Tag Archives: HWISI

Powerful Typhoon Saola Moves Between Taiwan and Luzon

Powerful Typhoon Saola moved between Taiwan and Luzon on Tuesday night. At 11:00 p.m. EDT on Tuesday the center of Typhoon Saola was located at latitude 20.3°N and longitude 120.7°E which put it about 160 miles (260 km) south-southeast of Kaohsiung, Taiwan. Saola was moving toward the west-northwest at 9 m.p.h. (15 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 922 mb.

Typhoon Saola intensified to the threshold of the equivalent of a Category 5 hurricane on the Saffir-Simpson Scale in Tuesday. A circular eye with a diameter of 15 miles (24 km) was at the center of Saola’ circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Saola’s circulation. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

The size of the circulation around Typhoon Saola increased when Saola intensified on Tuesday. Winds to typhoon force extended out 45 miles (75 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 33.3. The Hurricane Size Index (HSI) was 16.2 and the Hurricane Wind Intensity Size Index (HWISI) was 49.5. Typhoon Saola was similar in size and intensity to Hurricane Ian when Ian hit southwest Florida in 2022.

Typhoon Saola will move through an environment favorable for a powerful typhoon during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 29°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. Typhoon Saola could maintain much of its intensity during the next 24 hours unless concentric eyewalls for again. If concentric eyewalls form again, then an eyewall replacement cycle would cause Saola to weaken.

Typhoon Saola will move around the southern side of a high pressure system over China. The high pressure system will steer Saola toward the west-northwest during the next 24 hours. On its anticipated track, Typhoon Saola will move over the South China Sea. Saola could be near Hong Kong later this week.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Haikui was southwest of Iwo To. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Haikui was located at latitude 20.2°N and longitude 135.7°E which put it about 457 miles (755 km) southwest of Iwo To. Haikui was moving toward the northwest at 6 m.p.h. (10 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 990 mb.

Hurricane Idalia Strengthens to Cat. 2

Hurricane Idalia strengthened to Category 2 on the Saffir-Simpson Scale on Tuesday afternoon. At 5:00 p.m. EDT on Tuesday the center of Hurricane Idalia was located at latitude 26.1°N and longitude 84.8°W which put it about 195 miles (310 km) southwest of Tampa, Florida. Idalia was moving toward the north at 16 m.p.h. (26 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 972 mb.

A Hurricane Warning was in effect for the portion of the coast from Indian Pass to the middle of Longboat Key, Florida. The Hurricane Warning included Tampa Bay. A Hurricane Watch was in effect for the portion of the coast from the Mouth of the St. Mary’s River, Florida to South Santee River, South Carolina. The Hurricane Watch included Charleston, South Carolina. A Tropical Storm Warning was in effect for the portion of the coast from Chokoloskee to the middle of Longboat Key, Florida. A Tropical Storm Warning was also in effect for the portion of the coast from Indian Pass to Mexico Beach, Florida. A Tropical Storm Warning was in effect for the Dry Tortugas. A Tropical Storm Warning was in effect for the portion of the coast from Sebastian Inlet, Florida to Surf City, North Carolina. A Tropical Storm Watch was in effect for the Lower Florida Keys west of Seven Mile Bridge. A Tropical Storm Watch was also in effect for the portion of the coast from Surf City, North Carolina to the North Carolina/Virginia border. The Tropical Storm Watch included Pamlico Sound and Albemarle Sound.

Hurricane Idalia intensified steadily during Tuesday afternoon. A circular eye with a diameter of 30 miles (50 km) was at the center of Idalia’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Idalia’s circulation. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Idalia grew larger when Idalia intensified. Winds to hurricane force extended out 25 miles (40 km) from the center of Idalia’s circulation. Winds to tropical storm force extended out 160 miles (260 km) in the eastern side of Hurricane Ida. Winds to tropical storm force extended out 70 miles in the western side of Ida’s circulation. The Hurricane Intensity Index (HII) for Hurricane Ida was 16.5. The Hurricane Size Index (HSI) was 8.0 and the Hurricane Wind Intensity Size Index (HWISI) was 24.5.

