Category Archives: Eastern and Central Pacific

TCs between Mexico and Hawaii

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.

Hurricane Lester Passing North of Hawaii

Hurricane Lester passed north of Hawaii on Saturday.  All Hurricane Watches were cancelled, although the surf on the north coasts of the islands should be increased by the waves generated by Hurricane Lester.  At 5:00 p.m. EDT on Saturday the center of Hurricane Lester was located at latitude 22.4°N and longitude 155.4°W which put it about 175 miles (285 km) east-northeast of Honolulu, Hawaii.  Lester was moving toward the west-northwest at 17 m.p.h. (28 km/h).  The maximum sustained wind speed was 85 m.p.h. (140 km/h) and there were wind gusts to 100 m.p.h. (160 km/h).  The minimum surface pressure was 985 mb.

Hurricane Lester weakened slowly on Saturday as it moved north of the Hawaiian Islands.  An upper level trough northwest of Lester produced southwesterly winds that blew across the top of the hurricane.  The vertical wind shear tilted the circulation toward the northeast with height.  The wind shear also inhibited the upper level divergence to the south of the center of Lester.  Less upper level divergence meant that the hurricane could not pump out as much mass and the surface pressure slowly rose.

Hurricane Lester is moving through an environment that is likely to weaken it further.  Lester is moving over water where the Sea Surface Temperature (SST) is 27°C.  So, there is enough energy to support the hurricane.  However, the upper level trough will continue to create vertical wind shear and the shear will continue to weaken Hurricane Lester.

Hurricane Lester is moving around the western end of a subtropical ridge which is steering toward the west-northwest.  That general motion is expected to continue for several more days.  When Hurricane Lester gets farther north the westerlies in the middle latitudes will turn it toward the northeast.  On its anticipated track Hurricane Lester will stay north of the Hawaiian Islands.

Hurricane Watch Issued for Hawaii as Hurricane Lester Moves Closer

As Hurricane Lester moved steadily closer to Hawaii on Thursday, a Hurricane Watch was issued for Hawaii County and Maui County including Maui, Molokai, Lanai and Kahoolawe.

At 8:00 p.m. EDT on Thursday the center of Hurricane Lester was located at latitude 18.5°N and longitude 145.4°W which put it about 640 miles (1030 km) east of Hilo, Hawaii.  Lester was moving toward the west 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 145 m.p.h. (235 km/h).  The minimum surface pressure was 960 mb.

The symmetrical circulation of Hurricane Lester is very well organized.  There is a circular eye with a diameter of 25 miles (40 km).  A ring of strong thunderstorms completely surrounds the eye.  Multiple spiral rainbands are rotating around periphery of the circulation.  Hurricane Lester is generating strong upper level divergence which is pumping mass out in all directions.

Hurricane Lester is currently moving through a favorable environment.  It is over water where the Sea Surface Temperature is near 27°C.  The upper level winds are light and there is little vertical wind shear.  Hurricane Lester will be moving over some of the same water that Hurricane Madeline passed over a few days ago.  If Madeline stirred any cooler water to the surface, it could cause Hurricane Lester to weaken.  When Hurricane Lester gets closer to Hawaii an upper level trough will produce stronger upper level southwesterly winds and the wind shear will increase.  Lester should weaken as it gets closer to Hawaii.

A subtropical ridge has been steering Hurricane Lester toward the west.  The western end of the ridge is expected to weaken and that will cause Lester to move more toward the west-northwest.  On its anticipate track Hurricane Lester could approach Hawaii on Saturday morning.

Hurricane Warning for Hawaii as Madeline Moves Closer

The Central Pacific Hurricane Center issued a Hurricane Warning for Hawaii County (i.e. the Big Island of Hawaii) as Hurricane Madeline moved steadily closer on Tuesday.  A Tropical Storm Watch has been issued for Maui County including Maui, Molokai and Lanai.

At 11:00 p.m. EDT on Tuesday the center of Hurricane Madeline was located at latitude 19.3°N and longitude 150.3°W which put it about 315 miles (505 km) east of Hilo, Hawaii.  Madeline was moving toward the west at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 110 m.p.h. (175 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 972 mb.

A subtropical ridge has been steering Hurricane Madeline toward the west.  The ridge is expected to strengthen and steer Madeline more toward the west-southwest for the next day or two.  On its anticipated track Hurricane Madeline could approach the island of Hawaii in about 30 hours.

