Tag Archives: 17E

Hurricanes Norma and Olivia Continue Westward

Hurricanes Norman and Olivia continued to move westward across the Pacific Ocean on Wednesday.  At 5:00 p.m. EDT on Wednesday the center of Hurricane Norman was located at latitude 19.9°N and 148.4°W which put it about 435 miles (700 km) east of Hilo, Hawaii. Norman was moving toward the west at 8 m.p.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).  The Minimum surface pressure was 962 mb.

At 5:00 p.m. EDT on Wednesday the center of Hurricane Olivia was located at latitude 17.3°N and longitude 123.5°W which put it about 960 miles (1550 km) west-southwest of the southern tip of Baja California.  Olivia was moving toward the west-northwest at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 100 m.p.h. (160 km/h) and there were wind gusts to 120 m.p.h. (195 km/h).  The minimum surface pressure was 974 mb.

Although Hurricane Norman was in seemingly a less favorable environment, it intensified on Wednesday while Hurricane Olivia weakened.  The eye of Hurricane Norman became more distinct and it strengthened back to major hurricane status.  Hurricane Olivia weakened to Category 2 on the Saffir-Simpson Scale.  Both hurricanes were similar in size.  Winds to hurricane force extended out about 30 miles (50 km) from the center of Hurricane Norman and about 25 miles (40 km) from the center of Hurricane Olivia.  Winds to tropical storm force extended out about 115 miles (185 km) from the centers of both Hurricane Norman and Hurricane Olivia.

Both hurricanes are forecast to weaken gradually during the next several days.  Hurricane Norman will move over water cooler than 26.5°C.  An upper level trough will produce westerly winds which will blow toward the top of the circulation and cause more vertical wind shear.  The combination of cooler water and more shear will cause Hurricane Norman to weaken. Hurricane Olivia is currently over water where the Sea Surface Temperature is near 28°C, but it too will move over cooler water.  An upper level ridge north of Olivia will produce northwesterly winds which will cause more vertical wind shear.  Hurricane Olivia is also forecast to weaken during the next several days.

The upper level trough is forecast to turn Hurricane Norman toward the northwest on Thursday.  On its anticipated track Hurricane Norman will pass north of the Hawaiian Islands.  The ridge north of Hurricane Olivia is forecast to steer Olivia in a general westerly direction for another four or five days.  On its anticipated track Hurricane Olivia could be east of Hawaii by the end of the weekend.

Tropical Storm Olivia Forms South of Baja California

Tropical Storm Olivia formed south of Baja California on Sunday morning.  At 11:00 a.m. EDT on Sunday the center of Tropical Storm Olivia was located at latitude 17.0°N and longitude 112.4°W which put it about 440 miles (705 km) south-southwest of the southern tip of Baja California.  Olivia 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 circulation of Tropical Storm Olivia was not well organized.  Most of the stronger thunderstorms were occurring in bands southwest of the center of circulation.  The bands in the other parts of the tropical storm consisted primarily of showers and lower clouds.  Olivia was located southeast of an upper level ridge.  The ridge was producing northeasterly winds which were blowing across the top of the circulation.  Those winds were causing vertical wind shear and they were probably the reason why the stronger thunderstorms were confined to the southwestern part of Tropical Storm Olivia.

Tropical Storm Olivia will move into an environment that is more favorable for intensification.  Olivia will move over water where the Sea Surface Temperature is near 29°C.  It will move away from the northeasterly winds in the upper levels and the vertical wind shear is likely to decrease.  Intensification will occur slowly until the circulation becomes more well organized.  Once more thunderstorms form in other parts of the circulation, Tropical Storm Olivia could strengthen more quickly.

Tropical Storm Olivia will move south of a ridge of high pressure over the Eastern North Pacific Ocean.  The ridge will steer Olivia in a westerly direction during the next several days.  On its anticipated track Tropical Storm Olivia will move away from Baja California.

Elsewhere over the Eastern North Pacific Ocean, Hurricane Norman strengthened back to Category 4 on the Saffir-Simpson Scale.  At 11:00 a.m. EDT on Sunday the center of Hurricane Norman was located at latitude 17.6°N and longitude 129.1°W which put it about 1295 miles (2085 km) west-southwest of the southern tip of Baja California.  Norman was moving toward the west-northwest at 18 m.p.h. (30 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 160 m.p.h. (260 km/h).  The minimum surface pressure was 949 mb.  Norman could be northeast of Hawaii in four or five days.

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.

Max Rapidly Intensifies Into a Hurricane Near Acapulco

Tropical Storm Max intensified rapidly into a hurricane on Thursday morning.  At 11:00 a.m. EDT on Thursday the center of Hurricane Max was located at latitude 16.3°N and longitude 99.9°W which put it about 40 miles (65 km/h) south of Acapulco, Mexico.  Max was moving toward the east at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 988 mb.

