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Hurricane Hector Passes South of Hawaii

Powerful Hurricane Hector passed south of Hawaii on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane Hector was located at latitude 16.7°N and longitude 156.8°W which put it about 325 miles (525 km) south-southeast of Honolulu, Hawaii.  Hector was moving toward the west at 16 m.p.h. (26 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).  The minimum surface pressure was 959 mb.

The circulation of Hurricane Hector remained circular and symmetrical.  Information from radar and satellites indicated that Hurricane Hector had a double eyewall structure.  There was a small inner eye surrounded by an inner eyewall.  The inner eyewall was thin and it appeared to be weakening.  A clear area, sometimes called a moat, surrounded the inner eyewall.  A second thicker eyewall surrounded the moat.  Several shorter bands of of showers and thunderstorms were revolving around the core of Hector.  The circulation of Hurricane Hector was relatively small.  Winds to hurricane force extended out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force only extended out about 95 miles (155 km) from the center.

Hurricane Hector exhibited a structure that is sometimes called an annular hurricane.  Annular hurricanes often achieve an equilibrium with their environment which can persist for days if there is not much wind shear.  Hector will move over water where the Sea Surface Temperature is between 27°C and 28°C.  It will move through a region where there is little vertical wind shear.  Hurricane Hector will remain a strong hurricane and it could strengthen during the next 24 to 48 hours, if the inner eyewall dissipates completely.

Hurricane Hector will move south of the subtropical high pressure system over the Central Pacific.  The high will steer Hector toward the west for several more days.  On its anticipated track Hurricane Hector will remain south of Hawaii.

Elsewhere over the Eastern North Pacific Ocean, Hurricane John weakened west of Baja California and Tropical Storm Kristy exhibited little change on Wednesday.  At 11:00 p.m. EDT on Wednesday the center of Hurricane John was located at latitude 23.1°N and longitude 114.4°W which put it about 285 miles (460 km) west of the southern tip of Baja California.  John was moving toward the northwest at 16 m.p.h. (26 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 983 mb.

At 11:00 p.m. EDT on Wednesday the center of Tropical Storm Kristy was located at latitude 15.3°N and longitude 130.0°W which put it about 1410 miles (2220 km) west-southwest of the southern tip of Baja California.  Kristy 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.

Hurricane Hector Prompts Tropical Storm Warning for Hawaii

The imminent approach of Hurricane Hector prompted the issuance of a Tropical Storm Warning for Hawaii County.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Hector was located at latitude 16.6°N and longitude 150.7°W which put it about 370 miles (590 km) east-southeast of South Point, Hawaii.  Hector was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 130 m.p.h. (215 km/h) and there were wind gusts to 155 m.p.h. (250 km/h).  The minimum surface pressure was 952 mb.

The circulation of Hurricane Hector remains very well organized and it seems to have reached an equilibrium with its environment.  There is a 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 rings of storms.  Several bands of showers and thunderstorms are revolving around the core of Hurricane Hector.  Storms around the core were generating well developed upper level divergence was pumping mass away from the hurricane.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 115 miles (185 km) from the center.

Hurricane Hector will remain in a favorable environment for several more days.  Hector will move over water where the Sea Surface Temperature is near 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  Hurricane Hector will remain a strong hurricane for the next few days.

Hurricane Hector will move south of the subtropical ridge over the Central Pacific Ocean.  The ridge will steer Hector in a general westerly direction for several more days.  On its anticipated track the center of Hurricane Hector will pass south of Hawaii.  However, rainbands on the north side of Hector could bring winds to tropical storm force to the Big Island of Hawaii, which is why the Tropical Storm Warning was issued for Hawaii County.

Recon Finds Hurricane Hector Nearly at Category 5

An Air Force Reserve Hurricane Hunter reconnaissance aircraft found on Monday that Hurricane Hector had strengthened to nearly Category 5 on the Saffir-Simpson Scale.  At 5:00 p.m. EDT on Monday the center of Hurricane Hector was located at latitude 15.2°N and longitude 143.1°W which put it about 870 miles (1405 km) east-southeast of South Point, Hawaii.  Hector was moving toward the west at 16 m.p.h. (26 km/h).  The maximum sustained wind speed was 155 m.p.h. (250 km/h) and there were wind gusts to 190 m.p.h. (305 km/h).  The minimum surface pressure was 936 mb.  A Tropical Storm Watch is in effect for Hawaii County.

