Maria was bearing down on Puerto Rico on Tuesday night.  The eye was very near St. Croix.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Maria was located at latitude 17.3°N and longitude 64.7°W which put it about 30 miles (45 km) south-southeast of St. Croix and about 120 miles (190 km) southeast of San Juan, Puerto Rico.  Maria was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 175 m.p.h. (280 km/h) and there were wind gusts to 215 m.p.h. (345 m/h).  The minimum surface pressure was 909 mb.

Hurricane Warnings were in effect for Puerto Rico, Culebra, Vieques, the U.S. Virgin Islands, the British Virgin Islands, and for the portion of the coast from Cabo Engano to Puerto Plata, Dominican Republic.  Hurricane Watches were in effect for the Turks and Caicos, the Southeastern Bahamas, Saba, St. Maarten, St. Martin, St. Eustatius, St. Barthelemy, and the portion of the coast from Isla Saona to Cabo Engano, Dominican Republic.  Tropical Storm Warnings were in effect for Saba, St. Eustatius, St. Maarten, the portion of the coast from Puerto Plata,, Dominican Republic to the northern border with Haiti and for the portion of the coast from Cabo Engano to Punta Palenque, Dominican Republic,

Hurricane Maria is a very well organized powerful hurricane.  It has a small inner eye and a second outer eyewall extends most of the way around the inner eyewall.  The strongest winds are occurring in the inner eyewall.  Additional spiral bands are revolving around the core of the circulation.  The concentric eyewalls have caused the circulation of Hurricane Maria to increase in size.  Winds to hurricane force now extend out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extend out about 160 miles (260 km) from the center.

The Hurricane Intensity Index (HII) for Hurricane Maria is 40.4.  The Hurricane Size Index (HSI) is 19.2 and the Hurricane Wind Intensity Size Index (HWISI) is 59.6.  Those indices indicate that Hurricane Maria is capable of causing regional catastrophic damage.

Hurricane Maria will continue to move through an environment favorable for powerful hurricanes until it reaches Puerto Rico.  Maria will move over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  If the outer eyewall completely encircles the inner eyewall, then an eyewall replacement cycle could cause some weakening.  Hurricane Maria will weaken more if the center moves directly over Puerto Rico.  The amount of weakening will depend on the stage of the eyewall replacement cycle at the time of landfall.

Hurricane Maria is being steered toward the west-northwest by the subtropical high pressure system over the Atlantic Ocean.  The western end of the high is forecast to weaken during the next several days.  The weakening of the high will allow Hurricane Maria to move more toward the north.  The core of Hurricane Maria will pass near or over St. Croix during the next few hours.  On its anticipated track Hurricane Maria will reach Puerto Rico on Wednesday morning.

Hurricane Maria is a very dangerous hurricane.  It is capable of causing catastrophic damage.  Maria will also drop very heavy rain over Puerto Rico and there is the potential for significant flash flooding.  Maria could also cause a storm surge of up to 12 feet (4 meters) along the coast.

Elsewhere, Hurricane Jose weakened to a tropical storm east of the U.S.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Jose was located at latitude 37.9°N and longitude 70.8°W which put it about 230 miles (375 km) south of Nantucket.  Jose was moving toward the northeast at 9 m.p.h. (15 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 973 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Woods Hole to Sagamore Beach, Massachusetts including Block Island, Martha’s Vineyard, Nantucket and Cape Cod.  A Tropical Storm Watch was in effect for the portion of Long Island from Fire Island Inlet to Port Jefferson.

Hurricane Maria Strengthens to Cat. 5 Near Leeward Islands

Hurricane Maria quickly strengthened to a Category 5 hurricane on the Saffir-Simpson Scale on Monday.  At 8:00 p.m. EDT on Monday the center of Hurricane Maria was located at latitude 15.3°N and longitude 61.1°W which put it about 15 miles (25 km) east-southeast of Dominica.  Maria was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 160 m.p.h. (260 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 925 mb.

