Monthly Archives: August 2017

Category 4 Hurricane Harvey Makes Landfall in Texas

Category 4 Hurricane Harvey made landfall near Rockport, Texas on Friday night.  Harvey was the first Category 4 hurricane on the Saffir-Simpson Scale to officially make landfall in Texas since Hurricane Carla in 1961.  Harvey was the first Category 4 hurricane to officially make landfall in the U.S. since Hurricane Charley in 2004.  At 11:00 p.m. EDT on Friday the center of Hurricane Harvey was located at latitude 28.0°N and longitude 97.0°W which put it about 30 miles (50 km) east-northeast of Corpus Christi, Texas.  Harvey was moving toward the northwest at 7 m.p.h. (11 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).  The minimum surface pressure was 938 mb.

The center of the eye of Hurricane Harvey moved across San Jose Island and it officially made landfall near Rockport, Texas.  The powerful western side of the eyewall moved over Corpus Christi Bay, Port Aransas, Ingleside and Rockport.  Those areas experienced winds of over 100 m.p.h. (160 km/h).  The eye was over Aransas Bay and the winds were weaker in Rockport.  The wind speeds will increase again when the eastern part of the eyewall reaches those locations.  Bands of winds to tropical storm force were revolving inland outside the core of Hurricane Harvey.  Winds to hurricane force extended out about 40 miles (65 km) from the center of circulation.  Winds to tropical storm force extended out about 140 miles (225 km) from the center.

The Hurricane Intensity Index (HII) for Hurricane Harvey at landfall was 25.1.  The Hurricane Size Index (HSI) was 11.9 and the Hurricane Wind Intensity Size Index (HWISI) was 37.0.  The indices indicate that Hurricane Harvey is capable of producing regional extensive damage. In terms of wind speed and size Hurricane Harvey is similar to Hurricane Charley.  The HII for Charley when in made landfall in southwest Florida in 2004 was 29.9.  The HSI was 8.1 and the HWISI for Charley was 38.0.  Harvey is not quite as strong as Charley was, but Harvey is a little larger.  So, Hurricane Harvey has approximately the same potential to cause damage that Hurricane Charley had.

Hurricane Harvey completed an eyewall replacement cycle a few hours before it made landfall.  the timing of the eyewall replacement cycle meant that Hurricane Harvey had time to intensify to Category 4 before it reached the Texas coast.  The eye contracted and the wind speed increased right up until Hurricane Harvey made landfall.  Hurricane Harvey was at its maximum intensity when it made landfall.

Hurricane Harvey slowed down as it reached the coast and areas near the core of the hurricane are experiencing prolonged periods of high wind speeds.  The prolonged period of high winds will increase the damage caused by those winds.  The winds north of the center of circulation are driving the water toward the coast and a storm surge of 12 feet (4 meters) is possible in some locations.  Hurricane Harvey could stall or make a slow loop during the next several days.  In either case, Hurricane Harvey will drop very heavy rain in some places and fresh water flooding is a serious risk.

Major Hurricane Harvey Closing in on Texas Coast

Major Hurricane Harvey was closing on the Texas coast on Friday afternoon.  At 4:00 p.m. EDT on Friday the center of Hurricane Harvey was located at latitude 27.4°N and longitude 96.4°W which put it about 70 miles (110 km) east-southeast of Corpus Christi, Texas.  Harvey was moving toward the northwest at 10 m.p.h. (16 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 943 mb.

A Hurricane Warning was in effect for the portion of the coast from Port Mansfield to Sargent, Texas.  A Tropical Storm Warning was in effect for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield and from Sargent to High Island, Texas.  A Tropical Storm Watch was in effect from Boca De Catan, Mexico to the mouth of the Rio Grande River.