Hurricane Hector has a very symmetrical, well formed circulation.  There is a circular eye with a diameter of 19 miles (31 km) at the center of circulation.  The eye is surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Hector.  Storms near the core were generating well developed upper level divergence which was pumping mass away from the hurricane in all directions.

The circulation of Hurricane Hector is compact.  Winds to hurricane force extend out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extend out about 105 miles (170 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Hector is 33.3.  The Hurricane Size Index (HSI) is 12.1 and the Hurricane Wind Intensity Size Index (HWISI) is 45.4.

Hurricane Hector will remain in its current environment for several more days.  Hector will move over water where the Sea Surface Temperature is near 27°C.  It will move through a region where the upper level winds are weak and there will be little vertical wind shear.  If a rainband wraps around the eye and eyewall, then an eyewall replacement cycle could occur.  Eyewall replacement cycles cause weakening at first while the inner eyewall dissipates.  Hurricanes can restrengthen if the outer eyewall starts for move closer to the center of circulation.  Most very powerful hurricanes only stay very intense for 12 to 24 hours before they start to weaken.  If takes a lot of energy to drive an intense hurricane and if Hector moves into an environment that is a little less favorable, then it could weaken.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern and Central North Pacific Ocean.  The subtropical high will steer Hector in a general westerly direction during the next few days.  On its anticipated track Hurricane Hector will be southeast of Hawaii by Wednesday morning.  The core of Hurricane Hector is forecast to pass south of Hawaii, but it could come close enough to cause tropical storm force winds which is the reason for the Tropical Storm Watch.

Powerful Hurricane Hector Approaches Central Pacific, Ileana Forms South of Mexico

Powerful Hurricane Hector approached the Central Pacific Ocean on Sunday while Tropical Storm Ileana and Tropical Depression Twelve-E formed south of Mexico.  The government of Mexico issued a Tropical Storm Watch for a portion of the coast because of the potential impacts of Tropical Storm Ileana.  At 8:00 p.m. EDT on Sunday the center of Hurricane Hector was located at latitude 14.5°N and longitude 138.6°W which put it about 1170 miles (1885 km) east-southeast of South Point, Hawaii.  Hector was moving toward the west at 13 m.p.h. (20 km/h).  The maximum sustained wind speed was 140 m.p.h. (220 km/h) and there were wind gusts to 165 m.p.h. (270 km/h).  The minimum surface pressure was 947 mb.

The circulation of Hurricane Hector was very well organized.  There was a circular eye with a diameter of 18 miles (29 km) at the center of circulation.  The eye was surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  Several bands of showers and thunderstorms were revolving around the core of Hurricane Hector.  Storms in the core of Hector were generating strong upper level divergence which was pumping mass away from the hurricane.

The circulation of Hurricane Hector remained compact.  Winds to hurricane force extended out about 30 miles (50 km) from the center of circulation.  Winds to tropical storm force extended out about 100 miles (160 km) from the center.  The Hurricane Intensity Index (HII) for Hurricane Hector was 28.3.  The Hurricane Size Index (HSI) was 9,9 and The Hurricane Wind Intensity Size Index (HWISI) was 38.2.

Hurricane Hector will move through an environment capable of supporting a strong hurricane during the next day or two.  It will move over water where the Sea Surface Temperature is near 27°C and 28°C.  Hector will move through an area where the upper level winds are weak and there will be little vertical wind shear.  An eyewall replacement cycle could occur if a rainband wraps around the existing eye and eyewall.  It would cause fluctuations in the intensity of Hurricane Hector.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The high will steer Hurricane Hector toward the west during the next several days.  On its anticipated track Hurricane Hector will be southeast of Hawaii in about three days.

Tropical Storm Ileana developed south of Mexico on Sunday.  The government of Mexico issued a Tropical Storm Watch for the portion of the coast from Lazaro Cardenas to Cabo Corrientes.  At 8:00 p.m. EDT on Sunday the center of Tropical Storm Ileana was located at latitude 13.9°N and longitude 98.9°W which put it about 210 miles (335 km) south-southeast of Acapulco, Mexico.  Ileana was moving toward the west-northwest at 12 m.p.h. (19 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 1000 mb.

Tropical Depression Twelve-E formed west of Tropical Storm Ileana on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Depression Twelve-E was located at latitude 14.6°N and longitude 105.8°W which put it about 320 miles (515 km) south-southwest of Manzanillo, Mexico.  It was moving toward the northwest at 7 m.p.h. (11 km/h).  The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there wind gusts to 45 m.p.h. (75 km/h).  The minimum surface pressure was 1006 mb.

