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Major Hurricane Roslyn Nears West Coast of Mexico

Major Hurricane Roslyn neared the west coast of Mexico on Saturday night. At 11:00 p.m. EDT on Saturday the center of Hurricane Roslyn was located at latitude 20.0°N and longitude 106.6°W which put it about 65 miles (105 km) west-southwest of Cabo Corrientes, Mexico. Roslyn was moving toward the north at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 954 mb.

A Hurricane Warning was in effect for Las Islas Marias. A Hurricane Warning was also in effect for the portion of the coast from Playa Perula to Escuinapa, Mexico. The Hurricane Warning included Puerto Vallarta. A Hurricane Watch was in effect for the portion of the coast from Escuinapa to Mazatlan, Mexico. Tropical Storm Warnings were in effect for the portions of the coast from Manzanillo to Playa Perula, Mexico and from Escuinapa to Mazatlan, Mexico.

Hurricane Roslyn was at Category 4 intensity on the Saffir-Simpson Scale as it approached the west coast of Mexico on Saturday night. A circular eye with a diameter of 10 miles (16 km) was at the center of Roslyn’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Roslyn. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Roslyn was small. Winds to hurricane force extended out 30 miles (50 km) from the center of Roslyn’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 8.5 and the Hurricane Wind Intensity Size Index (HWISI) was 33.6. Hurricane Roslyn was capable of causing localized severe damage.

Hurricane Roslyn will into an environment that will become unfavorable for intensification during the next few hours. Roslyn will move over water where the Sea Surface Temperatures are near 29˚C. However, an upper level trough west of Baja California will produce southwesterly winds that will blow toward the top of Roslyn’s circulation. Those winds will cause the vertical wind shear to increase. Hurricane Roslyn could start to weaken when the wind shear increases.

The upper level trough west of Baja California will steer Hurricane Roslyn toward the northeast during Sunday. On its anticipated track Hurricane Roslyn will make landfall on the west coast of Mexico near San Blas on Sunday morning. Although Roslyn could weaken before it makes landfall, it is likely to still be a major hurricane when it reaches the west coast of Mexico. Roslyn will bring strong gusty winds and locally heavy rain to Nayarit. Heavy rain could cause flash floods in some locations. Hurricane Roslyn could cause a storm surge of up to 13 feet (4 meters) along the coast. Hurricane Roslyn will be capable of causing localized major damage.

Roslyn Rapidly Intensifies to a Major Hurricane

Hurricane Roslyn rapidly intensified to a major hurricane over the Eastern North Pacific Ocean near the west coast of Mexico during Friday night. At 8:00 a.m. EDT on Saturday the center of Hurricane Roslyn was located at latitude 17.6°N and longitude 106.3°W which put it about 200 miles (320 km) south-southwest of Cabo Corrientes, Mexico. Roslyn was moving toward the northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 960 mb.

A Hurricane Warning was in effect for Las Islas Marias. A Hurricane Warning was also in effect for the portion of the coast from Playa Perula to El Roblito, Mexico. The Hurricane Warning included Puerto Vallarta. A Hurricane Watch was in effect for the portion of the coast from El Roblito to Mazatlan, Mexico. Tropical Storm Warnings were in effect for the portions of the coast from Manzanillo to Playa Perula, Mexico and from El Roblito to Mazatlan, Mexico.

Hurricane Roslyn rapidly intensified to a major hurricane during Friday night. A circular eye with a diameter of 12 miles (19 km) was at the center of Roslyn’s circulation. The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Roslyn. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Roslyn was small. Winds to hurricane force extended out 25 miles (40 km) from the center of Roslyn’s circulation. Winds to tropical storm force extended out 80 miles from the center of circulation. The Hurricane Intensity Index (HII) was 22.1. The Hurricane Size Index (HSI) was 7.0 and the Hurricane Wind Intensity Size Index (HWISI) was 29.1. Hurricane Roslyn was capable of causing localized major damage.

Hurricane Roslyn will move through an environment favorable for intensification during the next 12 hours. Roslyn will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis on an upper level ridge over the Eastern North Pacific. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Hurricane Roslyn is likely to intensify during the next 12 hours. Roslyn could intensify rapidly for a few more hours. Hurricane Roslyn could strengthen to a Category 4 hurricane on the Saffir-Simpson Scale. An upper level trough west of Baja California will produce southwesterly winds on Saturday night that will blow toward the top of Roslyn’s circulation. Those winds will cause the wind shear to increase. Hurricane Roslyn could start to weaken when the wind shear increases.