Hurricane Warnings were in effect for Puerto Rico, Culebra, Vieques, Dominica, Guadeloupe, St. Kitts, Nevis, Martinique, Montserrat, the U.S. Virgin Islands and the British Virgin Islands.  Hurricane Watches were in effect for Saba, St. Eustatius, St. Maarten, Anguilla, St. Martin, St. Barthelemy and the portion of the coast from Isla Saona to Puerto Plata, Dominican Republic.  Tropical Storm Warnings were in effect for Anguilla, St. Lucia, Antigua, Barbuda, Saba, St. Eustatius and St. Maarten.  Tropical Storm Watches were in effect for St. Vincent, the Grenadines and the portion of the coast from Puerto Plata to the Haiti/Dominican Republic border.

Hurricane Maria has a tight compact circulation.  There is a small eye with a diameter of 10 miles (16 km) at the center of circulation.  The eye is surround by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.  Additional bands of showers and thunderstorms are revolving around the core of Maria.  The overall circulation of Hurricane Maria is small.  Winds to hurricane force only extend out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force only extend out about 125 miles (200 km) from the center.

The Hurricane Intensity Index (HII) for Hurricane Maria is 35.0.  The Hurricane Size Index (HSI) is 9.1 and the Hurricane Wind Intensity Size Index (HWISI) is 44.1.

Hurricane Maria will continue to move through an environment very favorable for strong hurricanes.  Maria will move over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear.  Hurricane Maria could strengthen further.  Since the eye of Hurricane Maria is so small, it would be easy for a rainband to wrap around the eye.  If that happens, then an eyewall replacement cycle could begin and the cycle could result in a temporary weakening of the hurricane.

Hurricane Maria is being steered to the west-northwest by the subtropical high pressure system over the Atlantic Ocean.  That high is forecast to weaken and Maria is likely to move more toward the northwest during the next several days.  On its anticipate track the center of Hurricane Maria will pass very close to Dominica and Guadeloupe on Monday night.  Maria could pass near Montserrat, St. Kitts and Nevis on Tuesday.  It could be near the U.S. Virgin Islands on Tuesday night and Hurricane Maria will approach Puerto Rico on Wednesday.

Hurricane Maria is a small but very dangerous hurricane.  The winds in the core of Hurricane Maria are capable of causing extensive damage.  In addition, heavy rain falling over steep terrain will likely produce flash floods.  Hurricane Maria will affect some of the same islands that were severely damaged by Hurricane Irma.  Maria will significantly hamper efforts in some places to recover from the effects of Hurricane Irma.

Elsewhere over the Atlantic Ocean, Hurricane Jose has begun the transition to an extratropical cyclone as it moves northward off the east coast of the U.S.  At 5:00 p.m. EDT on Monday the center of Hurricane Jose was located at latitude 34.8°N and longitude 71.1°W which put it about 445 miles (720 km) south of Nantucket, Massachusetts.  Jose was moving toward the north 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 977 mb.

A Tropical Storm Warning was in effect for the portion of the coast from Watch Hill, Rhode Island to Hull, Massachusetts including Block Island, Martha’s Vineyard and Nantucket.  Tropical Storm Watches were in effect for the portion of the coast of Long Island from Fire Island Inlet to Port Jefferson and from New Haven, Connecticut to Watch Hill, Rhode Island.

The structure of Hurricane Jose began to change on Monday from the more circular shape of a purely tropical hurricane to an asymmetrical shape seen more commonly in extratropical cyclones.  Drier air wrapped around the western and southern sides of the circulation.  Most of the strong thunderstorms and heavy rain were occurring in the northern half of Jose.  Winds to hurricane force extended out about 60 miles (95 km) north of the center, but there were few if any winds to hurricane force south of the center.  The circulation of Hurricane Jose is much larger than the circulation of Hurricane Maria.  Winds to tropical storm force extend out about 320 miles (515 km) from the center of Jose.

The Hurricane Intensity Index for Hurricane Jose was 10.4.  The Hurricane Size Index for Jose was 15.6 and the Hurricane Wind Intensity Size Index was 26.0.

Hurricane Jose will move into an environment that is unfavorable for hurricanes on Tuesday.  Jose will stay over warm Sea Surface Temperatures until it moves north of the Gulf Stream.  Once Jose moves north of latitude 38°N, it will start to move over cooler water.  An upper level trough over the eastern U.S. is producing southerly winds which are causing moderate vertical wind shear over Jose.  Cooler water and moderate shear would normally cause a hurricane to weaken.  However, as Hurricane Jose makes the transition to an extratropical cyclone, it will start to be powered by the temperature difference between warm and cold air.  The transition to an extratropical cyclone can sometimes produce a stronger storm when it occurs.