An upper level trough north of Hawaii has been producing westerly winds which are causing vertical wind shear.  The westerly winds are restricting the upper level divergence to the west of Hurricane Madeline.  However, thunderstorms in the core of the hurricane have strengthened periodically and reduced the impact of the wind shear.  The shear is expected to continue and Hurricane Madeline is forecast to slowly weaken.  However, Madeline is moving over water where the Sea Surface Temperature is near 27°C, and it could move over warmer water if it moves toward the west-southwest.

Madeline is expected to be a hurricane when it moves past the island of Hawaii.  On its anticipated track the greatest threat would be to the southern half of the island.  Madeline is a compact hurricane and winds to hurricane force only extend out about 25 miles (40 km) from the center.  Hurricane Madeline will be capable of causing localized serious wind damage.  It may also produce heavy rain and flash flooding, especially where the wind blows up the slopes.

Major Hurricanes Madeline and Lester Moving Toward Hawaii

Hurricanes Madeline and Lester intensified quickly on Monday into Major Hurricanes as they moved toward Hawaii.  The approach of Hurricane Madeline prompted the Central Pacific Hurricane Center to issue a Hurricane Watch for Hawaii County.  Both hurricanes have the potential to affect the weather around Hawaii during the next few days.

At 5:00 p.m. EDT on Monday the center of Hurricane Madeline was located at latitude 18.6°N and longitude 145.5°W which put it about 630 miles (1015 km) east of Hilo, Hawaii.  Madeline was moving toward the west-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 135 m.p.h. (220 km/h).  That made Hurricane Madeline the equivalent of a Category 3 hurricane on the Saffir-Simpson Scale.  The minimum surface pressure was 966 mb.

At 5:00 p.m. EDT on Monday the center of Hurricane Lester was located at latitude 18.0°N and longitude 130.5°W which put it about 1375 miles (2210 km) west of the southern tip of Baja California.  Lester was moving toward the west at 14 m.p.h. (22 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 150 m.p.h. (240 km/h).  That made Hurricane Lester a Category 4 hurricane on the Saffir-Simpson Scale.  The minimum surface pressure was 951 mb.

Both Hurricanes Madeline and Lester are relatively compact hurricanes and the winds to hurricane force only extend out about 30 miles (50 km) from the center of circulation.  In Hurricane Madeline the Hurricane Intensity Index (HII) is 20.6.  The Hurricane Size Index (HSI) is 11.4 and the Hurricane Wind Intensity Size Index (HWISI) is 32.0.  Hurricane Lester is stronger, but slightly smaller.  The HII for Hurricane Lester is 25.1, while HSI is 10.3 and HWISI is 35.4.

Both hurricanes have well formed symmetrical eyes surrounded by rings of tall thunderstorms.  Each is producing well developed upper level divergence which is pumping out mass in all directions.  Hurricane Madeline has more spiral rainbands, and Hurricane Lester shows some indications that the structure might be assuming more of the shape of an annular hurricane.

Hurricanes Madeline and Lester responded to a favorable environment by intensifying rapidly on Monday.  The maximum sustained wind speed in Hurricane Madeline increased from 65 m.p.h. (105 km/h) to 115 m.p.h. (185 km/h) during the past 24 hours.  The maximum sustained wind speed in Hurricane Lester increased from 85 m.p.h. (140 km/h) to 130 m.p.h. (215 km/h) during the past 24 hours.

Hurricanes Madeline and Lester will remain in a favorable environment during the short term.  They are moving over water where the Sea Surface Temperatures (SSTs) are near 27.5°C.  The upper level winds are light and there is little vertical wind shear.  Thus, both hurricanes could maintain their intensity for another 12 to 24 hours.  When the hurricanes move closer to Hawaii, they will move over slightly cooler SSTs.  In addition, an upper level trough approaching from the northwest could increase the vertical wind shear later this week.  Hurricane Lester may also move over some cooler water mixed to the surface by Hurricane Madeline.

A subtropical ridge is steering Hurricanes Madeline and Lester toward the west and that general motion is expected to continue for the next several days.  On its anticipated track Hurricane Madeline could approach Hawaii in a couple of days.  Hurricane Lester could approach Hawaii in about five days.

 

Tropical Storm Madeline Forms East of Hawaii

A cluster of thunderstorms between Hawaii and Mexico developed enough organization on Friday night that the National Hurricane Center designated the system as Tropical Storm Madeline.  At 11:00 p.m. EDT on Friday the center of Tropical Storm Madeline was located at latitude 13.9°N and longitude 137.4°W which put it about 1235 miles (1990 km) east-southeast of Hilo, Hawaii.  Madeline was moving toward the west-northwest at 12 m.p.h. (19 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.