There is uncertainty about the future interaction of Tropical Storm Ileana and Tropical Depression Twelve-E.  The circulation of Tropical Depression Twelve-E is much larger than the circulation of Tropical Storm Ileana.  In addition, upper level divergence form the depression could cause vertical wind shear over Tropical Storm Ileana.  In one possible scenario Tropical Storm Ileana moves toward Tropical Depression Twelve-E and it is absorbed by the larger circulation.  Another possibility is that Tropical Storm Ileana moves around the eastern periphery of the circulation of the tropical depression,  The second scenario would bring Tropical Storm Ileana close to the west coast of Mexico which is why the Tropical Storm Watch was issued.

Hector Strengthens Into a Major Hurricane

Hurricane Hector strengthened to Category 3 on the Saffir-Simpson Scale on Friday night which made it a major hurricane.  At 11:00 p.m. EDT on Friday the center of Hurricane Hector was located at latitude 14.2°N and longitude 130.9°W which put it about 1640 miles (2640 km) east of Hilo, Hawaii.  Hector was moving toward the west at 12 m.p.h. (19 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 967 mb.

Hurricane Hector strengthened on Friday night despite having a double eyewall structure.  There was a small inner eye surrounded by a ring of strong thunderstorms and the strongest winds were occurring in that ring of storms.  A clear ring sometimes called a moat surrounded the inner eyewall.  The moat was surrounded by an outer eyewall that consisted of showers and thunderstorms.  Several other bands of showers and thunderstorms were revolving around the concentric eyewalls.  Thunderstorms in the core of Hurricane Hector were generating strong upper level divergence which was pumping mass away from the hurricane in all directions.

The circulation of Hurricane Hector was small.  Winds to hurricane force only extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force only extended out about 70 miles (110 km) from the center.

Hurricane Hector will move through an environment favorable for intensification during the weekend.  Hector will move over water where the Sea Surface Temperature is between 27°C and 28°C.  It will move through an area where the upper level winds are weak.  However, the existence of concentric eyewalls means that an eyewall replacement cycle will occur at some time in the future.  The eyewall replacement will cause Hurricane Hector to weaken when the inner eyewall dissipates and the strongest winds are found in the outer eyewall.  Hector could begin to intensify again if the outer eyewall begins to contract closer to the center of circulation.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean and the high will steer Hector westward during the next few days.  On its anticipated track Hurricane Hector could be southeast of Hawaii in four or five days.

Hector Rapidly Intensifies Into a Hurricane

Former Tropical Storm Hector rapidly intensified a hurricane on Thursday morning.  At 11:00 a.m. EDT on Thursday the center of Hurricane Hector was located at latitude 14.2°N and longitude 124.6°W which put it about 1135 miles (1825 km) west-southwest of the southern tip of Baja California.  Hector was moving toward the west at 14 m.p.h. (22 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 987 mb.

The circulation of Hurricane Hector rapidly became more organized on Thursday morning.  A band of showers and thunderstorms wrapped tightly around the center of circulation.  A small eye appeared on satellite images at the center of Hurricane Hector.  A ring of strong thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms.  Several other bands of showers and thunderstorms were revolving around the core of the hurricane.  Storms near the core were generating strong upper level divergence which was pumping mass away from the hurricane.  The circulation of Hurricane Hector was relatively small.  Winds to hurricane force extended out about 20 miles (30 km) from the center of circulation.  Winds to tropical storm force extended out about 60 miles (95 km) from the center.

Hurricane Hector will move through an environment favorable for intensification during the next several days.  Hector will move over water where the Sea Surface Temperature is between 27°C and 28°C.  An upper level ridge northeast of Hurricane Hector will produce easterly winds which will blow toward the top of the circulation.  However, the strongest easterly winds will be north of Hector and the vertical wind shear should not be too great over the hurricane.  Hurricane Hector is likely to continue to intensify and it could become a major hurricane.

Hurricane Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The subtropical high will steer Hector in a generally westerly direction during the next few days.  On its anticipated track Hurricane Hector will cross into the Central Pacific late in the weekend.  Hector could be southeast of Hawaii early next week.

Tropical Storm Hector Forms Southwest of Baja California

Tropical Storm Hector formed southwest of Baja California on Tuesday evening.  At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Hector was located at latitude 13.0°N and longitude 118.2°W which put it about 875 miles (1405 km) southwest of the southern tip of Baja California.  Hector was moving toward the west-northwest 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 1006 mb.