Hurricane Roslyn will move around the western side of a surface high pressure system centered over northern Mexico during the next 12 hours. The high pressure system will steer Roslyn toward the north. The upper level trough west of Baja California will steer Hurricane Roslyn toward the northeast on Saturday night and Sunday. The center of Roslyn is likely to pass just to the west of Cabo Corrientes during Friday night. On its anticipated track Hurricane Roslyn could make landfall on the west coast of Mexico near San Blas on Sunday morning. Roslyn will bring strong gusty winds and locally heavy rain to Nayarit. Heavy rain could cause flash floods in some locations. Hurricane Roslyn could cause a storm surge of up to 13 feet (4 meters) along the coast. Hurricane Roslyn will be capable of causing localized major damage.

Roslyn Intensifies to a Hurricane; Mexico Issues Warnings

Former Tropical Storm Roslyn intensified to a hurricane over the Eastern North Pacific Ocean on Friday night and the government of Mexico issued Hurricane Warnings and Tropical Storm Warnings for portions of the coast. At 11:00 p.m. EDT on Friday the center of Hurricane Roslyn was located at latitude 16.7°N and longitude 105.6°W which put it about 255 miles (410 km) south of Cabo Corrientes, Mexico. Roslyn was moving toward the west-northwest at 7 m.p.h. (11 km/h). The maximum sustained wind speed was 85 m.p.h. (135 km/h) and there were wind gusts to 100 m.p.h. (160 km/h). The minimum surface pressure was 982 mb.

A Hurricane Warning was in effect for Las Islas Marias. A Hurricane Warning was also in effect for the portion of the coast from Playa Perula to El Roblito, Mexico. The Hurricane Warning included Puerto Vallarta. A Hurricane Watch was in effect for the portion of the coast from El Roblito to Mazatlan, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Manzanillo to Playa Perula, Mexico.

Former Tropical Storm Roslyn intensified to a hurricane on Friday night near the west coast of Mexico. A small circular eye formed at the center of Hurricane Roslyn’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Roslyn. Storm near the core generated upper level divergence that pumped mass away from the hurricane. The circulation around Hurricane Roslyn was small. Winds to hurricane force extended out 20 miles on the norther side of Roslyn’s circulation. Winds to tropical storm force extended out 70 miles from the center of circulation.

Hurricane Roslyn will move through an environment favorable for intensification during the next 24 hours. Roslyn will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis on an upper level ridge over the Eastern North Pacific. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Hurricane Roslyn will intensify during the next 24 hours. Roslyn could intensify rapidly at times. Hurricane Roslyn could strengthen to a major hurricane.

Hurricane Roslyn will move around the western side of a surface high pressure system centered over northern Mexico on Saturday. The high pressure system will steer Roslyn toward the north on Saturday. An upper level trough west of Baja California will steer Hurricane Roslyn toward the northeast on Saturday night and Sunday. On its anticipated track Hurricane Roslyn could make landfall on the west coast of Mexico near San Blas on Sunday morning. Roslyn will bring strong gusty winds and locally heavy rain to the coast. Heavy rain could cause flash floods in some locations.

Tropical Depression 19E Strengthens to Tropical Storm Roslyn

Former Tropical Depression Nineteen-E strengthened to Tropical Storm Roslyn over the Eastern North Pacific Ocean south of Mexico on Thursday afternoon. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Roslyn was located at latitude 15.5°N and longitude 103.0°W which put it about 180 miles (295 km) south-southwest of Zihuatanejo, Mexico. Roslyn was moving toward the west at 7 m.p.h. (11 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.

The government of Mexico issued a Tropical Storm Watch for the portion of the coast from Manzanillo to Cabo Corrientes.

Tropical Storm Roslyn strengthened gradually on Thursday afternoon. The inner end of a rainband wrapped around the eastern side of the center of Roslyn’s circulation. Other bands of showers and thunderstorms were in the eastern half of Tropical Storm Roslyn. Bands in the western half of the circulation consisted primarily of showers and lower clouds. Storms near the center of Roslyn generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 60 miles (95 km) in the northeastern quadrant of Roslyn. The winds in the other parts of Roslyn’s circulation were blowing at less than tropical storm force.

