Tag Archives: EP15

Tropical Storm Norma Drifts Near Baja California, Otis Rapidly Intensifies to Cat. 2 Hurricane

Tropical Storm Norma drifted near Baja California on Sunday, while Hurricane Otis rapidly strengthened into a Category 2 hurricane on the Saffir-Simpson Scale.  At 8:00 p.m. EDT on Sunday the center of Tropical Storm Norma was located at latitude 21.3°N and longitude 111.2°W which put it about 140 miles (220 km) south-southwest of Cabo San Lucas, Mexico.  Norma was moving toward the northwest at 6 m.p.h. (9 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 1001 mb.

A Tropical Storm Watch was in effect for the portion of the coast from Los Barriles to Todos Santos, Mexico.

Tropical Storm Norma retains some of the structural features that it had when it was a hurricane.  The remnants of a large circular eye form the center of circulation.  A broken ring of strong thunderstorms surrounds the remnants of the eye and the strongest winds are occurring in that ring.  Bands of showers and weaker thunderstorms are revolving around the core of Tropical Storm Norma.  Some of the outer rainbands of Norma are already dropping heavy rain over parts of the southern end of Baja California.

Tropical Storm Norma will move through an environment that will be only marginally favorable for intensification during the next day or so.  Norma will move over water where the Sea Surface Temperature is near 28°C.  An upper level trough west of North America is producing southwesterly winds which are blowing toward the top of the circulation.  Those winds are causing moderate vertical wind shear.  The circulation of Norma may also be drawing some cooler more stable air into the western part of the tropical storm.  Tropical Storm Norma could intensify somewhat during the next 24 hours, but it will eventually move over cooler water and weaken.

A ridge in the middle troposphere located east of Norma is steering the tropical storm toward the northwest and that general motion is expected to continue for another day or so.  When Norma weakens, it will be steered by the winds in the lower levels of the atmosphere.  Those winds will push Tropical Storm Norma more toward the west during the middle of the weak.  On its anticipated track the center of Tropical Storm Norma is forecast to remain west of Baja California.

Hurricane Otis intensified very rapidly on Sunday from a weak tropical storm to a Category 2 hurricane on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Sunday the center of Hurricane Otis was located at latitude 17.0°N and longitude 127.3°W which put it about 1200 miles (1930 km) west-southwest of the southern tip of Baja California.  Otis was moving toward the north at 5 m.p.h. (8 km/h).  The maximum sustained wind speed was 105 m.p.h. (165 km/h) and there were wind gusts to 125 m.p.h. (200 km/h).  The minimum surface pressure was 973 mb.

Hurricane Otis has a very small circulation, which allowed to strengthen very rapidly when the environment became more favorable.  A small eye formed at the center of Hurricane Otis and a tight ring of very strong thunderstorms surrounded the eye.  Those storms began generating upper level divergence which pumped mass away from the center of circulation.  The pressure decreased quickly and the wind speed increased very rapidly.  Hurricane Otis still has a small circulation.  Winds to tropical storm force only extend out about 70 miles (110 km) from the center.

Hurricane Otis may be near its peak intensity.  Otis is still moving over water where the Sea Surface Temperature is near 27°C, but it will soon move over cooler water.  Hurricane Otis will move nearer to the upper level trough west of North America and the hurricane will encounter stronger vertical wind shear.  Because Otis is a small hurricane, it could weaken almost as fast as it intensified.

A small midlevel ridge east of Otis is steering the hurricane toward the north.  Much like Tropical Storm Norma, Otis will be steered by winds lower in the atmosphere when it weakens.  Those winds are forecast to steer Otis more toward the west-southwest later this week.

Tropical Depression 16E Forms, Flood Risk for Mexico

Tropical Depression Sixteen-E formed south of Mexico on Wednesday morning.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Sixteen-E was located at latitude 16.2°N and longitude 101.7°W which put it about 105 miles (165 km) south of Zihuatanejo, Mexico.  It was moving toward the north-northeast 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 1006 mb.

A Tropical Storm Watch was issued for the portion of the coast from Zihuatanejo to Punta Maldonado, Mexico.

A distinct center of circulation formed in a cluster of thunderstorms south of Mexico and that National Hurricane Center designated the system as Tropical Depression Sixteen-E on Wednesday morning.  The circulation of the depression was still organizing.  Several bands of showers and thunderstorms were developing south and east of the center of circulation.  There were fewer showers and thunderstorms in the northwestern quadrant of the circulation and the depression may have been pulling in drier air from Mexico.