A distinct low level center of circulation formed within an area of thunderstorms southwest of Baja California on Tuesday and the National Hurricane Center designated the system as Tropical Storm Hector.  The circulation of Tropical Storm Hector was still organizing.  Many of the stronger thunderstorms were occurring in two bands south and west of the center of circulation.  Additional bands of showers and storms were developing north and southeast of the center.  Thunderstorms near the center were beginning to generate upper level divergence which was pumping mass away from the tropical storm.

Tropical Storm Hector will move through an environment that is mostly favorable for intensification.  Hector will move over water where the Sea Surface Temperature is near 28°C.  An upper level ridge centered near Baja California was generating northeasterly winds which were blowing toward the top of the circulation.  Those winds were causing some vertical wind shear, but the shear will not be strong enough to prevent intensification.  Hector will intensify over the next several days and it will likely become a hurricane by Thursday night.

Tropical Storm Hector will move south of the subtropical high pressure system over the Eastern North Pacific Ocean.  The subtropical high will steer Hector in a general westerly direction.  On its anticipated track Tropical Storm Hector will move away from Mexico and toward the Central Pacific Ocean.

Tropical Storms Hilary and Irwin Interact As They Weaken

Tropical Storms Hilary and Irwin started to interact on Thursday as both storms began to weaken.  At 11:00 p.m. EDT on Thursday the center of Tropical Storm Hilary was located at latitude 18.3°N and longitude 117.3°W which put it about 575 miles (925 km) west-southwest of the southern tip of Baja California.  Hilary was moving toward the west-northwest at 8 m.p.h. (13 km/h).  The maximum sustained wind speed was 70 m.p.h. (110 km/h) and there were gust to 85 m.p.h. (140 m.p.h.).  The minimum surface pressure was 992 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Storm Irwin was located at latitude 14.9°N and longitude 124.6°W which put it about 1105 miles (1780 km) west-southwest of the southern tip of Baja California.  Irwin was moving toward the west at 2 m.p.h. (3 km/h).  The maximum sustained wind speed was 60 m.p.h. (95 km/h) and there were gusts to 75 m.p.h. (120 km/h).  The minimum surface pressure was 1000 mb.

Hilary weakened below hurricane intensity on Thursday.  It appeared that the circulation drew in drier more stable air around the northwestern side of the circulation.  The drier air reduced the formation of showers and thunderstorms and the core of the circulation weakened.  At the same time upper level divergence from Tropical Storm Hilary increased the vertical wind shear over Tropical Storm Irwin.  Irwin was over water where the Sea Surface Temperature is near 28.5°C and it was able to extract enough energy from the ocean to maintain most of its intensity.

Tropical Storms Hilary and Irwin will move over water where the Sea Surface Temperature is near 28°C on Friday.  However, the combination of drier, more stable air and vertical wind shear is likely to keep both of the storms from strengthening.  Hilary and Irwin will move over cooler water during the weekend and both tropical storms are likely to weaken when that occurs.

Tropical Storm Hilary is being steering toward the west-northwest by a subtropical high pressure system to the north of the tropical storm.  Hilary is forecast to continue moving toward the west-northwest.  Tropical Storm Hilary is larger than Irwin.  Winds to tropical storm force extend out about 110 miles (180 km) in Tropical Storm Hilary.  Winds to tropical storm force extend out about 70 miles (110 km) in Tropical Storm Irwin.

The centers of the two tropical storms are only about 540 miles (870 km) apart.  When Tropical Storm Hilary passes north of Irwin, Tropical Storm Irwin is forecast to start to revolve around the larger Tropical Storm Hilary.  Irwin is expected to turn toward the north after Tropical Storm Hilary passes by.  Some models are forecasting the that the centers of the two tropical storms will approach each other and the larger Tropical Storm Hilary will eventually absorb Tropical Storm Irwin.

Hurricanes Hilary and Irwin Churn Over Eastern Pacific

Hurricanes Hilary and Irwin continued to churn over the Eastern North Pacific Ocean on Tuesday.  At 11:00 p.m. EDT on Tuesday the center of Hurricane Hilary was located at latitude 16.0°N and longitude 109.8°W which put it about 475 miles (765 km) south of the southern tip of Baja California.  Hilary was moving toward the west-northwest at 12 m.p.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.

At 11:00 p.m. EDT on Tuesday the center of Hurricane Irwin was located at latitude 16.1°N and longitude 120.9°W which put it about 855 miles (1375 km) west-southwest of the southern tip of Baja California.  Irwin was moving toward the west at 8 m.p.h. (13 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. (165 km/h).  The minimum surface pressure was 980 mb.

