Tag Archives: Gulf of Mexico

Tropical Storm Beatriz Brings Heavy Rain to Southern Mexico

Tropical Depression Two-E intensified into Tropical Storm Beatriz on Thursday and Beatriz brought heavy rain to parts of southern Mexico.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Beatriz was located at latitude 15.5°N and longitude 96.8°W which put it about 25 miles (40 km) southwest of Puerto Angel, Mexico.  Beatriz was moving toward the north-northeast at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 45 m.p.h. (75 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1004 mb.  A Tropical Storm Warning was in effect for the portion of the coast from Salina Cruz to Puerto Escondido.

Tropical Depression Two-E intensified into Tropical Storm Beatriz on Thursday even though its structure evolved into a more asymmetrical system.  Tropical Storm Beatriz appeared to consist of a larger low pressure system which was centered just off the coast of Mexico.  The weather radar from Puerto Angel confirmed that the center of circulation was still offshore.  There were several smaller (mesoscale) counterclockwise rotating circulations that were revolving around the center of the larger low.  At least one of the smaller circulations was already over southern Mexico.  Many of the thunderstorms were occurring in a broad band that wrapped around the eastern and northern portions of the larger low pressure system.  The strongest winds were occurring within this primary rainband.  There were far fewer thunderstorms in the western half of the circulation.  It seemed that after air descended from mountains in Mexico then the air was drawn into the western side of Tropical Storm Beatriz.  The warmer drier air was inhibiting the formation of thunderstorms in the western half of Beatriz.

Although Tropical Storm Beatriz is over water where the Sea Surface Temperature is near 30°C, other environmental factors are unfavorable for intensification.  The proximity to land and the apparent ingestion of drier air are both negative factors.  A narrow upper level ridge oriented from the south-southwest to the north-northeast and a upper level trough to the west of Beatriz are producing brisk southerly winds that are blowing toward the top of the circulation.  Those upper level winds are causing moderate vertical wind shear.  Therefore, Tropical Storm Beatriz is unlike to intensify further during the next several days.

The future track of Tropical Storm Beatriz is uncertain.  If the circulation of Beatriz remains intact then the upper level trough and upper level ridge are likely to steer it toward the north-northeast.  Tropical Storm Beatriz would dissipate over the mountains of Mexico if that scenario occurs.  If the upper level winds are strong enough, the vertical shear could detach the upper portion of the circulation from the low level circulation.  That scenario sometimes occurs when slow moving storms approach the south coast of Mexico.  If that happens, the upper half of the circulation could be transported across Mexico and move over the southern Gulf of Mexico.  Some models are suggesting that a new surface low could form over the southern Gulf in several days, but the wind shear would have to decrease in order for that to occur.  The lower level circulation could be left behind near the coast of Mexico where it would drift slowly near the coast.

Tropical Storm Beatriz is bringing heavy rains to parts of southern Mexico and the heavy rain will continue to fall on Friday.  Locally heavy rain in the more mountainous portions of Oaxaca could create the potential for dangerous flash floods.

Tropical Depression One-E Forms South of Mexico

A low level center of circulation developed near the southern edge of thunderstorms near the coast of Mexico on Monday and the National Hurricane Center designated the system as Tropical Depression One-E.  At 5:00 p.m. EDT on Monday the center of Tropical Depression One-E (TD1E) was located at latitude 14.2°N and longitude 97.0°W which put it about 185 miles (295 km) southwest of Salina Cruz, Mexico.  TD1E was moving toward the northeast at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (70 km/h).  The minimum surface pressure was 1006 mb.  The government of Mexico issued a Tropical Storm Watch for the portion of the coast that extends from Puerto Escondido to Boca de Pijijiapan, Mexico.

Tropical Depression One-E is not a particularly well organized circulation.  A large upper level trough that extends from west of Mexico over the Gulf of Mexico is producing strong southwesterly winds that are blowing over the top of the depression.  The is the same upper level trough that is also causing the vertical wind shear over Tropical Storm Colin in the Gulf of Mexico.  As a result of the significant vertical wind shear, most of the strong thunderstorms are occurring north and east of the center of circulation.  The wind shear may be causing the tropical depression to be tilted toward the northeast with height.  The low level center of circulation is near the southern edge of the stronger thunderstorms.  The thunderstorms generating some upper level divergence to the east of the depression.