Tropical Storm Roslyn will move through an environment favorable for intensification during the next 48 hours. Roslyn will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis on an upper level ridge over the Eastern North Pacific. The upper level winds are weak near the axis of the ridge and there will be little vertical wind shear. Tropical Storm Roslyn will strengthen during the next 48 hours. Roslyn could intensify to a hurricane by Friday night.

Tropical Storm Roslyn will move around the southwestern side of a surface high pressure system centered over northern Mexico. The high pressure system will steer Roslyn toward the west-northwest during the next 24 hours. On its anticipated track Tropical Storm Roslyn will move parallel to the southwest coast of Mexico during Friday. Roslyn will turn more toward the north when it reaches the western end of the high pressure system during the weekend. Roslyn could be west of Cabo Corrientes on Saturday night.

Tropical Depression Nineteen-E Forms South of Mexico

Tropical Depression Nineteen-E formed over the Eastern North Pacific Ocean south of Mexico on Wednesday night. At 11:00 p.m. EDT on Wednesday the center of Tropical Depression Nineteen-E was located at latitude 15.2°N and longitude 101.3°W which put it about 175 miles (280 km) south of Zihuatanejo, Mexico. The tropical depression was moving toward the west-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. (75 km/h). The minimum surface pressure was 1007 mb.

A low pressure system over the Eastern North Pacific Ocean south of Mexico strengthened on Wednesday night and the National Hurricane Center designated the system as Tropical Depression Nineteen-E. More thunderstorms were developing near the center of Tropical Depression Nineteen-E. Bands of showers and thunderstorms were revolving around the center of circulation. Storms near the center generated upper level divergence that pumped mass away from the tropical depression.

Tropical Depression Nineteen-E will move through an environment favorable for intensification during the next 48 hours. The tropical depression will move over water where the Sea Surface Temperatures are near 29˚C. It will move under the axis on an upper level ridge over the Eastern North Pacific. The upper level winds are weak and there will be little vertical wind shear. Tropical Depression Nineteen-E will strengthen during the next 48 hours. It could intensify to a tropical storm during the next 12 hours. It could strengthen to a hurricane by Friday evening.

Tropical Depression Nineteen-E will move around the southwestern side of a surface high pressure system centered over northern Mexico. The high pressure system will steer the tropical depression toward the west-northwest during the next 48 hours. On its anticipated track Tropical Depression Nineteen-E will move parallel to the southwest coast of Mexico. It will turn more toward the north when it reaches the western end of the high pressure system during the weekend.

Tropical Storms Sandra and Terry Develop over East Pacific

Tropical Storms Sandra and Terry developed over the Eastern North Pacific Ocean on Sunday afternoon. At 4:00 p.m. EST on Sunday the center of Tropical Storm Sandra was located at latitude 14.0°N and longitude 115.2°W which put it about 705 miles (1135 km) south-southwest of the southern tip of Baja California. Sandra was moving toward the west-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 wind gusts to 50 m.p.h. (80 km/h). The minimum surface pressure was 1006 mb.

At 4:00 p.m. EST on Sunday the center of Tropical Storm Terry was located at latitude 8.5°N and longitude 102.6°W which put it about 735 miles (1180 km) south of Manzanillo, Mexico. Terry was moving toward the west 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 1007 mb.

Based on data from a scatterometer on a satellite, the National Hurricane Center upgraded former Tropical Depression Nineteen-E to Tropical Storm Sandra on Sunday afternoon. It appeared from later satellite images that Tropical Storm Sandra might already be weakening. A large upper level trough approaching the west coast of the U.S. was producing strong southerly winds that were blowing across the top of Sandra’s circulation. Those winds were causing moderate vertical wind shear. The strong upper level winds blew the tops off thunderstorms near the center of Sandra. The strongest remaining thunderstorms were occurring in bands east of the center. Bands in other parts of Tropical Storm Sandra consisted primarily of showers and lower clouds. The strongest winds were in the eastern half of Sandra. Winds to tropical storm force extended out 90 miles in the eastern half of Sandra. The winds in the western half of the circulation were blowing at less than tropical storm force.

Tropical Storm Sandra will move through an environment mostly unfavorable for intensification during the next several days. Sandra will move over water where the Sea Surface Temperatures are near 27˚C. However, the large upper level trough will continue to produce strong vertical wind shear. The wind shear is likely to prevent Tropical Storm Sandra from strengthening. The strong shear could blow the top off of Sandra’s circulation and Tropical Storm Sandra is more likely to weaken during the next several days. Sandra will move south of a surface high pressure system over the Eastern North Pacific Ocean. The high pressure system will steer Sandra toward the west. On its anticipated track Tropical Storm Sandra will move farther away from Mexico.