Hurricane Harvey has a relatively compact circulation.  Winds to hurricane force extend out about 35 miles (55 km) from the center of circulation.  Winds to tropical storm force extend out about 140 miles (225 km) from the center.  The current Hurricane Intensity Index (HII) for Harvey is 22.1.  The Hurricane Size Index (HSI) is 10.4 and the Hurricane Wind Intensity Size Index (HWISI) is 32.5.

Hurricane Harvey went through an eyewall replacement cycle earlier today.  A second outer eyewall encircled the original inner eyewall.  The two concentric eyewalls temporarily interrupted the intensification of Harvey.  Most of the air began converging in the outer eyewall and the inner eyewall dissipated.  The eyewall replacement cycle resulted in Harvey becoming a slightly larger hurricane.  After the inner eyewall dissipated, the remaining outer eyewall began to contract and Harvey started to intensify again.

Hurricane Harvey will still be over the warm water of the western Gulf of Mexico for a few more hours.  So, it does have a chance to intensify further.  There is about a 25% chance that Harvey intensifies to Category 4 on the Saffir-Simpson Scale before it makes landfall.

Harvey is being steered toward the northwest by a subtropical ridge located northeast of the hurricane.  On its anticipated track Hurricane Harvey will most likely make landfall on the coast of Texas between Corpus Christi and Freeport in a few hours.  The steering currents are forecast to weaken about the time Harvey makes landfall and it could meander near the coast of Texas during the weekend.  The track forecast becomes very uncertain at that time.  Some models forecast that Harvey will stall inland, while other models predict it will drift back over the Gulf of Mexico.

Based on current projections the forecast Hurricane Intensity Index (HII) for Harvey at landfall is 26.7.  The forecast Hurricane Size Index (HSI) is 11.6 and the forecast Hurricane Wind Intensity Size Index (HWISI) at landfall is 38.3.  Those indices indicate that Harvey could cause regional major damage in Texas.  Harvey will be stronger, but smaller, than Hurricane Ike was when Ike made landfall in Texas in 2008.  The HII for Ike was 19.2, the HSI was 22.5 and the HWISI was 41.7.  Hurricane Harvey is going to be more similar to Hurricane Charley when Charley made landfall in southwest Florida in 2004.  The HII for Charley was 29.9, the HSI was 8.1 and the HWISI was 38.0

Harvey will bring strong damaging winds to Texas.  Harvey will also cause a dangerous storm surge at the coast.  The storm surge could approach 12 feet (4 meters) in some locations.  Harvey will also drop very heavy rain, if it stalls after it moves inland.  Serious fresh water flooding is possible under that scenario.  The strong winds and flooding could also lead to widespread losses of electricity.

Hurricane Harvey Moves Closer to Texas

Hurricane Harvey moved closer to Texas on Thursday night.  At 11:00 p.m. EDT on Thursday the center of Hurricane Harvey was located at latitude 25.2°N and longitude 94.6°W which put it about 250 miles (400 km) southeast of Corpus Christi, Texas.  Harvey was moving toward the northwest at 10 m.p.h. (16 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 973 mb.

A Hurricane Warning was in effect for the portion of the coast from Port Mansfield to Sargent, Texas.  A Hurricane Watch was in effect from the mouth of the Rio Grande River to Port Mansfield.  A Tropical Storm Warning was in effect for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield and from Sargent to High Island, Texas.  A Tropical Storm Watch was in effect from Boca De Catan, Mexico to the mouth of the Rio Grande River.

Hurricane Harvey intensified rapidly for much of Thursday, but the wind speed stopped increasing Thursday evening.  The interruption of the intensification is probably only temporary.  The minimum surface pressure has continued to decrease slowly, but steadily throughout the evening.  An eye with a diameter of 18 miles (29 km) has appeared intermittently.  Although there was a continuous ring of strong thunderstorms around the eye earlier this afternoon, there has been a break in that ring this evening.  It seems as if there are strong thunderstorms at the leading edge of the primary rainband and downdrafts from those storms may be interfering with the eyewall.  The interference with the eyewall may have temporarily paused the intensification of Hurricane Harvey.