The environment around TD1E is only marginal for further intensification.  The depression is over water where the Sea Surface Temperature is near 31°C.  However, the vertical wind shear is forecast to continue and TD1E does not have much time to intensify before the center moves over land.  Little change in intensity is expected and only slight strengthening may occur before landfall.  TD1E is likely to weaken rapidly after landfall.  However, it will be interesting to see if the middle and upper part of the circulation make it to the Gulf of Mexico.

The upper level trough is expected to continue to steer TD1E toward the northeast.  On its anticipated track, the low level center is forecast to reach the coast of Mexico in 12 to 24 hours.  In cases like this when there is strong vertical wind shear near the coast of Mexico, the upper portion of the circulation sometimes gets separated from the lower level circulation.  In that case, the upper half of the circulation would continue northeast while the lower circulation either lingers near the coast or moves slowly inland and dissipates.

The primary risks from Tropical Depression One-E are locally heavy rain and flash flooding.

Tropical Storm Colin Forms Over Gulf of Mexico and Heads for Florida

A broad area of low pressure over the southern Gulf of Mexico became more organized on Sunday and a U.S. Air Force Reserve Hurricane Hunter reconnaissance aircraft found sustained winds of 40 m.p.h. (65 km/h).  As a result, the National Hurricane Center classified the system as Tropical Storm Colin.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Colin was located at latitude 23.6°N and longitude 87.8°W which put it about 450 miles (720 km) southwest of Tampa, Florida.  Colin was moving toward the north at 9 m.p.h. (15 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were wind gusts to 50 m.p.h. (80 km/h).  The minimum surface pressure was 1003 mb.

A Tropical Storm Warning has been issued for the portion of the coast from Indian Pass to Englewood, Florida.  A Tropical Storm Warning has also been issued for the East Coast from Sebastian Inlet, Florida to Altamaha Sound, Georgia.  A Tropical Storm Watch has been issued for the portion of the coast from Altamaha Sound, Georgia to South Santee River, South Carolina.

The circulation of Tropical Storm Colin is very asymmetrical.  The stronger winds and most of the thunderstorms are east of the center of circulation.  Some rotation in the middle levels in the primary band on the east side of Colin is apparent on satellite imagery.  Winds to tropical storm force are occurring up to 185 miles (295 km) from the center of circulation.  However, the winds are much weaker in the western half of the circulation.

The environment around Tropical Storm Colin is marginal for intensification.  Colin is moving over water where the Sea Surface Temperature is near 28°C to 29°C.  So, there is sufficient energy in the upper ocean to support intensification.  An upper level low near Texas and an upper level ridge east of Colin are combining to produce southwesterly winds that are blowing over the western half of the storm.  Those winds are causing strong vertical wind shear which is preventing the development of thunderstorms in that part of the storm.  Part of the upper level ridge is over the eastern half of the circulation.  The upper level winds are weaker there and there is less vertical wind shear, which is allowing strong thunderstorms to persist in that part of Colin.  The upper level ridge is also enhancing upper level divergence to the east of Tropical Storm Colin.  If a new center of circulation were to form closer to the upper level ridge, then more intensification would be possible.  Colin is likely to intensify somewhat on Monday.

The upper low and upper level ridge are also steering Tropical Storm Colin toward the north.  Those features are expected to turn Colin toward the northeast on Monday.  On its anticipated track Tropical Storm Colin will approach the coast of Florida between Tampa and Apalachicola on Monday evening.  However, if a new center of circulation develops farther east, Colin could make landfall farther south along the coast and earlier on Monday.

Heavy rainfall is the greatest risk with Tropical Storm Colin.  It is pulling very humid air from the Caribbean Sea northward over the eastern Gulf of Mexico.  Tropical Storm Colin could also generate a storm surge of 1-6 feet near where the center makes landfall.  The coast along the northeastern Gulf of Mexico is very susceptible to storm surges and water rises will occur in that area.  Wind damage is likely to be minimal, although power outages may occur.  Some tornadoes could be generated when Colin moves over land.  Locally heavy rain could also fall in portions of the Mid-Atlantic states as the circulation of Tropical Storm Colin interacts with a cold front.

Tropical Storm Colin was named on June 5, which is the earliest date on record on which the third Atlantic Tropical Storm has formed.  During the record setting year of 2005 Tropical Storm (later to become Hurricane) Cindy was named on July 5.