Hurricane Idalia will move through an environment that will be favorable for intensification during the next 12 hours. Idalia will be over water where the Sea Surface Temperatures are near 30°C. It will move into a region between an upper level ridge over the Yucatan Peninsula and an upper level trough over the central U.S. The upper level winds are weaker between the ridge and the trough and there will be little vertical wind shear during the next 12 hours. The upper level winds will be stronger when Idalia moves closer to the upper level trough on Wednesday morning. Hurricane Idalia will intensify during the next 12 hours. Idalia could rapidly intensify at times. Hurricane Idalia is likely to strengthen to a major hurricane.

Hurricane Idalia will move around the western end of high pressure system over the western Atlantic Ocean. The high pressure system and the upper level trough over the central U.S. will steer Idalia toward the north-northeast during the next 12 hours. The upper level trough will turn Idalia toward the northeast on Wednesday. On its anticipated track, Hurricane Idalia will likely to make landfall on the coast of the northeast Gulf of Mexico on Wednesday morning. Idalia is likely to make landfall as a major hurricane.

Hurricane Idalia is forecast to be a major hurricane when it reaches the coast of Florida. Idalia could be similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005. Hurricane Idalia is likely to make landfall in an area where high storm surges can occur. Idalia could cause a storm surge of up to 15 feet (4.5 meters) near where the center makes landfall. A Storm Surge Warning has been issued for the portion of the coast from Englewood to Indian Pass, Florida. The Storm Surge Warning includes Tampa Bay. Hurricane Idalia will bring strong winds and heavy rain to parts of central and northern Florida. Idalia will be capable of causing major damage over parts of northern and northeastern Florida. Widespread outages of electricity are likely. Heavy rain could cause flash floods in some locations. Strong winds and heavy rain will spread over eastern Georgia, South Carolina and North Carolina when Idalia moves toward the northeast. Flood Watches are in effect for parts of northern Florida, eastern Georgia, South Carolina and North Carolina.

Elsewhere, Hurricane Franklin was west of Bermuda. At 5:00 p.m. EDT on Tuesday the center of Hurricane Franklin was located at latitude 31.4°N and longitude 69.9°W which put it about 305 miles (490 km) west of Bermuda. Franklin was moving toward the northeast at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 947 mb. A Tropical Storm Warning was in effect for Bermuda.

Typhoon Saola Moves Back Toward Northern Luzon

Typhoon Saola moved back toward northern Luzon on Monday. At 11:00 p.m. EDT on Monday the center of Typhoon Saola was located at latitude 18.8°N and longitude 123.3°E which put it about 115 miles (185 km) east-northeast of Aparri, Philippines. Saola was moving toward the northwest at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 115 m.p.h. (185 km/h) and there were wind gusts to 145 m.p.h. (235 km/h). The minimum surface pressure was 951 mb.

Two concentric eyewalls formed in the core of Typhoon Saola on Monday. A small eye was at the center of Saola’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. A second, slightly larger ring of storms surrounded the inner eyewall. Bands of showers and thunderstorms were revolving around the concentric eyewalls. Storms in the eyewalls generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Saola was small even with the two concentric eyewalls. Winds to typhoon force extended out 25 miles (40 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 115 miles (185 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 20.6. The Hurricane Size Index (HSI) was 9.5 and the Hurricane Wind Intensity Size Index (HWISI) was 30.1. Typhoon Saola was similar in size and intensity to Hurricane Zeta when Zeta hit Louisiana in 2020.

Typhoon Saola will move through an environment favorable for intensification during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. Typhoon Saola could intensify during the next 24 hours.

Typhoon Saola will move around the southwestern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Saola toward the northwest during the next 24 hours. On its anticipated track, Typhoon Saola will move between Luzon and Taiwan in 24 hours.

