Gert Intensifies to a Hurricane West of Bermuda

Gert intensified to a hurricane west of Bermuda on Monday.  Gert became the second Atlantic hurricane of 2017 and it is the second hurricane to form during the past six days.  Hurricane Franklin developed over the southern Gulf of Mexico last week.  At 11:00 p.m. EDT on Monday the center of Hurricane Gert was located at latitude 31.2°N and longitude 72.3°W which put it about 445 miles (720 km) west of Bermuda.  Gert was moving toward the north at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 986 mb.

An eye appeared on satellite images of Hurricane Gert at various times on Monday and it looked more like a hurricane.  There was a somewhat elliptical eye at the center of Hurricane Gert on Monday night.  The ring of thunderstorms around the eye did not completely surround the eye.  There was a large break on the northwest side of the eye.  Additional bands of showers and thunderstorms were occurring in the southeastern half of Gert.  There were fewer showers and thunderstorms in the northwestern half of the hurricane.  Thunderstorms near the core of Gert were generating upper level divergence which was pumping out mass to the south of the hurricane.

Hurricane Gert will be an environment that will be favorable for intensification for another 24 to 48 hours.  Gert will move over water where the Sea Surface Temperature is near 28.5°C.  An upper level ridge centered northwest of Gert is producing northerly winds which are blowing toward the top of the circulation.  Those winds are producing some vertical wind shear and they may be responsible for the asymmetrical distribution of showers and thunderstorms.  However, the vertical wind shear should not be strong enough to prevent Hurricane Gert from intensifying further.  An upper level trough will approach Gert from the west, but before the trough reaches the hurricane, the wind shear will decrease and a period of rapid intensification could occur.

Hurricane Gert is moving around the western end of a subtropical high over the Atlantic Ocean.  The high is steering Gert slowly toward the north.  When the upper level trough approaches Gert, southwesterly winds will start to steer the hurricane toward the northeast.  On its anticipated track Hurricane Gert should pass northwest of Bermuda.

TD 8 Strengthens to Tropical Storm Gert

Tropical Depression Eight strengthened to Tropical Storm Gert on Sunday afternoon.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Gert was located at latitude 28.1°N and longitude 71.7°W which put it about 505 miles (810 km) west-southwest of Bermuda.  Gert was moving toward the north-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1011 mb.

The structure of Tropical Storm Gert improved on Sunday.  Numerous bands of showers and thunderstorms developed and began to rotate around the center of circulation.  The thunderstorms began to produce upper level divergence which was pumping out mass in all directions.  The circulation of Tropical Storm Gert became more circular and symmetrical.

Tropical Storm Gert will move through an environment that will be favorable for intensification during the next 24 hours.  Gert will move over water where the Sea Surface Temperature is near 29°C.  The upper level winds over Tropical Storm Gert are weak and there is not much vertical wind shear.  There is an upper level ridge northwest of Tropical Storm Gert and the ridge is producing northeasterly winds west of Bermuda.  So, the vertical wind shear could increase when Gert moves farther north.  Tropical Storm Gert will continue to intensify during the next 24 hours.

Tropical Storm Gert is moving around the western end of the subtropical high pressure system over the Atlantic Ocean.  The high is steering Gert toward the north-northwest and a northerly motion is  expected to continue for another 24 hours.  When Gert moves west of Bermuda, it will start to encounter the westerly winds in the middle latitudes.  Those winds should turn Tropical Storm Gert toward the northeast in a day or so.  On its anticipated track Tropical Storm Gert is expected to move east of the U.S. and west of Bermuda.

Tropical Depression Eight Forms East of the Bahamas

Tropical Depression Eight formed east of the Bahamas on Saturday night.  At 11:00 p.m. EDT on Saturday the center of Tropical Depression Eight was located at latitude 25.3°N and longitude 70.3°W which put it about 470 miles (755 km) east of Nassau, Bahamas.  It was moving toward the north-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 gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1011 mb.

