Tag Archives: 97L

Low Pressure System Forms Over Western Caribbean Sea

A low pressure system formed over the western Caribbean Sea on Sunday.  The U.S. National Hurricane Center designated the system as Invest 97L.  At 8:00 p.m. EDT on Sunday the center of Invest 97L was located at latitude 15.7°N and longitude 92.8°W which put the center about 425 miles (690 km) southeast of Cozmel, Mexico.  The low pressure system was moving toward the north-northwest at 5 m.p.h. (8 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 1006 mb.

A low pressure system formed over the western Caribbean Sea northeast of Cabo Gracias a Dios on Sunday.  Thunderstorms developed in the eastern side of the low pressure that was over the western Caribbean Sea.  Much of the western side of Invest 97L was over Honduras and Nicaragua.  Bands in the western side of the low pressure system consisted primarily of showers and lower clouds.

The low pressure system designated as Invest 97L will move through an environment favorable for the formation of a tropical cyclone during the next 24 hours.  Invest 97L The tropical depression will be over water where the Sea Surface Temperatures are near 30°C.  It will move under the middle of an upper level ridge over the western Caribbean Sea.  The upper level winds are weak near the middle of the ridge and there will be little vertical wind shear.  Invest 97L is likely to form into a tropical depression or a tropical storm on Monday.

A reconnaissance plane is tentatively scheduled to investigated the low pressure system on Monday afternoon, if necessary.

The low pressure system designated as Invest 97L will move around the western end of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Invest 97L toward the north-northwest during the next 24 hours.  On its anticipated track, the low pressure system will move over the northwestern Caribbean Sea on Monday.  Invest 97L is likely to move into the Gulf of Mexico by the middle of the week.

Tropical Wave Likely to Prompt Watches and Warnings for Florida

A tropical wave over eastern Cuba is likely to prompt the issuance of Tropical Storm Watches and Warnings for Florida on Friday.  The tropical wave is currently designated as Invest 97L.  At 2:00 a.m. EDT on Friday the center of Invest 97L was located at latitude 20.4°N and longitude 74.1°W which put the center about 80 miles (130 km) east of Guantanamo, Cuba.  The tropical wave was moving toward the west-northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1012 mb.

The axis of a tropical wave is over eastern Cuba early on Friday morning.  The tropical wave is currently designated as Invest 97L.  There is not a well defined low level circulation in the tropical wave.  There is a broad counterclockwise rotation along the axis of the tropical wave.  Much of the rotation is over eastern Cuba.  Clusters of showers and thunderstorms are embedded in the broad counterclockwise rotation.

The tropical wave currently designated as Invest 97L will move into an environment favorable for the formation of a tropical cyclone during the next 24 hours.  Invest 97L will move over water where the Sea Surface Temperatures are near 30°C.   It will move under the southeastern part of an upper level ridge over the southeastern U.S.  The ridge will produce northeasterly winds that will blow toward the top of the tropical wave.  The winds in the lower levels of the atmosphere will also blow from the east and there will be little vertical wind shear.  The tropical wave is unlikely to develop into a tropical cyclone as long as the center of the wave is over Cuba.  A tropical depression or a tropical storm is likely to form on Saturday when Invest 97L moves over the eastern Gulf of Mexico.

The tropical wave is moving around the southwestern part of a high pressure system over the western Atlantic Ocean.  The high pressure system will steer Invest 97L toward the west-northwest during the next 24 hours.  On its anticipated track, the tropical wave will move toward the Florida Keys.  Invest 97L is likely to move toward the north during the weekend when it reaches the western end of the high pressure system.

The tropical wave is likely to bring gusty winds and locally heavy rain to Florida during the weekend.  Heavy rain could cause widespread flooding.

Tropical Wave West of Africa Watched for Development

A tropical wave over the Atlantic Ocean west of Africa was being watched for development on Monday afternoon. The tropical wave was designated as Invest 97L on Monday. At 2:00 p.m. EDT on Monday the center of the tropical wave was located at latitude 11.7°N and longitude 22.7°W which put it about 230 miles (350 km) south of the Cabo Verde Islands. The tropical wave was moving toward the west at 19 m.p.h. (30 km/h). The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h). The minimum surface pressure was 1010 mb.

A tropical wave that moved over the Atlantic Ocean west of Africa during the weekend was being monitored for possible development of a tropical depression on Monday afternoon. The tropical wave exhibited a typical structure. There was no center of circulation evident in the lower levels of the atmosphere. There were linear bands of showers and thunderstorms that were moving with the tropical wave. Thunderstorms near the axis of the wave were generating upper level divergence that pumped mass away from the tropical wave.

The tropical wave will move through an environment favorable for the development of a tropical depression during the next several days. The tropical wave will move over water where the Sea Surface Temperatures are near 27˚C. It will move under the axis of an upper level ridge that extends from the west coast of Africa to the Caribbean Sea. The upper level winds are weak near the axis of the ridge. The tropical wave will move along the southern side of a subtropical pressure system over the Atlantic Ocean. The subtropical high is producing strong easterly winds in the lower level of the atmosphere. The strong low level winds may cause vertical wind shear in the lower levels of the atmosphere, which could inhibit the formation of a tropical depression. The National Hurricane Center is indicating that there is a probability of 40% of the formation of a tropical depression during the next five days.