A Hurricane Warning was in effect for the portion of the coast from Zihuatenajo to Punta Maldonado, Mexico.  A Tropical Storm Warning was in effect for the portion of the coast from Punta Maldonado to Laguas de Chacahua, Mexico.

The circulation of Hurriane Max is quite small.  Winds to hurricane force only extend out about 15 miles (25 km) from the center of circulation.  Winds to tropical storm force extend out about 50 miles (80 km) from the center.  Although the circulation of Hurricane Max is small, it is very well organized.  There is a small circular eye at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds are occurring in that ring of storms.

The center of Hurricane Max is very close to the coast of Mexico.  The outer fringes of the northwestern part of the circulation could already be pulling in some drier air.  Max will make landfall on the coast of Mexico within a few hours and it will start to dissipate as soon as the center make landfall.

The core of Hurricane Max will be capable of causing localized wind damage.  Max will also drop very heavy rain over parts of the states or Guerrero and Oaxaca and flash floods could occur in some areas of steeper terrain.

Elsewhere over the Eastern North Pacific Ocean, Tropical Storm Norma formed to the west of Hurricane Max.  At 11:00 a.m. EDT on Thursday the center of Tropical Storm Norma was located at latitude 17.2°N and longitude 109.5°W which put it about 395 miles (635 km) south of Cabo San Lucas, Mexico.  Norma was moving toward the north at 5 m.p.h. (8 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.  Tropical Storm Norma is forecast to strengthen and move toward Baja California.  Normal could be a hurricane when it approaches southern Baja California in a few days.

Hurricane Paine Prompts Warnings for Part of Baja California

Tropical Storm Paine intensified into a hurricane on Monday and the government of Mexico issued a Tropical Storm Warning for a portion of the west coast of Baja California.  At 8:00 p.m. EDT on Monday the center of Hurricane Paine was located at latitude 23.4°N and longitude 116.5°W which put it about 315 miles (510 km) south-southwest of Punta Eugenia, Mexico.  Paine was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 90 m.p.h. (145 km/h) and there were wind gusts to 105 m.p.h. (170 km/h).  The minimum surface pressure was 979 mb.

There is a Tropical Storm Warning in effect for the portion of the coast from Punta Eugenia to Cabo San Quintin.

The circulation of Hurricane Paine is showing signs of weakening.  It had a well formed eye surrounded by a ring of strong thunderstorms a few hours ago.  The eye is no longer apparent on infrared satellite imagery.  There are still thunderstorms near the center of circulation.  The circulation appears to be pulling cooler, drier and more stable air around the southwestern quadrant of Hurricane Paine.  More thunderstorms are occurring in rainbands in the northwestern quadrant of the circulation.  There are few thunderstorms in the rainbands in the eastern half of Hurricane Paine.

Hurricane Paine will be moving into an environment that will be very unfavorable for a tropical cyclone.  The center is currently moving over water where the Sea Surface Temperature (SST) is near 24°C.  It will move over water where the SST will be less than 22°C on Tuesday.  Less energy in the upper ocean and cooler, more stable air will cause the circulation to weaken and it could weaken quickly.  An upper level low southwest of California will generate some vertical wind shear which could separate the upper part of Hurricane Paine from the lower level circulation as Paine weakens.

Hurricane Paine is moving around the western end of a subtropical ridge over Mexico which is steering Paine toward the north.  On its anticipated track the center of Paine will pass west of Punta Eugenia on Tuesday.  The center or the upper part of the circulation could be near Cabo San Quintin on Wednesday morning.  It is expected to weaken to a tropical depression or a remnant low before it reaches Cabo San Quintin.  However, Paine could bring tropical storm force winds to a portion of the coast, which is why the Tropical Storm Warning was issued.

Tropical Storm Paine Intensifying Quickly Southwest of Baja California

The Eastern North Pacific Ocean continues to spin out tropical cyclones.  Tropical Storm Paine intensified quickly on Sunday as it moved southwest of Baja California.  In 24 hours Paine intensified from a tropical depression to near hurricane strength.  At 11:00 p.m. EDT on Sunday the center of Tropical Storm Paine was located at latitude 19.5°N and longitude 113.8°W which put it about 345 miles (555 km/h) southwest of the southern tip of Baja California.  Paine was moving toward the northwest at 15 m.p.h. (24 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were wind gusts to 85 m.p.h. (135 km/h).  The minimum surface pressure was 992 mb.

Tropical Storm Paine moved through a very favorable environment on Sunday.  The Sea Surface Temperature (SST) was near 28°C.  The upper level winds were light and there was little vertical wind shear.  The favorable environmental conditions allowed a tight inner core to develop rapidly at the center of Tropical Storm Paine.  Infrared and microwave satellite imagery suggest that an eye could be forming at the center of Paine.  A nearly complete ring of strong thunderstorms surrounds the developing eye.  A primary rainband exists in the eastern part of the circulation.  Thunderstorms at the core of Tropical Storm Paine are generating upper level divergence which is pumping out mass in all directions.