Data from satellites and NOAA buoy 41046 indicated that a low level center of circulation formed within former Invest 99L.  Based on those data the National Hurricane Center classified the system as Tropical Depression Eight.  Bands of showers and thunderstorms began to develop in Invest 99L on Saturday afternoon.  There were more bands in the eastern half of the circulation than there were in the western half.  Thunderstorms in the bands began to generate upper level divergence which was pumping away mass.  The circulation took on a more circular appearance and they system exhibited the characteristics of a tropical depression.

Tropical Depression Eight will move through an environment favorable for intensification during the next 36 to 48 hours.  It will move over water where the Sea Surface Temperature is near 30°C.  An upper low that was inhibiting the development of Invest 99L dissipated on Saturday.  When the upper low dissipated, the upper level winds weakened.  Tropical Depression Eight will move through an area where there is little vertical wind shear.  It will likely strengthen into Tropical Storm Gert on Sunday.  It could eventually intensify into a hurricane.

Tropical Depression Eight is moving around the western end of the subtropical high over the Atlantic Ocean.  The high is steering the depression toward the north-northwest and it is forecast to move primarily toward the north during the next 24 to 48 hours.  Tropical Depression Eight will eventually reach the westerly winds in the middle latitudes and it will turn toward the northeast when that happens.  On its anticipated track Tropical Depression Eight will remain east of the Bahamas.

Banyan Rapidly Intensifies Into a Typhoon

Tropical Storm Banyan rapidly intensified into a typhoon on Saturday.  At 5:00 p.m. EDT on Saturday the center of Typhoon Banyan was located at latitude 20.8°N and longitude 164.3°E which put it about 165 miles (265 km) west-northwest of Wake Island.  Banyan was moving toward the north-northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 115 m.p.h. (185 km/h).  The minimum surface pressure was 976 mb.

Banyan intensified rapidly from a tropical storm into a typhoon in less than 36 hours.  Banyan is a small well organized typhoon.  There is a small circular eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms.  The strongest winds are occurring in that ring of storms.  A primary band of thunderstorms wraps around the eastern and northern sides of the core of Typhoon Banyan.  Other bands of showers and storms are revolving around the core of the typhoon.  Banyan has a small circulation.  Winds to typhoon force only extend out about 25 miles (40 km) from the center of circulation.  Winds to tropical storm force only extend out about 100 miles (160 km) from the center.

Typhoon Banyan will continue to move through an environment that is favorable for intensification on Sunday.  Banyan will move over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Typhoon Banyan will continue to intensify during the next 24 hours and it could become the equivalent of a major hurricane.

Banyan is moving around the western end of a subtropical ridge, which is steering the typhoon toward the north-northwest.  Banyan is forecast to continue to move toward the north-northwest for another day or two.  On its anticipated track Typhoon Banyan will move away from Wake Island and the weather should improve on Sunday.

Tropical Storm Jova Develops South of Baja California

A center of circulation developed within the remnants of former Hurricane Franklin on Friday and the National Hurricane Center designated the low pressure system as Tropical Storm Jova.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Jova was located at latitude 19.3°N and longitude 109.8°W which put it 250 miles (400 km) south of the southern tip of Baja California.  Jova was moving toward the west-northwest 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.

The surface center of former Hurricane Franklin was disrupted as it passed over the mountains in Mexico.  However, the middle and upper portions of the circulation crossed the mountains relatively intact.  When the upper parts of the former hurricane emerged over the Eastern North Pacific Ocean, it took nearly a day for the vertical transfer of kinetic energy to spin up a new surface circulation.  Eventually a new surface circulation developed and the National Hurricane Center (NHC) classified the system as Tropical Storm Jova.  Established protocol is that when NHC ceases issuing an advisories on a tropical cyclone, the system is given a new name if it redevelops in a different basin.