Hurricane Harvey is a small hurricane.  Winds to hurricane force extend out about 25 miles from the center, primarily in the northeastern quadrant of the circulation.  Winds to tropical storm force extend out about 105 miles (170 km) from the center.  The current Hurricane Intensity Index (HII) for Harvey is 12.7.  The Hurricane Size Index (HSI) is 6.6 and the Hurricane Wind Intensity Size Index (HWISI) is 19.3.

Hurricane Harvey will move through a very favorable environment on Friday.  Harvey will move over water where the Sea Surface Temperature is near 31°C.  The upper level winds are weak and there is little vertical wind shear.  Hurricane Harvey is likely to strengthen on Friday and it could intensify rapidly again.  Harvey is likely to be a major hurricane by the time it makes landfall on the Texas coast and it has a chance to get to Category 4 on the Saffir-Simpson Scale.

Harvey is being steered toward the northwest by a subtropical ridge located northeast of the hurricane.  A general northwesterly motion is expected to continue on Friday.  On its anticipated track Hurricane Harvey would make landfall on the coast of Texas near Corpus Christi in about 36 hours.  The steering currents are forecast to weaken about the time Harvey makes landfall and it could meander near the coast of Texas during the weekend.  The track forecast becomes very uncertain at that time.

Based on current projections the forecast Hurricane Intensity Index (HII) for Harvey at landfall is 25.5.  The forecast Hurricane Size Index (HSI) is 16.0 and the forecast Hurricane Wind Intensity Size Index (HWISI) at landfall is 41.5.  Those indices indicate that Harvey could cause regional major damage in Texas.  Harvey would be stronger, but smaller, than Hurricane Ike was when Ike made landfall in Texas in 2008.  The HII for Ike was 19.2, the HSI was 22.5 and the HWISI was 41.7.

Harvey will bring strong damaging winds to Texas.  Harvey will also cause a dangerous storm surge at the coast.  The storm surge could approach 12 feet (4 meters) in some locations.  Harvey will also drop very heavy rain, if it stalls after it moves inland.  Serious fresh water flooding is possible under that scenario.  The strong winds and flooding could also lead to widespread losses of electricity.

Tropical Storm Pakhar Forms East of Luzon

Tropical Storm Pakhar formed east of Luzon on Thursday.  At 5:00 p.m. EDT on Thursday the center of Tropical Storm Pakhar was located at latitude 15.2°N and longitude 124.7°E which put it about 280 miles (455 km) east of Manila, Philippines.  Pakhar was moving toward the west at 13 m.p.h. (21 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.

A center of circulation developed on the eastern edge of a cluster of thunderstorms east of Luzon on Thursday and the Japan Meteorological Agency designated the system as Tropical Storm Pakhar.  The circulation of Pakhar is still in the early organizational stages.  Most of the showers and thunderstorms are occurring west of the center of circulation.  An upper level ridge north of Pakhar is producing easterly winds which are blowing across the circulation.  Those easterly winds are probably responsible for the asymmetrical distribution of thunderstorms on the western side of the tropical storm.

Tropical Storm Pakhar will move through an environment that will be somewhat favorable for intensification during the next 12 to 18 hours.  Pakhar will move over water where the Sea Surface Temperature (SST) is near 30°C.  The easterly winds in the upper levels are causing moderate vertical wind shear and the shear will inhibit intensification.  Tropical Storm Pakhar will weaken when it moves across Luzon.  After Pakhar moves out over the South China Sea, it will move back over water where the SST is near 30°C.  The forecast suggests that there could be less vertical wind shear at that time and Pakhar has a chance to intensify into a typhoon when it moves away from the Philippines.