Typhoon Saola will bring strong winds and heavy rain to the islands north of Luzon. Saola could also drop heavy rains over parts of northern Luzon. Heavy rain is likely to cause flash floods in some locations.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey moved quickly away from Japan and Tropical Storm Haikui formed south of Iwo To. At 11:00 p.m. EDT on Monday the center of Tropical Storm Damrey was located at latitude 41.2°N and longitude 152.3°E which put it about 285 miles (460 km) east-southeast of Hamanaka, Japan. Damrey was moving toward the east at 25 m.p.h. (40 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 990 mb.

At 11:00 p.m. EDT on Monday the center of Tropical Storm Haikui was located at latitude 19.2°N and longitude 137.6°E which put it about 450 miles (725 km) south-southwest of Iwo To. Haikui was moving toward the west-northwest at 17 m.p.h. (28 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 995 mb.

Typhoon Saola Churns East of Luzon

Typhoon Saola continued to churn over the Western North Pacific Ocean east of Luzon on Sunday. At 11:00 p.m. EDT on Sunday the center of Typhoon Saola was located at latitude 17.0°N and longitude 124.4°E which put it about 200 miles (320 km) east-southeast of Aparri, Philippines. Saola was moving toward the northeast at 12 m.p.h. (19 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 160 m.p.h. (260 km/h). The minimum surface pressure was 941 mb.

Microwave satellite images showed that the inner end of a rainband was wrapping around the existing eye and eyewall at the center of Typhoon Saola. If the inner end of the rainband wraps completely around the existing eye and eyewall, then a second, larger outer eyewall would form. The formation of two concentric eyewalls would mark the start of an eyewall replacement cycle. An eyewall replacement cycle would cause Typhoon Saola to weaken.

There was still a small circular eye at the center of Typhoon Saola. The small eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Storms near the center of Saola’s circulation generated upper level divergence that pumped mass away from the typhoon.

The circulation around Typhoon Saola was small. Winds to typhoon force extended out 20 miles (30 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 90 miles (145 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 25.1. The Hurricane Size Index (HSI) was 6.9 and the Hurricane Wind Intensity Size Index (HWISI) was 32.0. Typhoon Saola was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

Typhoon Saola will move through an environment favorable for intensification during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. However, an eyewall replacement cycle is likely to cause Typhoon Saola to weaken during the next 24 hours.

Typhoon Saola will move around the southwestern side of a high pressure system over the Western North Pacific Ocean. The high pressure system will steer Saola back toward the north during the next 24 hours. On its anticipated track, Typhoon Saola will move parallel to the coast of northeastern Luzon. Saola could move toward southern Taiwan later this week.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey was passing east of Japan. At 11:00 p.m. EDT on Sunday the center of Tropical Storm Damrey was located at latitude 38.9°N and longitude 145.3°E which put it about 225 miles (360 km) southeast of Misawa, Japan. Damrey was moving toward the north-northeast at 14 m.p.h. (22 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 979 mb.

Typhoon Saola Strengthens to Equivalent of a Major Hurricane

Typhoon Saola strengthened to the equivalent of a major hurricane over the Western North Pacific Ocean near northern Luzon on Saturday morning. At 5:00 a.m. EDT on Saturday the center of Typhoon Saola was located at latitude 17.8°N and longitude 123.3°E which put it about 100 miles (160 km) east-southeast of Aparri, Philippines. Saola was moving toward the south at 6 m.p.h. (10 km/h). The maximum sustained wind speed was 120 m.p.h. (195 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 953 mb.

Typhoon Saola rapidly intensified to the equivalent of a major hurricane during the past 24 hours. A small circular eye with a diameter of 12 miles (19 km) was at the center of Saola’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Saola. Storms near the core generated strong upper level divergence that pumped large quantities of mass away from the typhoon.