The circulation of Tropical Storm Jova is broad, but winds to tropical storm force are occurring primarily in the northeastern quadrant of the circulation.  Most of the thunderstorms are occurring in a band that wraps around the western and southern sides of the center of circulation.  There are fewer thunderstorms in the eastern and northern sides of Tropical Storm Jova,  There is a broad counterclockwise circulation and a distinct center, but the horizontal structure is not well organized.

Tropical Storm Jova will be moving through an environment favorable for intensification during the next 24 hours.  Jova will move over water where the Sea Surface Temperature is near 30°C.  An upper lever ridge over northern Mexico is producing easterly winds which are blowing toward the top of the tropical storm.  Those winds are generating vertical wind shear.  The shear is moderate and it will inhibit intensification.  Tropical Storm is likely to intensify during the next 24 hours, but the broad circulation and vertical wind shear will limit the intensification.  In a day or two Tropical Storm Jova will move over cooler Sea Surface Temperatures and it will start to weaken.

A ridge in the middle levels is steering Tropical Storm Jova toward the west-northwest.  The ridge is expected to steer Tropical Storm Jova toward the west during the next several days.  On its anticipated track Tropical Storm Jova will move farther west of Mexico.

Tropical Storm Banyan Forms Near Wake Island

Tropical Storm Banyan formed quickly near Wake Island on Friday.  At 11:00 a.m. EDT on Friday the center of Tropical Storm Banyan was located at latitude 17.9°N and longitude 167.2°E which put it about 140 miles (225 km) south-southeast of Wake Island.  Banyan was moving toward the west-northwest 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 1003 mb.

The circulation of Tropical Storm Banyan organized quickly.  It developed a distinct center of circulation.  Thunderstorms formed north and south of the center, but there were more thunderstorms south of the center.  Additional bands of showers and thunderstorms began to develop in the outer parts of the circulation.  The thunderstorms in the core of Tropical Storm Banyan were generating upper level divergence which was pumping away mass.  The circulation of Tropical Storm Banyan is relatively small.  Winds to tropical storm force only extend out about 40 miles (65 km) from the center of circulation.

Tropical Storm Banyan will move through an environment that will be favorable for intensification.  Banyan will move over water where the Sea Surface Temperature is near 30.5°C.  An upper level ridge north of Banyan is producing easterly winds which are blowing toward the top of the circulation.  Those winds are weak and there is not much vertical wind shear.  Tropical Storm Banyan is likely to intensify during the next day or two and it could intensify quickly at times.

Tropical Storm Banyan is moving near the western end of a subtropical ridge to its north.  The ridge is currently steering Banyan toward the west-northwest, but the tropical storm is expected to turn more toward the north when it reaches the end of the ridge.  On its anticipated track Tropical Storm Banyan will move over Wake Island in about 12 hours.  Banyan will cause gusty winds and heavy rain when it moves over Wake Island.

Hurricane Franklin Brings Wind and Heavy Rain to Mexico

Hurricane Franklin brought gusty winds and heavy rain to parts of Mexico when it made landfall on Wednesday night.  The center of Hurricane Franklin made landfall between Veracruz and Nautla near the town of Lechuguillas, Mexico.  The maximum sustained wind speed was 85 m.p.h. (140 km) at the time of landfall, which made Franklin a Category 1 hurricane on the Saffir-Simpson Scale.  Franklin weakened to a tropical storm as it moved inland during the night.

At 8:00 a.m. EDT on Thursday the center of Tropical Storm Franklin was located at latitude 19.8°N and longitude 98.3°W which put it about 60 miles (95 km) east-northeast of the Mexico City, Mexico.  Franklin was moving toward the west 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 997 mb.

A Tropical Storm Warning remains in effect for the portion of the coast from Cabo Rojo to Boca Partido, Mexico.

Franklin brought hurricane force winds to the portion of the coast north of Veracruz, Mexico.  Those winds pushed water toward the shore and created a storm surge along the coast.  The highest surge may have reached 6 to 9 feet (2 to 3 meters) near and just to the north of where the center made landfall.  Winds blowing up the slopes of mountains produced very heavy rain and flooding could be occurring in some locations.  The heavy rain will continue as Tropical Storm Franklin moves west across central Mexico.