Hurricane Jose is moving around the western end of the subtropical high.  Another surface high pressure system is forecast to move north of Jose when the hurricane approaches the northeastern U.S.  The second high will block the northward motion and it will force Hurricane Jose to move toward the east.  Some models are forecasting that Jose could make a clockwise loop southeast of Cape Cod.  Hurricane Jose could bring gusty winds and high waves to sections of the coast in the northeastern U.S. during the next few days.

Tropical Storm Norma Drifts Near Baja California, Otis Rapidly Intensifies to Cat. 2 Hurricane

Tropical Storm Norma drifted near Baja California on Sunday, while Hurricane Otis rapidly strengthened into a Category 2 hurricane on the Saffir-Simpson Scale.  At 8:00 p.m. EDT on Sunday the center of Tropical Storm Norma was located at latitude 21.3°N and longitude 111.2°W which put it about 140 miles (220 km) south-southwest of Cabo San Lucas, Mexico.  Norma was moving toward the northwest at 6 m.p.h. (9 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 1001 mb.

A Tropical Storm Watch was in effect for the portion of the coast from Los Barriles to Todos Santos, Mexico.

Tropical Storm Norma retains some of the structural features that it had when it was a hurricane.  The remnants of a large circular eye form the center of circulation.  A broken ring of strong thunderstorms surrounds the remnants of the eye and the strongest winds are occurring in that ring.  Bands of showers and weaker thunderstorms are revolving around the core of Tropical Storm Norma.  Some of the outer rainbands of Norma are already dropping heavy rain over parts of the southern end of Baja California.

Tropical Storm Norma will move through an environment that will be only marginally favorable for intensification during the next day or so.  Norma will move over water where the Sea Surface Temperature is near 28°C.  An upper level trough west of North America is producing southwesterly winds which are blowing toward the top of the circulation.  Those winds are causing moderate vertical wind shear.  The circulation of Norma may also be drawing some cooler more stable air into the western part of the tropical storm.  Tropical Storm Norma could intensify somewhat during the next 24 hours, but it will eventually move over cooler water and weaken.

A ridge in the middle troposphere located east of Norma is steering the tropical storm toward the northwest and that general motion is expected to continue for another day or so.  When Norma weakens, it will be steered by the winds in the lower levels of the atmosphere.  Those winds will push Tropical Storm Norma more toward the west during the middle of the weak.  On its anticipated track the center of Tropical Storm Norma is forecast to remain west of Baja California.

Hurricane Otis intensified very rapidly on Sunday from a weak tropical storm to a Category 2 hurricane on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Sunday the center of Hurricane Otis was located at latitude 17.0°N and longitude 127.3°W which put it about 1200 miles (1930 km) west-southwest of the southern tip of Baja California.  Otis was moving toward the north at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 973 mb.

Hurricane Otis has a very small circulation, which allowed to strengthen very rapidly when the environment became more favorable.  A small eye formed at the center of Hurricane Otis and a tight ring of very strong thunderstorms surrounded the eye.  Those storms began generating upper level divergence which pumped mass away from the center of circulation.  The pressure decreased quickly and the wind speed increased very rapidly.  Hurricane Otis still has a small circulation.  Winds to tropical storm force only extend out about 70 miles (110 km) from the center.

Hurricane Otis may be near its peak intensity.  Otis is still moving over water where the Sea Surface Temperature is near 27°C, but it will soon move over cooler water.  Hurricane Otis will move nearer to the upper level trough west of North America and the hurricane will encounter stronger vertical wind shear.  Because Otis is a small hurricane, it could weaken almost as fast as it intensified.

A small midlevel ridge east of Otis is steering the hurricane toward the north.  Much like Tropical Storm Norma, Otis will be steered by winds lower in the atmosphere when it weakens.  Those winds are forecast to steer Otis more toward the west-southwest later this week.

Maria Becomes a Hurricane, Jose Prompts Watches for Northeast U.S.