The circulation around Typhoon Saola was small. Winds to typhoon force extended out 30 miles (50 km) from the center of Saola’s circulation. Winds to tropical storm force extended out 80 miles (130 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Saola was 22.1. The Hurricane Size Index (HSI) was 10.9 and the Hurricane Wind Intensity Size Index (HWISI) was 33.0. Typhoon Saola was similar in size and intensity to Hurricane Dennis when Dennis hit Northwest Florida in 2005.

Typhoon Saola will move through an environment favorable for intensification during the next 24 hours. Saola will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level ridge winds are weak and there will be little vertical wind shear. Typhoon Saola is likely to intensify during the next 24 hours.

Typhoon Saola will move around the western side of a large counterclockwise monsoon gyre east of the Philippines. The monsoon gyre will pull Saola toward the southeast during the next 24 hours. A high pressure system over the Western North Pacific Ocean will start to steer Saola back toward the northwest by the end of the weekend. On its anticipated track, Typhoon Saola is forecast to make a slow counterclockwise loop east of Luzon.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Damrey was southeast of Japan. At 5:00 a.m. EDT on Saturday the center of Tropical Storm Damrey was located at latitude 26.9°N and longitude 152.1°E which put it about 1020 miles (1645 km) southeast of Tokyo, Japan. Damrey was moving toward the north-northwest at 25 m.p.h. (40 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 987 mb.

Hurricane Hilary Brings Wind and Rain to Baja California

Hurricane Hilary brought wind and rain to Baja California on Saturday night. At 11:00 p.m. EDT on Saturday the center of Hurricane Hilary was located at latitude 25.3°N and longitude 114.6°W which put it about 175 miles (280 km) south of Punta Eugenia, Mexico. Hilary was moving toward the north-northwest at 18 m.p.h. (30 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 968 mb.

Even though center of Hurricane Hilary was south of Punta Eugenia, Hilary brought strong winds and locally heavy rain to Baja California on Saturday night. A weather station in Loreto, Mexico reported a sustained wind speed of 58 m.p.h. (93 km/h) and a wind gust of 69 m.p.h. (111 km/h). There were reports of flash floods in Santa Rosalia, Mexico.

A Hurricane Warning was in effect for the portion of the coast from Punta Abreojos to Cabo San Quintin, Mexico. A Hurricane Watch was in effect for the portion of the coast from Cabo San Quintin to Ensenada, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Punta Abreojos to Todos Santos, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Los Barriles to Guaymas, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from the U.S. border with Mexico to the Point Mugu, California. The Tropical Storm Warning included San Diego. The Tropical Storm Warning also included Catalina Island. A Tropical Storm Warning was in effect for the portion of the coast from Cabo San Quintin, Mexico to the border with the U.S. A Tropical Storm Watch was in effect for the portion of the coast from Guaymas to Huatabampito, Mexico.

Hurricane Hilary was weakening on Saturday night. There was no longer an eye visible on satellite images of Hurricane Hilary. The distribution of thunderstorms in Hilary was asymmetrical. Many of the thunderstorms were occurring in bands in the northern half of Hilary’s circulation. Bands in the southern half of the circulation consisted primarily of showers and lower clouds.

The circulation around Hurricane Hilary was still large even though Hilary was weakening. Winds to hurricane force extended out 45 miles (75 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 265 miles (425 km) from the center of circulation. The Hurricane Intensity Index (HII) was 13.9. The Hurricane Size Index (HSI) was 18.7 and the Hurricane Wind Intensity Size Index (HWISI) was 32.6. Hurricane Hilary was similar in size and intensity to Hurricane Matthew when Matthew hit South Carolina in 2016.

Hurricane Hilary will be moving into an environment that will be unfavorable for a hurricane during the next 24 hours. Hilary will move over water where the Sea Surface Temperatures are colder than 26°C. It will move between an upper level ridge over Mexico and the south central U.S. and an upper level low west of California. The upper level ridge and upper level low will interact to produce northerly winds that will blow toward the top of Hilary’s circulation. Those winds will cause the vertical wind shear to increase. The combination of cooler water and more vertical wind shear will cause Hurricane Hilary to weaken during the next 24 hours. In addition, much of the circulation in the eastern side of Hurricane Hilary will pass over Baja California. The mountains in Baja California will partially disrupt the flow of air around Hurricane Hilary.

