Tag Archives: AL15

Tropical Storm Odette Forms South of New England

Tropical Storm Odette formed south of New England on Friday afternoon. At 5:00 p.m. EDT on Friday the center of Tropical Storm Odette was located at latitude 36.7°N and longitude 71.8°W which put it about 325 miles (525 km) south-southwest of Nantucket, Massachusetts. Odette was moving toward the northeast 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 1010 mb.

A new circulation center developed on the northern side of a larger low pressure system over the Atlantic Ocean south of New England on Friday afternoon and the National Hurricane Center designated the system as Tropical Storm Odette. The low level center of Odette was surrounded by lower clouds and showers. Thunderstorms were occurring in bands on the northern and eastern periphery of Tropical Storm Odette. Bands in the other parts of Odette’s circulation consisted primarily of showers and lower clouds. An upper level trough over the eastern U.S. was producing southwesterly winds that were blowing across the top of Tropical Storm Odette. Those winds were causing moderate vertical wind shear and the wind shear was contributing to the asymmetrical distribution of thunderstorms. Winds to tropical storm force extended out 115 miles (185 km) on the eastern side of Odette. The winds on the western side of the circulation were blowing at less than tropical storm force.

Tropical Storm Odette will move through an environment that is somewhat favorable for intensification during the next 36 hours. Odette will move over water in the Gulf Stream where the Sea Surface Temperatures are near 28˚C. The upper level trough over the eastern U.S. will continue to cause vertical wind shear, but the shear could decrease on Saturday. Tropical Storm Odette could strengthen during the next 24 hours. Odette will move over cooler water later in the weekend when it moves north of the Gulf Stream. Tropical Storm Odette will make a transition to an extratropical cyclone when it moves over cooler water. Odette could strengthen during the transition to an extratropical cyclone.

The upper level trough over the eastern U.S. will steer Tropical Storm Odette toward the northeast during the next 48 hours. On its anticipated track Tropical Storm Odette will pass southeast of Cape Cod. Odette could approach southeastern Newfoundland by late in the weekend.

Tropical Storm Nana Moves Over Guatemala

Tropical Storm Nana moved over Guatemala on Thursday.  At 2:00 p.m. EDT on Thursday the center of Tropical Storm Nana was located at latitude 16.3°N and longitude 90.6°W which put it about 120 miles (195 km) north of Guatemala City, Guatemala.  Nana was moving toward the west t 14 m.p.h. (22 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.

After making landfall in southern Belize as a hurricane on Wednesday night, Tropical Storm Nana moved westward over northern Guatemala.  The small circulation around Nana weakened steadily on Thursday.  Tropical Storm Nana was dropping locally heavy rain over Guatemala on Thursday afternoon.  The heavy rain could cause flash floods in some locations.

Tropical Storm Nana will weaken to a tropical depression within a few hours.  Nana will continue to move toward the west.  It could emerge over the Gulf of Tehuantepec on Friday.

Elsewhere over the Atlantic Ocean, Tropical Depression Omar moved away from Bermuda.  At 11:00 a.m. EDT on Thursday the center of Tropical Depression Omar was located at latitude 35.9°N and longitude 61.1°W which put it about 335 miles (540 km) northeast of Bermuda.  Omar was moving toward the east 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 1005 mb.

Nana Strengthens to a Hurricane Near Belize

Former Tropical Storm Nana strengthened into a hurricane as it neared a landfall in Belize.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Nana was located at latitude 17.0°N and longitude 87.5°W which put it about 60 miles (95 km) southeast of Belize City, Belize.  Nana was moving toward the west at 16 m.p.h. (26 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 994 mb.

A Hurricane Warning was in effect for the portion of the coast from Belize City to the Belize/Guatemala border.  A Hurricane Watch was in effect for the portion of the coast from Belize City to the Belize/Mexico border.  A Tropical Storm Warning was in effect for the portion of the coast from Belize City to Belize/Mexico border.  A Hurricane Warning was also in effect for the portion of the coast from Puerto Costa Maya to Chetumal, Mexico.  Tropical Storm Warnings were in effect for the Caribbean Sea coast of Guatemala, Isla Roatan and the Bay Islands.  A Tropical Storm Watch was in effect for the north coast of Honduras from Punta Patuca to the border with Guatemala.

Former Tropical Storm Nana moved into a more favorable environment on Wednesday night and strengthened to a hurricane.  More thunderstorms formed near the center of circulation and those thunderstorms helped to spin up the circulation.  Since the circulation around Hurricane Nana was relatively small, it was able to spin up into a hurricane in a few hours.  Winds to hurricane force extended out 15 miles (25 km) on the northern side of Nana.  Winds to tropical storm force only extended out 70 miles (110 km) from the center of circulation.

Hurricane Nana has a few more hours when it could strengthen before it makes landfall in southern Belize.  Nana will move over water where the Sea Surface Temperature is near 30°C.  It will move through a region where the upper level winds are weak and there will be less vertical wind shear.  Hurricane Nana could get a little stronger.

Hurricane Nana will move south of a subtropical high pressure system over the western Atlantic Ocean.  The high will steer Nana a little to the south of due west.  On its anticipated track Hurricane Nana will make landfall on the coast of Belize south of Belize City early on Wednesday morning.  Nana will be capable of causing localized wind damage.  It could cause a storm surge of up to eight feet (2.6 meters) along the south coast of Belize.  Hurricane Nana will drop heavy rain over parts of southern Belize and northern Guatemala.  Flash floods could occur in some locations.