The subtropical high pressure system will steer the tropical wave quickly toward the west-northwest during the next few days. On its anticipated track the tropical wave could approach the northern Leeward Islands in a few days. It could be a tropical depression or tropical storm by that time.

Invest 97L Poses Risk for Caribbean Sea

A tropical disturbance designated as Invest 97L poses a potential risk for locations around the Caribbean Sea.  At 8:00 p.m. EDT on Tuesday the center of Invest 97L was located at latitude 13.1°N and longitude 55.3°W which put it about 285 miles (460 km) east of Barbados.  Invest 97L was moving toward the west at 19 m.p.h. (31 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. (70 km/h).  The minimum surface pressure was 1008 mb.

A U.S. Air Force Reserve Hurricane Hunter aircraft flew a reconnaissance mission into Invest 97L on Tuesday afternoon.  The plane found the there were winds to near tropical storm force, but it could not identify a closed circulation.  The winds on the western side were weaker and the plane was unable to find a surface center.  There does seem to be cyclonic rotation above the surface at least on infrared satellite imagery.

The circulation in Invest 97L is still organizing.  Many of the stronger thunderstorms are forming north and east of the apparent center on satellite imagery.  Rainbands are also forming north and east of the center.  Recent satellite images suggest that some thunderstorms could be developing closer to the center of cyclonic rotation.  The current thunderstorms are generating upper level divergence which is pumping out mass to the north and east of the system.

Invest 97L is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 29°C.  The upper level winds over the majority of the circulation are relatively weak.  An upper level trough over the Caribbean Sea is generating vertical wind shear over the northern fringe of the circulation.  Invest 97L could become a tropical storm at any time.

A subtropical high pressure system to the north of Invest 97L is steering it toward the west and that general motion is expected to continue for another day or two.  On its anticipated track Invest 97L will move through the Windward Islands near Barbados, St. Lucia, Martinique, and Dominica on Wednesday.  It could bring gusty winds and locally heavy rain to those locations.

Possible Tropical Development

The National Hurricane Center (NHC) is monitoring two tropical disturbances which are designated Invest 96L and Invest 97L for possible development into tropical cyclones.

At 8:00 p.m. EDT on Thursday the center of Invest 97L was located at latitude 13.4°N and longitude 37.0°W which put it about 1525 miles (2460 km) east-southeast of the Leeward Islands.  Invest 97L was moving toward the west at 21 m.p.h. (34 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 1011 mb.

At 8:00 p.m. EDT on Thursday the center of Invest 96L was located at latitude 11.2°N and longitude 20.9°W which put it about 320 miles (515 km) south-southeast of the Cape Verde Islands.  Invest 96L was moving toward the west-northwest at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1010 mb.

Invest 97L consists of a fast moving tropical wave over the central Atlantic Ocean.  The circulation of Invest 97L is not well organized.  A few thunderstorms are occurring near the northern part of the axis of the tropical wave, but convection is scattered.  The rapid forward motion of the wave is preventing the thunderstorms from consolidating around a center of circulation.

If the forward speed of Invest 97L slows, then it may move into an environment that is more favorable for the development of a tropical cyclone.  It is over water where the Sea Surface Temperature (SST) is near 27°C and it will move over warmer water as it gets closer to the Caribbean Sea.  There is not much vertical wind shear except for the low level shear created by the rapid forward motion of the wave.  There is drier air to the north of Invest 97L, but it is embedded in the moister air closer to the Equator.  NHC has a 30% probability that Invest 97L will develop into a tropical cyclone during the next five days.  As a result, NHC has tentatively tasked a plane to fly reconnaissance into Invest 97L on Saturday if it shows signs of developing as it approaches the Caribbean Sea.

Invest 96L also consists of a tropical wave, but it is more well organized than Invest 97L  There are numerous thunderstorms west of the center of circulation and some rainbands are developing south of the center of circulation.  The thunderstorms west of the center are starting to generate some upper level divergence to the west of Invest 96L.  There are some indications that a low level center of circulation may be forming.

Invest 96L is currently in an environment that is mostly favorable for further development.  It is moving over water where the SSTs are near 28°C.  An upper level ridge north of Invest 96L is causing easterly winds to blow over the top of it.  The vertical wind shear is moderate and shear is the primary factor slowing the organization of the Invest 96L.  NHC has a 40% probability that Invest 96L will develop into a tropical cyclone during the next five days.

Because it is more well organized and it is moving more slowly, Invest 96L has a better chance for developing into a tropical cyclone during the next two days.  However, Invest 96L could move into a less favorable environment after that time.  Invest 97L will be moving into a more favorable environment during the weekend.  If Invest 97L holds together until its forward speed slows, then it could have a better chance of developing in several days.  If Invest 97L becomes a tropical cyclone it could threaten portions of the Caribbean Sea.