The upper level ridge over the south central U.S. and the upper level low west of California will steer Hurricane Hilary toward the north-northwest during the next 24 hours. On its anticipated track, the center of Hurricane Hilary will be near Punta Eugenia early Sunday morning. Hilary will continue to produce strong, gusty winds and locally heavy rain in Baja California on Sunday. Heavy rain is likely to cause flash floods in some locations.

Hurricane Hilary could take a track similar to the one taken by Hurricane Nora in 1997. The center of Hilary will reach southern California by Sunday evening. Hilary will weaken to a tropical storm before it reaches southern California. Hilary will bring strong winds and locally heavy rain to parts of southern California. The heaviest rain is likely to fall where the wind force the air to rise over mountains. Heavy rain is likely to cause flash floods in some locations. Flood Watches have been issued for parts of southern California, southern Nevada, southern Utah and western Arizona. Hilary could also bring strong winds to mountains in southern Nevada, southern Utah and western Arizona.

Hurricane Hilary Moves Toward Baja California

Hurricane Hilary was moving toward Baja California on Saturday morning. At 8:00 a.m. EDT on Saturday the center of Hurricane Hilary was located at latitude 21.5°N and longitude 113.4°W which put it about 490 miles (790 km) south-southeast of Punta Eugenia, Mexico. Hilary was moving toward the north-northwest at 13 m.p.h. (21 km/h). The maximum sustained wind speed was 130 m.p.h. (210 km/h) and there were wind gusts to 155 m.p.h. (250 km/h). The minimum surface pressure was 943 mb.

A Hurricane Warning was in effect for the portion of the coast from Punta Abreojos to Cabo San Quintin, Mexico. A Hurricane Watch was in effect for the portion of the coast from Cabo San Quintin to Ensenada, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Punta Abreojos to Guaymas, Mexico. The Tropical Storm Warning included Cabo San Lucas. A Tropical Storm Warning was in effect for the portion of the coast from the U.S. border with Mexico to the Point Mugu, California. The Tropical Storm Warning included San Diego. The Tropical Storm Warning also included Catalina Island. A Tropical Storm Warning was in effect for the portion of the coast from Cabo San Quintin, Mexico to the border with the U.S. A Tropical Storm Watch was in effect for the portion of the coast from Guaymas to Huatabampito, Mexico.

Hurricane Hilary was moving closer to Baja California on Saturday morning. An eye with a diameter of 30 miles (50 km) was at the center of Hilary’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Hilary. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Hilary was large. Winds to hurricane force extended out 50 miles (80 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 265 miles (425 km) from the center of circulation. The Hurricane Intensity Index (HII) was 25.1. The Hurricane Size Index (HSI) was 19.2 and the Hurricane Wind Intensity Size Index (HWISI) was 44.3. Hurricane Hilary was capable of causing regional major damage.

Hurricane Hilary appeared to be starting to weaken on Saturday morning. Thunderstorms were weakening in bands in the western side of Hilary’s circulation. Some of the bands in the western part of Hilary consisted primarily of showers and lower clouds. Northerly winds in the western half of Hurricane Hilary were pulling cooler, drier air into that part of the hurricane.

Hurricane Hilary will be moving into an environment that will become unfavorable for a major hurricane during the next 24 hours. Hilary will move over water where the Sea Surface Temperatures are cooler than 27°C. It will move between an upper level ridge over Mexico and the south central U.S. and an upper level low west of California. The upper level ridge and upper level low will interact to produce northerly winds that will blow toward the top of Hilary’s circulation. Those winds will cause the vertical wind shear to increase. The combination of cooler water and more vertical wind shear will cause Hurricane Hilary to weaken during the next 24 hours.