Tropical Storm Franklin will continue to weaken as it moves across Mexico.  Heavy rain will continue to fall over portions of central Mexico and the potential for additional flooding exists.  The mountains are likely to disrupt the low level circulation.  However, the middle and upper portions of the circulation could remain intact.  Some models are forecasting that Franklin, or its remnants, could redevelop when it reaches the Eastern North Pacific Ocean.

Franklin Strengthens Into a Hurricane Northeast of Veracruz

Formerly Tropical Storm Franklin strengthened into a hurricane northeast of Veracruz on Friday afternoon.  Franklin is the first hurricane to form over the Atlantic basin in 2017.  At 5:00 p.m. EDT the center of Hurricane Franklin was located at latitude 20.1°N and longitude 94.9°W which put it about 105 miles (170 km) northeast of Veracruz, Mexico.  Franklin was moving toward the west at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 75 m.p.h. (120 km/h) and there were gusts to 90 m.p.h. (145 km/h).  The minimum surface pressure was 984 mb.

A Hurricane Warning is in effect for the portion of the coast from Puerto de Veracruz to Cabo Rojo, Mexico.  A Hurricane Watch is in effect for the portion of the coast from Cabo Rojo to Rio Panuco.  A Tropical Storm Warning is in effect for the portion of the coast from Puerto Dos Bocas to Puerto de Veracruz and from Tuxpan to Barra del Tordo.

An elliptical eye formed at the center of Hurricane Franklin and a reconnaissance plane detected surface winds in excess of 74 m.p.h. (119 km/h).  Based on data from the plane and an improved appearance on satellite imagery, the National Hurricane Center upgrade Franklin to hurricane status in its 5:00 p.m. EDT advisory.

The structure of Hurricane Franklin improved on Friday.  An elliptical eye oriented north to south formed at the center of circulation.  A ring of thunderstorms completely surrounded the eye.  The strongest winds were occurring in the northeastern part of the ring of storms.  Storms in the core of the circulation were generating upper level divergence which was pumping out mass and allowing the surface pressure to decrease.  A primary band of showers and thunderstorms coiled inward toward the core of Hurricane Franklin,  Additional bands of showers and thunderstorms were revolving around the core of Franklin.  Winds to hurricane force extended out about 35 miles (55 km) northeast of the center of circulation.  Winds to tropical storm force extended out about 140 miles (225 km) on the northern side of Franklin and about 100 miles (160 km) on the southern side of the hurricane).

Hurricane Franklin could intensify further before it makes landfall.  It is moving over water where the Sea Surface Temperature is near 30°C.  An upper level ridge over northern Mexico is generating northerly winds which are blowing toward the top of the circulation.  However, those winds are not very strong and the vertical wind shear is minor and it did not prevent Franklin from becoming a hurricane.  Hurricane Franklin has about another 6 to 12 hours to strengthen.  Once Franklin makes landfall and moves into the mountains, the surface circulation will weaken quickly.

A subtropical ridge is steering Hurricane Franklin toward the west and that general motion is expected to continue.  Hurricanes often turn slightly south of west when the approach the coast of the southwestern Bay of Campeche.  On its anticipated track the center Hurricane Franklin could make landfall on the coast of Mexico north of Veracruz in less than 12 hours.  The most likely landfall would be between Veracruz and Nautla.

Hurricane Franklin will bring strong gusty winds, a storm surge and heavy rain at the coast.  The storm surge could reach 6 to 9 feet (2 to 3 meters) near and just to the north of where the center makes landfall.  Franklin could produce very heavy rain when it reaches the mountains and flash flooding is a serious risk.

Tropical Storm Franklin Moves Over Bay of Campeche and Strengthens

Tropical Storm Franklin moved off the Yucatan peninsula over the Bay of Campeche and began to strengthen on Tuesday night.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Franklin was located at latitude 20.3°N and longitude 91.3°W which put it about 325 miles (525 km) east-northeast of Veracruz, Mexico.  Franklin was moving toward the west-northwest at 10 m.p.h. (16 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 996 mb.