The depression has 12 to 18 hours to strengthen before it makes landfall on the coast of Mexico.  It will move over water where the Sea Surface Temperature is near 30°C.  An upper level trough extends from the eastern U.S. to Mexico.  The trough is producing westerly winds which are blowing toward the top of the circulation.  Those winds are generating moderate wind vertical shear, which will inhibit intensification.  Tropical Depression Sixteen-E could strengthen into a tropical storm before it reaches the coast of Mexico.

The upper level trough is forecast to steer Tropical Depression Sixteen-E toward the east.  On its anticipated track the depression could make landfall east of Zihuatanejo in less than 24 hours.  The depression will bring gusty winds, but heavy rain poses a greater threat.  Heavy rain falling in steeper terrain could cause flash floods.

Elsewhere over the Eastern North Pacific Ocean, Tropical Depression Fifteen-E was moving farther away from Mexico.  Tropical Depression Fifteen-E formed when momentum from the upper half of the circulation of former Hurricane Katia spun up a new surface circulation over the Eastern North Pacific.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Fifteen-E was located at latitude 14.9°N and longitude 120.6°W which put it about 890 miles (1435 km) southwest of the southern tip of Baja California.  It was moving toward the west at 9 m.p.h. (15 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 1004 mb.

Hurricane Newton Brings Wind and Heavy Rain to Baja California

Hurricane Newton is bringing wind and heavy rain as it moves over southern Baja California.  At 2:00 p.m. EDT on Tuesday the center of Hurricane Newton was located at latitude 24.7°N and longitude 111.4°W which put it about 75 miles (120 km) west-northwest of La Paz, Mexico.  Newton was moving toward the northwest at 17 m.p.h. (28 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 986 mb.

There are Hurricane Warnings in effect for the portions of the coast from Cabo San Lazaro to Todos Santos, from Los Barriles to Mulege and from Guaymas to Bahia Kino.  Tropical Storm Warnings are in effect for the portions of the coast from Cabo San Lazaro to Punta Abreojos, from Mulege to Bahia San Juan Bautista, from Bahia Tempehuaya to Guaymas and from Bahia Kino to Puerto Libertad.  A Hurricane Watch is in effect for the portion of the coast form Bahia Kino to Puerto Libertad.

Hurricane Newton made landfall on the southern tip of Baja California on Tuesday morning.  It moved along the western coast of the peninsula and the center passed to the west of La Paz, Mexico.  Newton is now moving north across Baja California near Ciudad Constitucion.  Newton is generating winds to hurricane force.  Areas of heavier rain are occurring near La Paz and Mulege.  Very heavy rain is falling where the wind is pushing air up the slopes of mountains and there is a substantial risk of flash flooding in those areas.

The structure of Hurricane Newton is beginning to deteriorate as it interacts with the mountains on Baja California.  The circulation is starting to tilt toward the north as the low level circulation is partially blocked by west coast of Baja while the middle and upper portions of the circulation continue to move north.  The strongest thunderstorms are occurring south of the center of circulation.  Additional strong thunderstorms are occurring rain bands north of the center over the Gulf of California.

Hurricane Newton will weaken as long as the center of circulation is moving over the mountains in southern Baja California.  It is possible that the middle and upper parts of the circulation could temporarily become detached from the existing low level center.  A new low level center could form under the middle and upper parts of the circulation when they emerge over the Gulf of California.  The Sea Surface Temperature in the Gulf of California is 32°C, but Newton will only be over the water for a few hours.  So, the potential for significant re-intensification is slight.

Hurricane Newton is moving around the western end of a ridge of high pressure.  The ridge is steering Newton toward the north.  That general motion is expected to continue for the next few hours and then Hurricane Newton could turn more toward the north-northeast.  On its anticipated track Hurricane Newton will emerge over the Gulf of California near Loreto in about 12 hours.  Newton will make a landfall on the west coast of Mexico in about 18 hours.

Hurricane Newton will continue to bring strong winds and heavy rain to the southern part of Baja California for the rest of Tuesday.  It will also produce heavy rain over portions of western Mexico on Wednesday.  Flash flooding will continue to be a risk in areas of steep terrain.  The remnants of Hurricane Newton could transport moist air over southeastern Arizona and western New Mexico.