Pakhar is being steered westward by a subtropical ridge north of the tropical storm.  Pakhar is forecast to turn more toward the northwest when it crosses Luzon.  On its anticipated track Tropical Storm Pakhar will reach the coast of Luzon near Baler in 12 to 18 hours.  Pakhar is forecast to continue moving toward the northwest and it could make another landfall in China west of Hong Kong in about three days.  However, there is more uncertainty about the future track of Pakhar after the tropical storm exits Luzon.

Tropical Storm Pakhar could bring heavy rain to Luzon and cause flooding in some locations.  If Tropical Storm Pakhar intensifies over the South China Sea and makes landfall west of Hong Kong as a typhoon, it could seriously affect the efforts to recover from damage caused by Typhoon Hato which hit that same area a few days ago.

Tropical Storm Harvey Intensifying Rapidly, Hurricane Warning for Texas

Tropical Storm Harvey was intensifying rapidly on Thursday morning and a Hurricane Warning was issued portions of the coast of Texas.  At 11:00 a.m. EDT on Thursday the center of Tropical Storm Harvey was located at latitude 24.0°N and longitude 93.3°W which put it about 365 miles southeast of Corpus Christi, Texas.  Harvey was moving toward the north-northwest at 10 m.p.h. (16 km/h).  The maximum sustained wind speed was 65 m.p.h. (105 km/h) and there were wind gusts to 80 m.p.h. (130 km/h).  The minimum surface pressure was 982 mb.

A Hurricane Warning was in effect for the portion of the coast from Port Mansfield to Matagorda, Texas.  A Hurricane Watch was in effect for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield.  A Tropical Storm Warning was in effect for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield and from Matagorda to High Island, Texas.  A Tropical Storm Watch was in effect for the portion of the coast from Boca De Catan, Mexico to the mouth of the Rio Grande River.

Tropical Storm Harvey intensified very rapidly on Thursday morning.  An eye with a diameter of 18 miles (29 km) formed at the center of circulation.  The eye was surrounded by a ring of very strong thunderstorms.  Additional bands of strong thunderstorms were revolving around the core of Tropical Storm Harvey.  The thunderstorms were generating very strong upper level divergence which was pumping away large amounts of mass in all directions from the tropical storm.  The strong upper level divergence was causing the surface pressure to decrease rapidly.  The minimum surface pressure decreased from 1002 mb to 982 mb in 12 hours.  The rapid decrease in pressure was increasing the pressure gradient force and the winds speeds were increasing accordingly.

Tropical Storm Harvey is in an almost perfect environment for rapid intensification.  Harvey is moving over water where the Sea Surface Temperature is near 31°C.  The upper level winds are very weak and there is almost no vertical wind shear.  Tropical Storm Harvey should continue to intensify rapidly for another 24 to 36 hours.  Harvey will become a hurricane later today and it will likely become a major hurricane before it makes landfall.  Tropical Storm Harvey has the potential to intensify to a Category 4 hurricane on the Saffir-Simpson Scale.

Harvey is being steered toward the north-northwest by a subtropical ridge to the east of the tropical storm.  A general northwesterly motion is forecast continue for another 36 to 48 hours.  On its anticipated track the center of Harvey will approach the coast of Texas on Friday night.  The steering currents are forecast to weaken as Harvey nears the coast.  Some models are forecasting that Harvey drifts slowly toward the west.  Other models stall Harvey and then turn it northeastward.  There is a large degree of uncertainty about the future track of Harvey after it nears the coast.

Based on current projections the forecast Hurricane Intensity Index (HII) for Harvey at landfall is 22.1.  The forecast Hurricane Size Index (HSI) is 18.0 and the forecast Hurricane Wind Intensity Size Index (HWISI) at landfall is 40.1  Those indices indicate that Harvey could cause regional major damage in Texas.  The indices may be conservative if Harvey continues to intensify rapidly up until it makes landfall.  Harvey would be stronger, but a little smaller, than Hurricane Ike was when Ike made landfall in Texas in 2008.  The HII for Ike was 19.2, the HSI was 22.5 and the HWISI was 41.7.