Disturbance Near Yucatan Could Develop Over Gulf of Mexico

A tropical disturbance over the northwestern Caribbean Sea near the Yucatan peninsula is moving northwest and it could develop into a tropical cyclone when it moves over the southern Gulf of Mexico.  The National Hurricane Center (NHC) has designated the disturbance as Invest 93L and NHC is putting the probability of development into a tropical cyclone during the next two days at 80%.  At 8:00 p.m. EDT the center of Invest 93L was located at latitude 18.5°N and longitude 87.5°W which put it about 170 miles (270 km) south of Cancun, Mexico.  Invest 93L was moving toward the northwest at 11 m.p.h. (17 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 1005 mb.

Invest 93L consists of a broad area of low pressure at the surface.  Several bands of thunderstorms are occurring in the eastern and northern parts of the circulation.  There is no well defined center of circulation and there are fewer thunderstorms in the inner portion of the circulation.  The strongest winds are occurring in the bands of thunderstorms north and east of the center.  There is some upper level divergence to the east of Invest 93L.

The environment around Invest 93L is not totally favorable for development.  The Sea Surface Temperature in northwest Caribbean Sea is near 30°C, which means there is plenty of energy in the upper ocean.  However, an upper level low near Texas and an upper level ridge east of Invest 93L are combining to generate strong southwesterly winds that are blowing over the top of the disturbance.  Those winds are creating significant vertical wind shear which is inhibiting the development of Invest 93L.  The upper level ridge is enhancing the upper level divergence to the east of the disturbance which allowed the pressure to fall several millibars on Saturday.  The upper winds are lighter near the axis of the ridge which is why the stronger bands of thunderstorms are persisting in that area.

Invest 93L is forecast to move toward the Yucatan peninsula on Sunday.  If the broad area over low pressure moves over land that will prevent it from developing until it moves back over water.  Numerical models are guiding that the disturbance will develop into a tropical cyclone when the area of low pressure moves over the southern Gulf of Mexico.  The upper level ridge is forecast to extend over the southeastern Gulf and if that happens the wind shear could decrease enough to allow development to occur.  Invest 93L could become a tropical depression or a tropical storm over the Gulf of Mexico.

The southwesterly flow over the Gulf of Mexico is forecast to turn Invest 93L toward the northeast.  On its anticipated track the system could reach the west coast of Florida near Cedar Key late Monday or early Tuesday.  The primary risk is likely to be locally heavy rain.  However, the coast in that area is very susceptible to storm surge and there could be some rise in the water level.  The National Hurricane Center has tentatively tasked a reconnaissance plane to investigate Invest 93L on Sunday, if necessary.

Disturbance Brings Squally Weather to the Northwest Caribbean Sea

A complicated disturbance over the northwestern Caribbean Sea is bringing squally weather to that area.  A tropical wave over the western Caribbean Sea is interacting with an upper level low over eastern Mexico.  The disturbance is causing thunderstorms over a region that extends from the northwestern Caribbean Sea to the southern Gulf of Mexico.  Upper level divergence east of the upper low has led to the formation of a surface low pressure system east of Belize.  At 7:00 p.m. EST on Thursday the center of the surface low was located at latitude 18°N and longitude 86°W which put it about 150 miles (240 km) east-southeast of Chetumal, Mexico.  The surface low was moving toward the west-northwest at 10 m.p.h. (16 m.p.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 1011 mb.

The disturbance is not very well organized, which is normally the case when a tropical wave interacts with an upper level low.  There is a broken area of thunderstorms that extends around the east and northern sides of the disturbance.  However, there are not many thunderstorms close to the center of the surface low.  The upper low is causing vertical wind shear over the western half of the surface low.  Some upper level divergence is occurring over the eastern half of the surface low.

A large high pressure system over the western Atlantic Ocean is steering the disturbance toward the west-northwest.  That general steering pattern is expected to continue for the next two days.  On its anticipated track the disturbance will move over the Yucatan peninsula and over the southern Gulf of Mexico during the next several days.

The disturbance is in an environment that is marginally favorable for tropical development.  The Sea Surface Temperature of the northwestern Caribbean is near 29°C.  There is vertical wind shear, but it may be just small enough to allow for slow development.  On the other hand, the disturbance will move over the Yucatan peninsula which will further inhibit development.  There may also be a chance for development after the disturbance moves over the southern Gulf of Mexico.  The National Hurricane Center is giving a 20% probability of tropical cyclone formation out of the disturbance.