Rapidly Intensifying Hurricane Newton Threatens Baja California

Hurricane Newton intensified rapidly from a tropical depression on Monday into a powerful hurricane that threatens Baja California.  At 11:00 p.m. EDT on Monday the center of Hurricane Newton was located at latitude 21.3°N and longitude 109.0°W which put it about 125 miles (200 km) south-southeast of Cabo San Lucas, Mexico.  Newton was moving toward the northwest at 16 m.p.h. (26 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. (170 km/h).  The minimum surface pressure was 979 mb.

The government of Mexico has issued a Hurricane Warning for the portion of the coast from Cabo San Lazaro to Mulege including Cabo San Lucas.  A Tropical Storm Warning has been issued for the portions of the coast from Cabo San Lazaro to Punta Abreojos, from Mulege to Bahia San Juan Bautista and from Mazatlan to Puerto Libertad.  A Hurricane Watch has been issued for the portion of the coast from Guaymas to Puerto Libertad.

The circulation of Hurricane Newton organized very rapidly on Monday.  A primary rainband wrapped most of the way around an eye.  Multiple bands of thunderstorms developed outside the eyewall.  Thunderstorms near the core of Hurricane Newton generated strong upper level divergence which pumped out mass and allowed the winds speeds to increased rapidly.  Newton intensified from a tropical depression into a hurricane in 24 hours.  The maximum sustained wind speed has increased from 40 m.p.h. (65 km/h) 24 hours ago to 90 m.p.h. (150 km/h).

Hurricane Newton is in an environment that could allow it to strengthen until it reaches the southern tip of Baja California.  It is moving over water where the Sea Surface Temperature is 29°C.  The upper level winds are light and there is little vertical wind shear.  When Hurricane Newton reaches Baja California, it will weaken as it crossed over the mountains.  However, it could still be a hurricane when it reaches the warm water in the Gulf of California.

Hurricane Newton is moving around the western end of a mid-level ridge.  The ridge should steer it toward the north-northwest for another 12 hours.  When Newton reaches the end of the ridge, it will turn toward the north-northeast.  On its anticipated track Hurricane Newton will reach the southern portion of Baja California in less than 12 hours.  Newton could emerge over the Gulf of California in about 24 hours.  Newton could still be a hurricane when it reaches the western coast of Mexico near Guaymas on Wednesday.

The Hurricane Intensity Index (HII) for Newton is 13.9.  The Hurricane Size Index (HSI) is 12.2 and the Hurricane Wind Intensity Size Index is 26.1.  Given that Hurricane Newton is likely to intensify until it makes landfall in Baja California, it has the potential to cause regional serious wind damage.  Heavy rain and flash flooding will pose an even greater threat in areas of steep terrain.  Newton has the potential to be a destructive hurricane.

Tropical Storm Newton Forms, Hurricane Warning Issued for Baja California

Tropical Storm Newton formed Sunday within a large area of thunderstorms west of Mexico.  Based on the forecast track and intensity the government of Mexico issued watches and warnings for parts of the west coast of Mexico and Baja California.  A Hurricane Warning was issued for the portion of the coast from La Paz to Santa Fe including Cabo San Lucas.  A Tropical Storm Warning was issued for the portion of the coast from Manzanillo to Cabo Corrientes.  Hurricane Watches were issued for the portions of the coast from La Paz to San Evaristo and from Santa Fe to Cabo San Lazaro.  Tropical Storm Watches were issued for the portions of the coast from San Evaristo to Loreto, from Cabo San Lazaro to Puerto San Andresito and from Mazatlan to Huatabampito.

At 11:00 p.m. EDT on Sunday the center of Tropical Storm Newton was located at latitude 17.0°N and longitude 105.7°W which put it about 490 miles (790 km) southeast of Cabo San Lucas, Mexico.  Newton was moving toward the north-northwest at 8 m.p.h. (13 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 1000 mb.

The circulation of Tropical Storm Newton is still organizing.  There is a broad cyclonic rotation southwest of Manzanillo, Mexico.  Clusters of thunderstorms may be spinning up smaller cyclonic circulations within the larger circulation.  Bands of thunderstorms are developing in the southern and eastern of the portions of the larger cyclonic circulation.  There is upper level divergence pumping mass out to the west of the center, but there is no apparent tight core at the center of the circulation.