Harvey will bring strong damaging winds to Texas.  Harvey will also cause a dangerous storm surge at the coast.  The storm surge could approach 12 feet (4 meters) in some locations.  Harvey will also drop very heavy rain, if it stalls after it moves inland.  Serious fresh water flooding is possible under that scenario.

Tropical Depression Harvey Redevelops Southeast of Texas

A tropical depression redeveloped southeast of Texas from the remnants of former Tropical Storm Harvey on Wednesday morning.  The National Hurricane Center (NHC) began issuing advisories on Tropical Depression Harvey again.  At 11:00 a.m. EDT on Wednesday the center of Tropical Depression Harvey was located at latitude 21.5°N and longitude 92.5°W which put it about 535 miles (860 km) southeast of Port O’Connor, Texas.  Harvey was moving toward the northwest at 9 m.p.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 Hurricane Watch was issued for the portion of the coast from Port Mansfield to San Luis Pass, Texas.  A Tropical Storm Watch was issued for the portion of the coast from the mouth of the Rio Grande River to Port Mansfield and from San Luis Pass to High Island, Texas.  NHC also issued a Storm Surge Watch for the portion of the coast from Port Mansfield to High Island.

A reconnaissance aircraft found that a distinct low level center had formed in the remnants of Tropical Storm Harvey on Wednesday morning.  The circulation in Tropical Depression Harvey was still in the process of organizing.  Stronger thunderstorms were forming near the center of circulation.  Additional bands of showers and thunderstorms were forming outside the core of the circulation.  The distribution of showers and thunderstorms was somewhat asymmetrical.  There were more showers and thunderstorms in the eastern half of the circulation.  Although there were fewer showers and thunderstorms in the western half of the circulation, more storms were developing in that part of Tropical Depression Harvey.  The thunderstorms near the core were beginning to generate upper level divergence which was pumping away mass to the northeast of the tropical depression.

Tropical Depression Harvey will move through an environment that will become increasing favorable for intensification.  Harvey will move over water where the Sea Surface Temperature is near 30°C.  An upper level low near the coast of Louisiana is causing some vertical wind shear.  However, the low is forecast to move north and weaken and the shear is forecast to decrease.  Tropical Depression Harvey may strengthen slowly at first while the circulation is organizing.  The rate of intensification will likely increase on Thursday and there could be a period of rapid intensification when the Harvey near hurricane intensity.

Tropical Depression Harvey is moving around the western end of a subtropical high pressure system which is steering Harvey toward the northwest.  Harvey is forecast to continue to move toward the northwest and it will approach Texas in about 48 hours.  The winds are the steering level are forecast to weaken when Harvey approaches Texas and it could move more slowly as it nears the coast.

Tropical Depression Harvey could evolve into a very dangerous storm.  The coast along the western Gulf of Mexico is very susceptible to storm surges.  An intensifying, slow moving hurricane could generate dangerous storm surges along the coast.  If Harvey stalls after it moves inland, it could drop very heavy rain and there is also the potential for dangerous fresh water flooding.

Typhoon Hato Brings Wind and Rain to Hong Kong

Typhoon Hato brought wind and rain to Hong Kong as the eye moved just south of the city.  At 11:00 p.m. EDT on Tuesday the center of Typhoon Hato was located at latitude 21.8°N and longitude 113.8°E which put it about 60 miles (95 km) south-southeast of Hong Kong.  Hato was moving toward the west-northwest at 18 m.p.h. (29 km/h).  The maximum sustained wind speed was 105 m.p.h. (170 km/h) and there were wind gusts to 130 m.p.h. (210 km/h).  The minimum surface pressure was 963 mb.

Typhoon Hato intensified rapidly as it approached Hong Kong.  A circular eye with a diameter of 50 miles (80 km) developed at the center of Hato.  The eye was surrounded by a thick ring of strong thunderstorms and the strongest winds were occurring in that ring.  Additional bands of showers and thunderstorms were revolving around the core of Hato.  The size of the circulation around Typhoon Hato also increased significantly.  Winds to typhoon force extended out about 50 miles (80 km) from the center of circulation.  Winds to tropical storm force extended out about 175 miles (280 km) from the center.