A Hurricane Warning was in effect for the portion of the coast from Puerto de Veracruz to Tuxpan, Mexico.  A Hurricane Watch was in effect for the portion of the coast from Tuxpan to Rio Panuco.  A Tropical Storm Waring was in effect for the portion of the coast from Celestun to Puerto de Veracruz and from Tuxpan to Rio Panuco.

Although Tropical Storm Franklin weakened as it moved across the Yucatan peninsula on Tuesday, its circulation maintained its structural integrity.  In fact, a tighter inner core developed at the center of the circulation while the tropical storm moved over land.  New thunderstorms began to form near the center of Tropical Storm Franklin as soon as the center moved back over water.  A primary band of thunderstorms began to wrap tightly around the eastern and northern sides of the center.  Additional bands of showers and thunderstorms began to form over the Bay of Campeche.  Thunderstorms in the core were generating upper level divergence which is pumping away mass.

Tropical Storm Franklin will move over an environment very favorable for intensification on Wednesday.  Franklin will move over water where the Sea Surface Temperature is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  An upper level trough over the Bahamas may enhance the upper divergence by creating an outflow channel to the east of Franklin.  Tropical Storm Franklin will intensify on Wednesday and there could be a period of rapid intensification.  Franklin is likely to become a hurricane.

Tropical Storm Franklin is being steered to the west by a subtropical high to its northeast.  A general westerly motion is expected to continue for another day or two.  On its anticipated track Tropical Storm Franklin will approach the coast of Mexico north of Veracruz on Wednesday night.  Franklin will bring gusty winds, heavy rain and a storm surge at the coast.  When Franklin moves inland the mountains will enhance the rising motion and very heavy rain could fall.  The heavy rain could cause flash floods.

Tropical Storm Franklin Makes Landfall on Yucatan

The center of Tropical Storm Franklin made landfall on the southeast coast of the Yucatan peninsula on Monday night.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Franklin was located at latitude 19.1°N and longitude 87.3°W which put it about 75 miles (120 km) east-northeast of Chetumal, Mexico.  Franklin was moving toward the west-northwest at 14 m.p.h. (22 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 995 mb.

A Hurricane Watch is in effect for the portion of the coast from Puerto de Veracruz to Rio Panuco, Mexico.  A Tropical Storm Warning is in effect for the portion of the coast from Chetumal to Sabancuy, Mexico and from Belize City northward to the Belize/Mexico border.  A Tropical Storm Watch is in effect for the portion of the coast from Sabancuy to Puerto de Veracruz, Mexico.

The circulation of Tropical Storm Franklin became better organized on Monday, but thunderstorms were unable to consolidate around the core of the circulation.  A ring of showers and weaker thunderstorms surrounds the center of circulation.  A band of stronger thunderstorms curls around the eastern side of the circulation.  The are weaker bands of showers and thunderstorms in the western half of the circulation.  The thunderstorms in the eastern side of Franklin were generating upper level divergence which was pumping mass away to the east of the tropical storm.

Tropical Storm Franklin will weaken as it moves over the Yucatan peninsula.  Franklin will spend approximately 18 hours over land and it will be a weaker tropical storm or tropical depression by the time it reaches the southern Gulf of Mexico.  The Sea Surface Temperature of the southern Gulf of Mexico is near 30°C.  The upper level winds should be weak and there is likely to be little vertical wind shear when Franklin moves over the southern Gulf.  Franklin is likely to intensify when it moves over the Gulf of Mexico and it could strengthen into a hurricane.

A subtropical high pressure system is steering Tropical Storm Franklin toward the west-northwest and that general motion is expected to continue for another day or two.  On its anticipated track Franklin will move across the Yucatan peninsula on Tuesday.  Franklin will produce gusty winds and locally heavy rainfall.  Floods could occur in some locations.