Tropical Storm Newton is in an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature is near 30°C.  An upper level ridge over Mexico is producing northeasterly winds which are blowing across the top of Tropical Storm Newton,  The upper level winds are restricting the upper level divergence to the east of Newton,  but the vertical wind shear should not be strong enough to prevent intensification.  It is possible that some drier air from Mexico could be pulled into the eastern half of the circulation.

Tropical Storm Newton is forecast to intensify on Monday.  The broad circulation could slow the rate of intensification until a distinct inner core forms.  Once a core develops, then Tropical Storm Newton could intensify more quickly and a period of rapid intensification may be possible.  Tropical Storm Newton could intensify into a hurricane before it reaches Baja California.

The ridge over Mexico is steering Newton toward the north-northwest and that motion is expected to continue for another day or so.  An upper level trough approaching the west coast of North America is expected to turn Tropical Storm Newton more toward the north as it nears the southern tip of Baja California.  On its anticipated track Tropical Storm Newton could be very near the southern tip of Baja California in about 36 hours.

Linda Rapidly Intensifies Into a Major Hurricane

Hurricane Linda rapidly intensified on Tuesday and it now has a wind speed that qualifies it as a Category 3 Hurricane on the Saffir-Simpson Scale.  This makes Linda the fifth major hurricane in the Eastern North Pacific in 2015.  At 11:00 a.m. EDT on Tuesday the center of Hurricane Linda was located at latitude 21.3°N and longitude 113.9°W which put it about 280 miles (450 km) west-southwest of the southern tip of Baja California.  Linda was moving toward the north-northwest at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 140 m.p.h. (225 km/h).  The minimum surface pressure was 956 mb.

Upper level winds over Linda decreased and the reduction in vertical wind shear allowed it to intensify rapidly during the past 12 hours.  A visible eye and symmetrical eyewall are evidence of a well organized inner core.  Thunderstorms near the center of circulation are generating upper level divergence in all directions which is pumping out mass and causing the pressure to decrease.  Linda could intensify for a few more hours, but it will start to move over much cooler Sea Surface Temperatures (SSTs) later today.  It will be unable to extract enough energy from the cooler water to maintain its intensity and Linda will start to weaken.  As Linda moves farther north, it will also start to encounter stronger upper level winds around the southern portion of an upper level trough near the west coast of the U.S.  Increased vertical wind shear in addition to cooler SSTs will speed up the rate at which Linda weakens.  Since Linda has a large circulation, it could take longer for it to spin down.

An upper level ridge over Mexico is steering Linda toward the north-northwest and that general motion is expected to continue as long as it maintains tall thunderstorms.  When Linda weakens to a tropical storm over cooler water, the circulation will not extend as high in the atmosphere.  After that time Linda will be steered more toward the west by winds lower in the atmosphere.  On its anticipated track Linda will move parallel to the coast of Baja California for several days before turning away from the coast later this week.

Tropical Storm Linda Forms South of Baja California

A spiral band continued to wrap more tightly around the center of circulation inside a large low pressure system west of Mexico on Sunday and the National Hurricane Center designated the system as Tropical Storm Linda.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Linda was located at latitude 14.1°N and longitude 109.0°W which put it about 610 miles (980 km) south of the southern tip of Baja California.  Linda was moving toward the northwest at 12 m.p.h. (19 km/h).  The maximum sustained wind speed was 45 m.p.h. (70 km/h) and there were wind gusts to 60 m.p.h. (95 km/h).  The minimum surface pressure was 1000 mb.

The circulation in Tropical Storm Linda is well organized.  There is one main spiral rainband and multiple outer rainbands.  Outside of the core of the circulation there are fewer thunderstorms east of the center, which could mean that some drier air is being pulled into that part of the storm.  Thunderstorms in the core are generating upper level divergence.  Linda is over water where the Sea Surface Temperatures (SSTs) are above 29°C.  An upper level trough near the west coast of the U.S. and an upper level ridge over northern Mexico are combining to create an outflow channel to the northeast, which is enhancing the flow of mass away from the tropical storm.  There is little vertical wind shear over the top of Linda and the environment is favorable for further intensification.  A period of rapid intensification is possible and Linda is likely to become a hurricane.  Eventually, when it moves farther north, Linda will move into an area of cooler SSTs and more vertical wind shear, which will cause it to weaken.

Linda appears to be moving a little more toward the west-northwest this afternoon.  The upper level ridge over northern Mexico is expected to steer it in a generally northwesterly direction during the next few days.  On its anticipated track, Linda would move west of Baja California during the middle of next week.