The circulation of Tropical Storm Madeline is still organizing.  A primary spiral band wraps around the western side of the circulation.  There are additional spiral bands of the thunderstorms in the southern part of the tropical storm.  The thunderstorms in the primary rainband are generating upper level divergence which it pumping mass out primarily to the west of tropical storm Madeline.

Tropical Storm Madeline is moving through an environment that is favorable for intensification.  It is moving over water where the Sea Surface Temperature (SST) is near 29°C.  The upper level winds are light and there is not much vertical wind shear.  Tropical Storm Madeline is expected to intensify steadily and it could become a hurricane by the end of the weekend.  In a few days Madeline will move over cooler SSTs and into an area where the is more vertical wind shear.  When that happens, Madeline will start to weaken.

A subtropical high is steering Tropical Storm Madeline toward the west-northwest and a general west-northwest or westerly motion is expected to continue during the next few days.  On its anticipated track Madeline could approach the Hawaiian Islands in about five days.

Tropical Storm Lester Forms West of Mexico

Tropical Storm Lester became the 12th named tropical storm to form over the Eastern North Pacific Ocean during 2016 on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Lester was located at latitude 16.9°N and longitude 113.4°W which put it about 470 miles (760 km) south-southwest of the southern tip of Baja California.  Lester was moving toward the west-northwest at 10 m.p.h. (16 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 1000 mb.

Tropical Storm Lester formed when a distinct center of circulation developed within a tropical wave.  The core of the tropical storm is still consolidating.  There are thunderstorms near the center of circulation and there are spiral bands rotating around the core of Tropical Storm Lester.  The thunderstorms near the center are generating upper level divergence which is pumping away may to the south of the tropical storm.  There are hints of the possible formation of an eye on some satellite images.

Tropical Storm Lester is moving through an environment that is generally favorable for intensification.  It is moving over water where the Sea Surface Temperature is around 30°C.  An upper level ridge northwest of Lester is generating northerly winds which are blowing across the top of the tropical storm.  The northerly winds are producing some vertical wind shear, but the shear is only slowing the intensification process.  Tropical Storm Lester is expected to continue to intensify and it could become a hurricane.

A subtropical ridge is steering Tropical Storm Lester toward the west-northwest and that general motion is expected to continue.  On its anticipated track Tropical Storm Lester will move farther away from Mexico and it currently poses no threat to land.

Tropical Storm Kay Forms South of Baja California

A distinct center of circulation consolidated within a cluster of thunderstorms south of Baja California and the National Hurricane Center designated the system as Tropical Storm Kay.  At 5:00 a.m. EDT on Friday the center of Tropical Storm Kay was located at latitude 18.4°N and longitude 110.9°W which put it about 315 miles (510 km) south-southwest of the southern tip of Baja California.  Kay was moving toward the northwest at 7 m.p.h. (11 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 1005 mb.

The circulation of Tropical Storm Kay is only moderately well organized.  Most of the stronger thunderstorms are occurring in a band that wraps around the western side of the circulation.  There are also scattered thunderstorms in broken bands around the tropical storm, but much of the convection is occurring in the western half of Kay.  The thunderstorms in the primary rainband are generating some upper level divergence which is moving air to the west of the Tropical Storm Kay.

Tropical Storm Kay is moving through an environment that is marginally favorable for intensification in the short term.  Kay is moving over water where the Sea Surface Temperature (SST) is near 29°C.  An upper level ridge to the north of Kay is generating northeasterly winds which are blowing across the top of the tropical storm.  The moderate vertical wind shear is inhibiting intensification and it is also contributing to the asymmetrical distribution of thunderstorms.  The effect of the warm SSTs could allow for some additional intensification during the next 24 hours.  Tropical Storm Kay will be moving over cooler SSTs during the weekend and the effect of the effect of the cooler water with less energy will weaken the storm.

Tropical Storm Kay is moving around the western end of a subtropical ridge and that is steering the storm toward the northwest.  That general motion is expected to continue for another 24 to 48 hours.  When Tropical Storm Kay moves over cooler SSTs, the thunderstorms will weaken and the circulation will become shallower.  The shallower circulation will be steered by the winds closer to the surface, which are expected to turn Tropical Storm Kay more toward the west in a couple of days.  On its anticipated track Tropical Storm Kay will pass west of Baja California.