Tropical Storm Bill Moving Farther Into Texas

Tropical Storm Bill continued to move farther into Texas after making landfall near Matagorda Island on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Bill was located at latitude 29.5°N and longitude 97.0°W which put it about 45 miles (70 km) north of Victoria, Texas.  Bill was moving toward the north at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 40 m.p.h. (65 km/h) and there were winds gusts to 50 m.p.h. (85 km/h).  The minimum surface pressure was 1000 mb.  The strongest winds were occurring primarily in a rainband over the Gulf of Mexico.  A Tropical Storm Warning was in effect for the portion of the coast from Port Oconnor to San Luis Pass, Texas.

The circulation around Bill remains well organized and most of the rain is falling north and east of the center.  The circulation will slowly spin down as it moves farther away from the Gulf of Mexico and its supply of moist air is reduced.  Bill is expected to move north and then turn northeast as it moves around the western end of a high pressure system centered off the coast of the southeastern U.S.  The greatest risk will be from locally heavy rain falling on saturated ground in north Texas and Oklahoma.  Flooding may occur in some locations as a result of the heavy rain.  Some of the moisture associated with the tropical storm could be transported over the Ohio River Valley later this week.

Tropical Storm Bills Forms Near Texas

The National Hurricane Center (NHC) classified a low pressure system over the western Gulf of Mexico as Tropical Storm Bill.  At 11:00 p.m. EDT on Monday the center of Tropical Storm Bill was located at latitude 27.1°N and longitude 94.2°W which put it about 160 miles (260 km) east-southeast of Port OConnor, Texas and about 155 miles (250 km) south-southeast of Galveston, Texas.  Bill was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 50 m.p.h. (85 km/h) and there were wind gusts to 65 m.p.h. (105 km/h).  The minimum surface pressure was 1005 mb.  A Tropical Storm Warning has been issued for the portion of the coast from Baffin Bay to High Island, Texas.

Bill formed as a result of the interaction between a broad surface low pressure system and an upper level low over the Gulf of Mexico.  Thunderstorms began to form near the center of circulation on Monday afternoon and the structure of the system changed to a more tropical cyclone like pattern.  The thunderstorms near the center began to warm the middle and upper troposphere and create a warm core.  The thunderstorms became substantial enough to generate upper level divergence from the core of the circulation and NHC classified it as Tropical Storm Bill.  Bill is moving over water where the Sea Surface Temperature (SST) is near 29°C.  The vertical wind shear over the system decreased on Monday and Bill has a few hours during which it could intensify before it makes landfall in Texas.

An upper level ridge over the southeastern U.S. is steering Bill northwestward toward the coast of Texas and that motion is expected to continue.  Bill is expected to make landfall in Texas on Tuesday.  Although Bill will bring some wind when it makes landfall, heavy rainfall will be the biggest hazard.  Heavy rain on top of wet soils will create the potential for new flooding in some locations, especially in Texas and Oklahoma.  Winds blowing toward the coast will also create some water level rises and Coastal Flood Warnings and Advisories have been issued for portions of the coast of Texas and Louisiana.

Low Pressure Organizing Over the Southern Gulf of Mexico

A complex low pressure system over the southern Gulf of Mexico is showing signs of greater organization.  A reconnaissance aircraft investigated the system on Sunday afternoon and found evidence of a broad area of low pressure at the surface and winds to tropical storm force northeast of the low.  The official designation for this system is Invest 91L.  At 11:00 p.m. EDT on Sunday night the approximate center of the broad low was located at latitude 22.7°N and longitude 90.2°W which put it about 540 miles (870 km) south-southeast of Galveston, Texas and about 540 miles (870 km) east-southeast of Brownsville, Texas.  The low was moving toward the northwest at 14 m.p.h. (23 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 1007 mb.