Hilary is the larger and stronger of the two hurricanes.  Hurricane Hilary has a small circular eye surrounded by a ring of strong thunderstorms.  A rainband spirals around the western and southern sides of the core of the circulation.  Thunderstorms in the core are generating strong upper level divergence which is pumping out mass in all directions.  Winds to tropical storm force extend out about 90 miles (145 km) from the center.

Hurricane Irwin has a smaller circulation.  Irwin has a small eye.  Most of the thunderstorms are occurring in the northwestern quadrant of the circulation.  Winds to tropical storm force extend out only about 70 miles (110 km) from the center of circulation.

Hurricane Hilary is moving through a more favorable environment.  Hilary is moving over water where the Sea Surface Temperature is near 29°C.  The upper level winds are weak and there is little vertical wind shear near Hilary.  Hurricane Irwin is moving over water where the Sea Surface Temperature is near 28°C.  An upper level low northwest of Irwin appears to be producing westerly winds which are undercutting the upper level divergence generated by thunderstorms near the core of the hurricane.  Some drier air also seems to wrapping around the eastern side of the circulation.

Hurricane Hilary is moving faster than Hurricane Irwin and Hilary is getting closer to Irwin.  The two hurricanes are expected to interact later this week.  Since Hilary is bigger and stronger than Irwin, Hilary is forecast to become the dominant circulation.  Hurricane Hilary is expected to continue to move in west-northwesterly direction.  When Hilary gets closer to Hurricane Irwin, Irwin is forecast to begin to revolve around Hilary in an interaction called the Fujiwhara effect.  On their anticipated tracks Hurricanes Hilary and Irwin are expected to remain south of the southern tip of Baja California.

Tropical Storm Irwin Forms, Greg Gets Larger, Hilary Strengthens

Tropical Depression Ten-E intensified into Tropical Storm Irwin, the circulation of Tropical Storm Greg increased in size and Tropical Storm Hilary strengthened on Sunday.  At 5:00 p.m. EDT on Sunday the center of Tropical Storm Irwin was located at latitude 14.9°N and longitude 116.6°W which put it about 705 miles (1135 km) southwest of the southern tip of Baja California.  Irwin was moving toward the west at 8 m.p.h. (13 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.

At 5:00 p.m. EDT on Sunday the center of Tropical Storm Greg was located at latitude 14.4°N and longitude 130.1°W which put it about 1445 miles (2325 km) west-southwest of the southern tip of Baja California.  Greg was moving toward the west at 14 m.p.h. (22 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.

At 5:00 p.m. EDT on Sunday the center of Tropical Storm Hilary was located at latitude 14.9°N and longitude 102.9°W which put it about 410 miles (660 km) south-southeast of Manzanillo, Mexico.  Hilary was moving toward the west-northwest at 9 m.p.h. (15 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 was 999 mb.

A primary rainband wrapped around the western and southern sides of the center of circulation of Tropical Depression Ten-E and the National Hurricane Center upgraded the system to Tropical Storm Irwin.  Several other bands of showers and thunderstorms were developing over the southern half of the circulation.  There were fewer showers and thunderstorms in the northern half of the circulation.  Thunderstorms near the center of circulation were generating some upper level divergence.

Tropical Storm Irwin will move through an environment that will be somewhat favorable for intensification.  Irwin will move over water where the Sea Surface Temperature (SST) is near 28°C.  An upper level ridge northwest of Irwin are generating northeastern winds which are blowing toward the top of the circulation.  Those winds are generating moderate vertical wind shear and the shear may be the cause of the asymmetric distribution of showers and thunderstorms.  Tropical Storm Irwin could intensify during the next 24 to 48 hours.

The circulation of Tropical Storm Greg grew in size on Sunday.  However, Tropical Storm Greg will move into a less favorable environment during the next several days.  Tropical Storm Greg is over water where the SST is near 28°C, but it will move over cooler water in a day or two.  Greg could intensify in the short term, but it will weaken by midweek.

Tropical Storm Hilary is moving through a very favorable environment.  Hilary is moving over water where the SST is near 30°C.  The upper level winds are weak and there is little vertical wind shear.  Tropical Storm Hilary could be beginning a period of rapid intensification.  Hilary is forecast to become a hurricane on Monday and it could be a major hurricane later this week.

A subtropical ridge is steering all three tropical storms in a general west-northwesterly direction.  Tropical Storms Greg, Hilary and Irwin are likely to continue to move a little to the north of due west during the next three days.  On its anticipated track Tropical Storm Hilary is expected to remain west of the west coast of Mexico.