More thunderstorms developed near the center of former Tropical Depression Eighteen-E on Sunday afternoon and the National Hurricane Center upgraded the system to Tropical Storm Terry. The circulation around Tropical Storm Terry exhibited more organization on satellite images. More thunderstorms also formed in bands revolving around the center of Terry. Storms near the center generated upper level divergence that pumped mass away from the tropical storm. Winds to tropical storm force extended out 60 miles (95 km) on the eastern side of Terry’s circulation. The winds in the western half of Terry were blowing at less than tropical storm force.

Tropical Storm Terry will move through an environment somewhat favorable for intensification during the next 24 hours. Terry will move over water where the Sea Surface Temperatures are near 28˚C. It will move through a region where the upper level wind are weak and there will be little vertical wind shear. Tropical Storm Terry could slowly intensify during the next 24 hours.

Tropical Storm Terry will move around the southern side of a surface high pressure system over the Eastern North Pacific Ocean. The high will steer Terry toward the west during the next few days. On its anticipated track Tropical Storm Terry will move farther away from Mexico.

Norbert Regains Tropical Depression Status South of Baja California

Former Tropical Storm Norbert regained tropical depression status south of Baja California on Tuesday afternoon.  At 5:00 p.m. EDT on Tuesday the center of Tropical Depression Norbert was located at latitude 19.8°N and longitude 111.7°W which put it about 245 miles (390 km) south-southwest of the southern tip of Baja California.  Norbert was moving toward the 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 wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1007 mb.

After strong vertical wind shear weakened former Tropical Storm Norbert on Saturday, the lower levels of the circulation drifted slowly toward the northwest.  The surface circulation around the former tropical storm moved into a region where the upper level winds were not as strong on Monday.  More thunderstorms began to develop in bands revolving around around the center of the surface circulation.  Additional thunderstorms formed near the center of the low on Tuesday afternoon and the National Hurricane Center designated the system as Tropical Depression Norbert.

Tropical Depression Norbert will move through a region somewhat favorable for intensification during the next 12 to 24 hours.  Norbert will move over water where the Sea Surface Temperature is near 28°C during the next 12 hours.  It will remain over water warmer than 26°C until Wednesday afternoon.  After that time Norbert will start to move over even cooler water.  An upper level low west of central Baja California will produce southerly winds which will blow toward the top of Tropical Depression Norbert.  Those winds will produce vertical wind shear, but Norbert will remain east of the strongest shear for another 24 hours.  When Norbert gets closer to the upper level low later on Wednesday, then the shear will increase and will cause it to weaken.

Tropical Depression Norbert will move between the upper level low west of Baja Californa and and upper level ridge over the southwestern U.S. and northern Mexico.  Those two weather systems will steer Norbert toward the northwest during the next several days.  On its anticipated track Tropical Depression Norbert is forecast to move parallel to the west coast of Baja California.

Tropical Storm Norbert Develops Southwest of Mexico

Tropical Storm Norbert developed southwest of Mexico on Tuesday morning.  At 5: 00 a.m. EDT on Tuesday the center of Tropical Storm Norbert was located at latitude 13.7°N and longitude 106.2°W which put it about 385 miles (625 km) south-southwest of Manzanillo, Mexico.  Norbert was moving toward the northwest at 7 m.p.h. (11 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 1002 mb.

The wind speed increased around a low pressure system southwest of Mexico on Tuesday morning and the National Hurricane Center designated the system as Tropical Storm Norbert.  More thunderstorms formed near the center of Norbert.  Storms near the center of circulation started to generate upper level divergence which pumped mass away to the northeast of the tropical storm.  Bands of showers and thunderstorms were developing outside the center of Norbert.  The circulation around Tropical Storm Norbert was small.  Winds to tropical storm force extended out 25 miles from the center of circulation.

Tropical Storm Norbert will be in an environment that is somewhat favorable for intensification.  Norbert will move over water where the Sea Surface Temperature is near 29°C.  A large upper level trough extends from northern Mexico over the Eastern North Pacific Ocean.  The trough will produce southwesterly winds which will blow toward the top of Tropical Storm Norbert.  Those winds will cause vertical wind shear and the shear will inhibit intensification.  Tropical Storm Norbert could strengthen if the shear is not too strong.