The Hurricane Intensity Index (HII) was 17.8.  The Hurricane Size Index (HSI) was 16.9 and the Hurricane Wind Intensity Size Index (HWISI) was 38.7.  Those indices indicate that Typhoon Hato is capable of producing serious regional wind damage.  Typhoon Hato could cause a storm surge of 6 to 9 feet (2 to 3 meters) along the coast.  Hato will also drop heavy rain over parts of China and flash floods could occur in some areas.

Typhoon Hato is being steered toward the west-northwest by a subtropical ridge northeast of the typhoon and that general motion is forecast to continue.  On its anticipated track the center of Typhoon Hato will make landfall west of Hong Kong in a few hours.  Hato will continue to move inland over southeastern China.   Typhoon Hato will weaken as it moves inland, but it could drop locally heavy rain over parts of Zizhiqu, Huangzu and Guangxi provinces.

Remnants of Tropical Storm Harvey About to Move Over Gulf of Mexico

The remnants of former Tropical Storm Harvey are about to move over the southern Gulf of Mexico.  At 2:00 p.m. EDT on Tuesday the center of the remnants of Tropical Storm Harvey was located at latitude 20.3°N and longitude 89.8°W which put it about 45 miles (75 km) south-southwest of Merida, Mexico.  It was moving toward the northwest at 15 m.p.h.  The maximum sustained wind speed was 30 m.p.h. (50 km/h) and there were wind gusts to 40 m.p.h. (65 km/h).  The minimum surface pressure was 1010 mb.

A broad area of low pressure that contained the remnants of former Tropical Storm Harvey moved across the Yucatan peninsula on Tuesday.  Thin bands of showers were rotating around the broad area of low pressure over land.  Several broken bands of thunderstorms were evident on the northern and northeastern periphery of the low pressure system.  There were several smaller centers rotating around inside the larger area of low pressure, but the circulation appeared to consolidating around a center near Merida.  A few thunderstorms were forming near that center as it neared the coast.

The National Hurricane Center indicated that there is a nearly 100% chance that the low pressure system will strengthen into a tropical cyclone again once it moves over the Gulf of Mexico.  The Sea Surface Temperature (SST) in the southern Gulf of Mexico is near 31°C.  An upper level low over the northwestern Gulf of Mexico was producing some vertical shear over the top of the surface low.  The upper low is forecast to move north and weaken.  An upper level ridge over the northwestern Caribbean Sea is forecast to move over the western Gulf of Mexico.  The upper ridge will produce southerly winds which will cause some vertical wind shear.  However, those winds are expected to be weak enough to allow for intensification.  The southerly winds could actually enhance upper level divergence to the north of the low pressure system in a day or two.

Given the large size of the low pressure system and the lack of a well defined center of circulation, the system will likely start to intensify slowly.  The rate of intensification will increase once a well defined center forms.  A period of very rapid intensification could occur later this week because of very warm SSTs and little vertical wind shear.  The area of low pressure could become a tropical depression within 12 hours.  It is likely to be a tropical storm on Wednesday.  The system has a good chance of becoming a hurricane over the western Gulf of Mexico.  If the system moves slowly and rapid intensification occurs, it could become a major hurricane.

A ridge in the middle troposphere near Florida is steering the low pressure system toward the northwest and a general northwesterly motion is forecast for the next several days.  There will be more uncertainty about the future track until a well developed center of circulation forms.  However, it seems likely that this system will move toward the coast of Texas.  The system could slow and/or turn more toward the north when it nears the coast.  It has the potential to become a significant hurricane by the time it reaches the coast.  It could bring strong gusty winds, which could cause a significant storm surge at the coast.  If the system moves slowly, it could also drop very heavy rain, which would create flash floods.