Elsewhere over the North Atlantic Ocean, former Tropical Storm Omar weakened to a tropical depression north of Bermuda.  At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Omar was located at latitude 36.1°N and longitude 64.1°W which put it about 265 miles (425 km) north of Bermuda.  Omar was moving toward the east 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 1005 mb.

Tropical Storm Nana Strengthens, Hurricane Watch Issued for Belize

Tropical Storm Nana strengthened on Tuesday night and a Hurricane Watch was issued for Belize.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Nana was located at latitude 17.0°N and longitude 80.9°W which put it about 485 miles (775 km) east of Belize City, Belize.  Nana was moving toward the west at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were wind gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 999 mb.

A Hurricane Watch was issued for the entire coast of Belize.  A Tropical Storm Warning was also in effect for Belize.  A Tropical Storm Warning was in effect for the portion of the coast from Puerto Costa Maya to Chetumal, Mexico.  Tropical Storm Watches were in effect for the Caribbean Sea coast of Guatemala and for the north coast of Honduras from Punta Patuca to the border with Guatemala including Roatan Island and the Bay Islands.

Tropical Storm Nana continued to strengthen on Tuesday night.  There were signs that a small eye might be starting to form in the lower levels of the atmosphere.  More thunderstorms formed near the center of circulation.  Storms near the center generated upper level divergence which pumped mass away from the tropical storm.  Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation.

Tropical Storm Nana will move through an environment favorable for intensification during the next 24 hours.  Nana 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 Nana is likely to intensify into a hurricane on Wednesday.

Tropical Storm Nana will move south of a subtropical high pressure system over the Atlantic Ocean.  The high will steer Nana toward the west during the next 24 to 36 hours.  On its anticipated track the center of Tropical Storm Nana will pass north of Honduras.  Nana could approach Belize on Wednesday night.

Elsewhere over the Atlantic Ocean, Tropical Storm Omar continued to move away from North Carolina.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Omar was located at latitude 35.8°N and longitude 70.0°W which put it about 310 miles (500 km) east of Cape Hatteras, North Carolina.  Omar was moving toward the east-northeast at 14 m.p.h. (22 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.

Tropical Depression Fifteen Forms South of Cape Hatteras

Tropical Depression Fifteen formed south of Cape Hatteras on Monday afternoon.  At 5:00 p.m. EDT on Monday the center of Tropical Depression Fifteen was located at latitude 32.6°N and longitude 76.5°W which put it about 190 miles (305 km) south-southwest of Cape Hatteras, North Carolina.  The depression was moving toward the northeast at 12 m.p.h. (19 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.

An Air Force Reserve Hurricane Hunters’ reconnaissance flight found that there was a closed low level circulation in a low pressure system south of Cape Hatteras and the National Hurricane Center designated the system as Tropical Depression Fifteen.  The circulation around Tropical Depression Fifteen was still organizing.  Bands of showers and thunderstorms were revolving around the low level center of circulation.  Storms near the center started to generate upper level divergence which pumped mass away to the east of the tropical depression.

Tropical Depression Fifteen will move through an environment somewhat favorable for intensification during the next day or two.  The depression will move over water where the Sea Surface Temperature is near 28.5°C.  It will move near the southern periphery of the upper level westerly winds in the middle latitudes.  Those winds will blow toward the top of the depression and they will cause moderate vertical wind shear.  The shear will inhibit intensification, but it will not be enough to prevent the depression from strengthening.  Tropical Depression Fifteen will likely strengthen into a tropical storm.

Tropical Depression Fifteen will move around the northern side 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 the depression will move away from the U.S. and it will pass north of Bermuda.

Tropical Depression Fifteen Forms Southeast of Cabo Verde Islands

Tropical Depression Fifteen formed southeast of the Cabo Verde Islands on Monday.  At 5:00 p.m. EDT on Monday the center of Tropical Depression Fifteen was located at latitude 13.2°N and longitude 20.2°W which put it about 320 miles (515 km) southeast of the Cabo Verde Islands.  The depression was moving toward the northwest at 8 m.p.h. (13 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.

A large, well developed low pressure system embedded in the northern end of a tropical wave moved over the Atlantic Ocean west of North Africa on Monday.  Bands of showers and thunderstorms began to strengthen when the low moved over water and the National Hurricane Center designated the system as Tropical Depression Fifteen.  Bands of showers and thunderstorms were revolving around the center of the depression.  Storms closer to the center were generating upper level divergence which was pumping mass away from Tropical Depression Fifteen.  The circulation around the depression was quite large.  The diameter of the low level circulation was about 500 miles (800 km).

Tropical Depression Fifteen will move through an environment favorable for intensification during the next 24 to 48 hours.  The depression will move over water where the Sea Surface Temperature is near 28°C.  It will move under the western end of an upper level ridge centered over North Africa.  The upper level winds will be weak and there will be little vertical wind shear during the next day or two.  Tropical Depression Fifteen is likely to strengthen into Tropical Storm Nestor.

The ridge over North Africa will steer Tropical Depression Fifteen toward the northwest during the next several days.  On its anticipated track the center of the depression could reach the Cabo Verde Islands within 24 hours.  Since the depression is forecast to strengthen into a tropical storm watches and/or warnings could be issued.

Elsewhere over the Atlantic Ocean, Tropical Storm Melissa completed a transition to an extratropical cyclone on Monday.  At 11:00 a.m. EDT on Monday the center of Tropical Storm Melissa was located at latitude 41.0°N and longitude 51.4°W which put it about 405 miles (650 km) south-southeast of Cape Race, Newfoundland.  Melissa was moving toward the east at 23 m.p.h. (37 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 1004 mb.

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.

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.