Invest 91L is a complex system which includes an upper level low over the southern Gulf of Mexico and a broad area of low pressure at the surface.  Clusters of thunderstorms are forming intermittently east and north of the center of circulation.  The pressure gradient between a strong high pressure system centered over the Atlantic Ocean and the developing surface low is causing the strongest winds to be found in the northeastern part of Invest 91L.  The upper level low is causing the system is to exhibit a more subtropical mode of formation rather a typical tropical genesis.  However, more thunderstorms are beginning to develop closer to the center of circulation and the National Hurricane Center is giving Invest 91L an 80% chance of becoming a tropical cyclone.  The low is moving over water where the Sea Surface Temperature (SST) is around 27°C to 28°C, which is warm enough to support the development of a tropical cyclone.  The upper level low was generating vertical wind shear, but if the surface low develops under the center of the upper low, then the wind shear will have less of an effect.  If more thunderstorms form near the center of circulation and a warm core develops, then the low could be classified as a tropical storm on Monday.  Some intensification is possible because of the warm SSTs.

An upper level ridge centered over the southeastern U.S. is expected to steer the system toward the northwest and it could make landfall on the coast of Texas in 24 to 48 hours.  The primary risk will be locally heavy rainfall, although a minor storm surge could occur in some coastal locations.

Possible Tropical Development in Western Gulf of Mexico

An area of showers and thunderstorms near the Yucatan Peninsula has shown signs of a cyclonic circulation, although the rotation may be in the middle troposphere and not at the surface.  The formal designation of this system is Invest 91L.  At 2:00 p.m EDT on Saturday the center of Invest 91L was located at latitude 20.0°N and longitude 88.4°W which put it about 100 miles (165 km) southeast of Merida, Mexico and about 760 miles (1220 km) south-southeast of Galveston, Texas.  Invest 91L was moving toward the northwest at 5 m.p.h. (8 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 1009 mb.  The National Hurricane Center is now giving Invest 91L a 50% chance of developing into a tropical depression or tropical storm in the next five days.  An additional reconnaissance plane has been scheduled to investigate it on Sunday afternoon.

The circulation of Invest 91L is not very well organized.  Almost all of the showers and thunderstorms are occurring in the eastern half of the circulation.  Visible satellite images indicate a possible center of cyclonic rotation over the Yucatan peninsula, but it is not clear if the rotation extends all of the way down to the surface.  Counterclockwise winds around an upper level low over the Gulf of Mexico are generating significant vertical wind shear over Invest 91L.  However, the upper level winds east of the upper low are diverging, which is enhancing rising motion and is supporting the development of the showers and thunderstorms in that area.  The upper level divergence is also causing the surface pressure to decrease slowly, which could lead to the formation of a surface center of low pressure.

When Invest 91L moves into the southern Gulf of Mexico, it will move over water where the Sea Surface Temperature is near 27°C to 28°C.  So, there is sufficient energy in the upper ocean to support the development of a tropical cyclone.  The key factor will be the interaction between the upper low and any surface center that forms.  If the surface center forms too close to the upper low, then vertical wind shear will likely inhibit development and the system will remain fairly weak.  If the surface low develops a little farther southeast of the upper low, then there will be less shear and more upper level divergence.  That could allow for more intensification.

Invest 91L is expected to move with the upper low as the upper low moves northward.  Most guidance from numerical models moves the system toward the north-northwest toward the Upper Texas Coast.  However, there will be above normal uncertainty in the track until a well defined center of circulation forms at the surface.

Interests in the western Gulf of Mexico should monitor the progress of Invest 91L.

TD 5 becomes Tropical Storm Dolly

Tropical Depression Five intensified into Tropical Storm Dolly during the overnight hours.  An Air Force Reserve Hurricane Hunter reconnaissance aircraft found that the maximum sustained wind speeds around Tropical Depression Five had increased to tropical storm force and the National Hurricane Center upgraded the system to Tropical Storm Dolly.  The plane also found that a new center of circulation had developed farther to the north of the previous center and the government of Mexico extended the Tropical Storm Warning northward to Barra El Mezquital.

At 8:00 a.m. EDT on Tuesday the center of Tropical Storm Dolly was located at latitude 23.0°N and longitude 95.7°W which put it about 145 miles east-southeast of La Pesca, Mexico and about 220 miles south-southeast of Brownsville, Texas.  Dolly was moving toward the west-northwest at 13 m.p.h.  The maximum sustained wind speed was 50 m.p.h. and the minimum surface pressure was 1005 mb.  A Tropical Storm Warning is in effect from Tuxpan to Barra El Mezquital, Mexico.

Dolly is expected to continue to move toward the west-northwest and it could make landfall in northern Mexico later today.  The Sea Surface Temperatures in the western Gulf of Mexico are very warm and some further intensification is likely.   Locally heavy rains are possible after Dolly makes landfall.