Strengthening Typhoon Hato Nears China

Typhoon Hato strengthened to a typhoon as it moved closer to a landfall on the coast of China.  At 11:00 a.m. EDT on Tuesday the center of Typhoon Hato was located at latitude 20.9°N and longitude 116.6°E which put it about 225 miles (365 km) east-southeast of Hong Kong.  Hato was moving toward the west-northwest at 15 m.p.h. (24 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. (150 km/h).  The minimum surface pressure was 978 mb.

The organization of Typhoon Hato improved significantly in recent hours.  A circular eye developed at the center of circulation.  A ring of strong thunderstorms formed around the eye.  The strongest winds were occurring in the ring of storms around the eye.  Additional bands of showers and thunderstorms developed south and east of the center.   There were fewer showers and thunderstorms north and west of the center of circulation.  Thunderstorms in the core of Hato were generating strong upper level divergence which was pumping mass away to the south and east of the typhoon.  Hato is a fairly small typhoon.  Winds to typhoon force extend out about 20 miles (32 km) from the center of circulation.  Winds to tropical storm force extend out about 145 miles (230 km) from the center.

The Hurricane Intensity Index (HII) for Typhoon Hato is 10.4.  The Hurricane Size Index (HSI) is 8.3 and the Hurricane Wind Intensity Size Index (HWISI) is 18.7.

Typhoon Hato will move through an environment favorable for intensification until it makes landfall in China.  Hato will move over water where the Sea Surface Temperature is near 31°C.  An upper level ridge over China is producing easterly winds which are blowing toward the top of the circulation.  The strongest winds are north of Typhoon Hato and the vertical wind shear is moderate.  The shear could slow the rate of intensification, but it is not likely to prevent further intensification.

Typhoon Hato is being steered to the west-northwest by a subtropical ridge to the north of the typhoon and that general motion is expected to continue.  On its anticipated track Typhoon Hato will make landfall near Hong Kong in 12 to 18 hours.  Typhoon Hato will bring strong gusty winds and locally heavy rain to parts of eastern China.  Heavy rain could produce flash floods in some locations.  Hato will also generate a storm surge along the coast.

Kenneth Rapidly Intensifies Into a Hurricane

One time Tropical Storm Kenneth rapidly intensified into a hurricane on Sunday.  At 5:00 p.m. EDT on Sunday the center of Hurricane Kenneth was located at latitude 16.2°N and longitude 128.4°W which put it about 1290 miles (2075 km) west-southwest of the southern tip of Baja California.  Kenneth was moving toward the west at 14 m.p.h. (22 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 980 mb.

The structure of Hurricane Kenneth improved significantly during the past few hours.  A small circular eye emerged at the center of circulation.  A ring of strong thunderstorms surrounded the eye and the strongest winds are occurring in this ring of thunderstorms.  Additional bands of showers and thunderstorms intensified south and east of the center.  Thunderstorms near the core of Kenneth were generating strong upper level divergence which was pumping mass away from the hurricane.

Hurricane Kenneth will continue to move through an environment favorable for intensification on Monday.  Kenneth will move over water where the Sea Surface Temperature (SST) is near 28.5°C.  Hurricane Kenneth is moving through a region where the winds in the upper levels are weak and there is not much vertical wind shear.  Hurricane Kenneth could continue to intensify for another 12 to 24 hours.  The speed of the upper level winds could increase in a day or so, and more vertical wind shear would inhibit intensification.  Eventually Hurricane Kenneth will move over cooler SSTs and start to weaken.

Kenneth if moving south of a subtropical ridge which is steering the hurricane toward the west.  The ridge is forecast to continue to steer Kenneth westward for another 12 to 24 hours.  Hurricane Kenneth will turn toward the north when it reaches the western end of the ridge.  On its anticipated track Hurricane Kenneth would pose no direct threat to land.