Tropical Storm Norbert will be in a region where the steering currents are weak..  Norbert is not likely to move very much during the next several days.  If Tropical Storm Norbert remains in the same location for more than a day, its winds will mix cooler water to the surface.  That would limit the energy Norbert could extract from the ocean, and the tropical storm could weaken.

Elsewhere over the Eastern North Pacific, Tropical Storm Marie continued to churn west away from Baja California.  At 5:00 a.m. EDT on Tuesday the center of Tropical Storm Marie was located at latitude 21.7°W and longitude 134.3°W which put it about 1560 miles (2510 km) west of the southern tip of Baja California.  Marie was moving toward the west-northwest at 9 m.p.h. (15 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 1003 mb.

Tropical Storm Priscilla Develops Near West Coast of Mexico

Tropical Storm Priscilla developed near the west coast of Mexico on Sunday.  At 2:00 p.m. EDT on Sunday the center of Tropical Storm Priscilla was located at latitude 18.6°N and longitude 104.0°W which put it about 55 miles (90 km) southeast of Manzanillo, Mexico.  Priscilla was moving toward the north at 10 m.p.h. (16 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.

A Tropical Storm Warning was in effect for the portion of the coast from Punta San Telmo to Playa Perula, Mexico.

A distinct low level center of circulation formed within a cluster of thunderstorms near the west coast of Mexico on Sunday and the National Hurricane Center designated the system as Tropical Storm Priscilla.  Thunderstorms were forming near the center of circulation.  Bands of showers and thunderstorms were also developing and the bands were revolving around the center of Priscilla.  Storms near the center were generating upper level divergence which was pumping mass away to the north of the tropical storm.  The circulation around Priscilla was small.  Winds to tropical storm force extended out 35 miles (55 km) from the center of circulation.

Tropical Storm Priscilla will move through an environment favorable for intensification during the next few hours.  The center of Priscilla will be over water where the Sea Surface Temperature is near 29°C.  It will be in a region where the upper level winds are not too strong and there will not be a lot of vertical wind shear.  However, the center of Tropical Storm Priscilla will be very close to Mexico.  The circulation around Priscilla will begin to pull drier air from over the land into the tropical storm.  Tropical Storm Priscilla could strengthen during the next few hours, but it is likely to weaken quickly when the center moves over Mexico.

Tropical Storm Priscilla will move around the western end of a high pressure system over Mexico.  The high will steer Priscilla on a track that will be a little to the west of straight north.  On its anticipated track, the center of Tropical Storm Priscilla will make landfall on the west coast of Mexico between Tecoman and Manzanillo within a few hours.  Priscilla could drop locally heavy rain which could cause flash floods in some places.

Tropical Depression Forms Over Gulf of California

Tropical Depression Nineteen-E formed over the Gulf of California on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Nineteen-E was located at latitude 26.3°N and longitude 110.9°W which put it about 35 miles (55 km) northeast of Loreto, Mexico.  It was moving toward the north at 13 m.p.h. (20 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 1004 mb.

The circulation of Tropical Depression Nineteen-E was still organizing .  There was a cluster of thunderstorms near the center of circulation.  Most of the stronger storms were east of the center.  Several short bands of showers and thunderstorms were beginning to develop north and south of the center of circulation.  Storms near the center were generating some upper level divergence which was pumping mass away to the northeast of the depression.

Tropical Depression Nineteen-E will move through an environment somewhat favorable for intensification during the next 12 hours.  The water in the Gulf of California is very warm and the depression will move over water where the Sea Surface Temperature is near 31°C.  An upper level trough west of California will produce southwesterly winds which will cause moderate vertical wind shear.  Tropical Depression Nineteen-E could intensify during the next 12 hours and it has a chance to become a tropical storm.

The upper level trough west of California will steer Tropical Depression Nineteen-E toward the north-northeast.  On its anticipated track the depression will reach the west coast of Mexico near Guaymas in about 12 hours.  It could be a tropical storm when it reaches the coast.  It will bring some gusty winds, but locally heavy rain is the greatest risk.  There is the potential for flash floods in parts of Sinaloa, Sonora and Chihuahua.  The lower portion of Tropical Depression Nineteen will weaken quickly after it makes landfall and moves over mountains in western Mexico.  The upper portion of the circulation and some of the moist air will be transported farther northeast and the remnants of the circulation could enhance rainfall farther inland.