A reconnaissance plane found that Tropical Storm Maria had intensified into a hurricane as it moved toward the Leeward Islands on Sunday afternoon.  At the same time Hurricane Jose moved farther north and Tropical Storm Watches were issued for the coast of the northeastern U.S.  At 5:00 p.m. EDT on Sunday the center of Hurricane Maria was located at latitude 13.8°N and longitude 57.5°W which put it about 275 miles (445 km) east-southeast of Dominica.  Maria was moving toward the west-northwest at 15 m.p.h. (24 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. (150 km/h).  The minimum surface pressure was 982 mb.

Hurricane Warnings were in effect for Guadeloupe, Dominica, St. Kitts, Nevis and Montserrat.  Hurricane Watches were in effect for the U.S. Virgin Islands, the British Islands, Saba, St. Eustatius, St. Maarten, St. Martin, St. Barthelemy, and Anguilla.  Tropical Storm Warnings were in effect for Martinique, St. Lucia, Antigua, Barbuda, Saba, and St. Eustatius.  Tropical Storm Watches were in effect for Barbados, St. Vincent and the Grenadines.

A reconnaissance plane found sustained winds to hurricane force when it investigated Hurricane Maria on Sunday afternoon.  The plane reported a circular eye with a diameter of 32 miles (52 km) at the center of circulation.  The eye was surrounded by an almost complete ring of thunderstorms.  The ring was broken south of the center.  The strongest winds wind occurring in that ring of thunderstorms.  Additional bands of showers and thunderstorms were developing in the eastern half of the circulation.  There were fewer showers and thunderstorms in the western half of Maria.  Hurricane Maria was generating upper level divergence which was pumping away mass and allowing the surface pressure to decrease.

Hurricane Maria will move through an environment that will be favorable for intensification.  Maria will move over water where the Sea Surface Temperature is near 29°C.  An upper level low over Caribbean Sea is causing southern winds which are blowing near the eastern side of Hurricane Maria.  Those winds do not appear to be causing significant vertical wind shear.  Hurricane Maria is likely to continue to intensify as it moves toward the Leeward Islands.  Maria could intensify rapidly once a fully closed eye develops.

Hurricane Maria is being steered toward the west-northwest by the subtropical high pressure system over the Atlantic Ocean and that general motion is expected to continue for several more days.  On its anticipated track Hurricane Maria could reach the Leeward Islands by later on Monday.  Maria could be near Puerto Rico by Wednesday.  Hurricane Maria will affect some of the same islands damaged by Hurricane Irma a few days ago.  Strong winds and heavy rain will significantly impact recovery efforts in those areas.

A reconnaissance plane also found that Hurricane Jose was stronger on Sunday afternoon.  At 5:00 p.m. EDT on Sunday the center of Hurricane Jose was located at latitude 31.5°N and longitude 71.8°W which put it about 335 miles (535 km) southeast of Cape Hatteras, North Carolina.  Jose was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 90 m.p.h. (150 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 967 mb.

Tropical Storm Watches have been issued for the portions of the coast from Fenwick Island, Delaware to Sandy Hook, New Jersey and from East Rockaway Inlet, New York to Plymouth, Massachusetts including Long Island Sound, Block Island, Martha’s Vineyard and Nantucket.

Hurricane Jose strengthened on Sunday as it moved over water where the Sea Surface Temperature was near 29°C.  An eye appeared at times on visible satellite imagery.  The circulation of Hurricane Jose increased in size which often happens when hurricanes move north out of the tropics.  Winds to hurricane force extended out about 60 miles (95 km) from the center of circulation.  Winds to tropical storm force extended out about 290 miles (470 km) from the center.

Hurricane Jose will move through an environment which will be marginal for further intensification.  Jose will move over water which is warm enough to support intensification.  However, an upper level trough over the eastern U.S. is producing southerly winds which are blowing toward the top of the circulation.  Those winds are producing strong vertical wind shear and they could weaken Jose during the next several days.  Jose will be moving over warm water until it gets north of the Gulf Stream.  If the upper level winds slow, then Jose could get stronger.

Hurricane Jose is being steered northward by the subtropical high over the Atlantic Ocean and the trough over the eastern U.S.  On its anticipated track the center of Jose is forecast to move toward the northeastern U.S. and turn toward the east before it reaches the coast.  If Jose follows the forecast track, then the core of the hurricane would remain offshore.  However, the circulation of Jose is large enough that even if the center stays offshore, there could still be tropical storm force winds along the coast.