Tropical Storm Paine will be in a favorable environment for another 12 to 18 hours.  It is likely to intensify into a hurricane on Monday.  After that time Paine will start to move over cooler SSTs and it should start to weaken.  The air over the cooler SSTs is also drier and more stable and Paine could weaken quickly on Tuesday.

Tropical Storm Paine is moving around the western end of a ridge over Mexico which is steering it toward the northwest.  When Paine reaches the western end of the ridge axis, it will move more toward the north.  On its anticipated track Tropical Storm Paine will pass to the west of the southern end of Baja California during the next several days.

Recon Finds Marty a Hurricane, Mexico Issues Warnings

A reconnaissance plane investigated Marty on Monday afternoon and the data showed that Marty was a hurricane.  At 5:00 p.m. EDT on Monday the center of Hurricane Marty was located at latitude 16.7°N and longitude 102.1°W which put it about 75 miles (125 km) south-southwest of Zihuatanejo, Mexico.  Marty was moving toward the northeast at 6 m.p.h. (10 km/h).  The maximum sustained wind speed was 80 m.p.h. (130 km/h) and there were wind gusts to 95 m.p.h. (155 km/h).  The minimum surface pressure was 986 mb.

The government of Mexico has issued a Hurricane Warning for the portion of the coast from Tecpan de Galeana to Lazaro Cardenas.  A Tropical Storm Warning has been issued for the coast from Tecpan de Galeana to Acapulco.  A Tropical Storm Watch has been issued for the portion of the coast from Lazaro Cardenas to Punta San Telmo.

Although an upper level trough over Mexico has been producing southwesterly flow and causing moderate vertical wind shear over Marty, the vertical integrity of the circulation has been maintained.  So, instead of blowing the top off the circulation, the southwesterly winds have pushed the entire circulation toward the northeast.  As Marty moved over water where the Sea Surface Temperature was near 30°C, it extracted enough energy from the water to intensify into a hurricane.  The southwesterly winds inhibited upper level divergence on the western side of the circulation, but the upper level divergence east of Marty pumped out mass and the pressure decreased.

The environment is not favorable for much more intensification.  The upper level trough is expected to continue to cause vertical wind shear.  In addition, Marty is close enough to the coast of Mexico that the hurricane will begin to pull in some drier air from land.  Marty could intensify a little more, but it is likely to weaken on Tuesday.  If Marty makes landfall, it will weaken quickly.

The upper level trough is pushing Marty northeastward toward the coast of Mexico.  Unless the shear blows the upper part of the circulation away from the lower portion, it will continue to move toward the coast.  Marty could make landfall in 12 to 24 hours, which is why the government of Mexico issued warnings for the coast.  Hurricane Marty could bring strong winds and locally heavy rainfall when it moves inland.

Marty Intensifies and Mexico Issues a Tropical Storm Watch

Tropical Storm Marty intensified on Sunday and the government of Mexico issued a Tropical Storm Watch for a portion of the west coast.  At 2:00 p.m. EDT on Sunday the center of Tropical Storm Marty was located at latitude 15.0°N and longitude 102.8°W which put it about 235 miles (380 km) southwest of Acapulco, Mexico.  Marty was moving toward the north-northeast at 6 m.p.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 997 mb.  A Tropical Storm Watch has been issued for the portion of the coast from Acapulco to Lazaro Cardenas, Mexico.

The structure of Tropical Storm Marty improved on Sunday morning.  A long rainband stretched around the southern and eastern sides of the circulation and more thunderstorms developed near the center or circulation.  Marty is over water where the Sea Surface Temperature (SST) is near 30°C, which means there is a lot of energy in the upper ocean.  However, an upper level trough extends from the western Gulf of Mexico across northern Mexico.  The upper level trough is causing westerly winds, which could already be producing vertical wind shear over the northern half of the circulation of Tropical Storm Marty.  Very warm SSTs mean that the potential for intensification exists, but the vertical wind shear will limit how much intensification actually occurs.  If the upper level winds get stronger, they could shear the top half of the circulation away from the bottom half and cause Marty to dissipate.

The upper level trough is beginning to steer Marty toward the north-northeast and the tropical storm is likely to move in that direction over the short term.  The ultimate track of Marty will be determined by the vertical integrity of the circulation and the strength of the vertical wind shear.  If the wind shear is not too strong and the upper and lower portions of the circulation remain together, then the trough will steer all of Marty toward the northeast.  In that case it could make landfall on the Mexican coast in several days.  However, if the vertical wind shear blows then top off of the circulation, then the upper level portion will move northeast toward Mexico, while the lower part of the tropical storm is left behind.  The upper half of the circulation could still bring heavy rain and the potential for floods to parts of Mexico, even if the surface circulation does not make landfall.