The upper level ridge over the south central U.S. and the upper level low west of California will steer Hurricane Hilary toward the north-northwest during the next 24 hours. On its anticipated track, the center of Hurricane Hilary will approach Punta Eugenia on Saturday night. Hilary will bring strong, gusty winds and locally heavy rain to Baja California. Heavy rain is likely to cause flash floods in some locations.

Hilary will reach southern California on Sunday. Hilary is likely to weaken to a tropical storm before it reaches southern California. Hilary bring strong winds and locally heavy rain to parts of southern California. Heavy rain is likely to cause flash floods in some locations. Flood Watches have been issued for parts of southern California, southern Nevada, southern Utah and western Arizona. Hilary could also bring strong winds to mountains in southern Nevada, southern Utah and western Arizona.

Hilary Prompts Hurricane Warning for Baja, Tropical Storm Watch for Southern California

The potential threat from Hurricane Hilary prompted the issuance of a Hurricane Warning for part of Baja California and a Tropical Storm Watch for Southern California on Friday morning. At 11:00 a.m. EDT on Friday the center of Hurricane Hilary was located at latitude 17.9°N and longitude 111.4°W which put it about 360 miles (575 km) south-southwest of Cabo San Lucas, Mexico. Hilary was moving toward the northwest at 10 m.p.h. (16 km/h). The maximum sustained wind speed was 145 m.p.h. (230 km/h) and there were wind gusts to 170 m.p.h. (280 km/h). The minimum surface pressure was 939 mb.

A Hurricane Warning was in effect for the portion of the coast from Punta Abreojos to Punta Eugenia, Mexico. A Hurricane Watch was in effect for the portion of the coast from Punta Eugenia to Ensenada, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Punta Abreojos to Loreto, Mexico. The Tropical Storm Warning includes Cabo San Lucas. A Tropical Storm Watch was in effect for the portion of the coast from the U.S. border with Mexico to the Orange/Los Angeles County Line. The Tropical Storm Watch included Catalina Island. A Tropical Storm Watch was in effect for the portion of the coast from Ensenada, Mexico to the border with the U.S. A Tropical Storm Watch was in effect for the portion of the coast from Loreto to Huatabampito, Mexico.

Hurricane Hilary continued to intensify on Friday morning. A circular eye with a diameter of 20 miles (30 km) was at the center of Hilary’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Hilary. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Hilary was large. Winds to hurricane force extended out 45 miles (75 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 290 miles (465 km) from the center of circulation. The Hurricane Intensity Index (HII) was 29.9. The Hurricane Size Index (HSI) was 16.9 and the Hurricane Wind Intensity Size Index (HWISI) was 46.8. Hurricane Hilary was similar in size and intensity to Hurricane Ida when Ida hit Louisiana in 2021.

Hurricane Hilary will move through an environment favorable for a major hurricane during the next 24 hours. Hilary will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Hilary could intensify during the next 24 hours. However, if the inner end of a rainband wraps around the existing eye and eyewall, then concentric eyewalls could form. If concentric eyewalls form, then an eyewall replacement cycle could cause Hilary to weaken.

Hurricane Hilary will move around the western part of a high pressure system over Mexico and the south central U.S. The high pressure system will steer Hilary toward the north-northwest during the next 24 hours. On its anticipated track Hurricane Hilary will move toward Baja California. Hilary will move more toward the north when it reaches the western end of the high pressure system during the weekend. The center of Hurricane Hilary will be near Punta Eugenia on Sunday morning. Hurricane Hilary will start to affect Baja California on Saturday. Hilary will bring strong, gusty winds and locally heavy rain to Baja California. Heavy rain is likely to cause flash floods in some locations.

The center of Hurricane Hilary is likely to approach southern California on Sunday night. There is cooler water west of the northern part of Baja California. Hilary will be weakening when it approaches southern California. Hilary bring strong winds and locally heavy rain to parts of southern California. Heavy rain is likely to cause flash floods in some locations. Flood Watches have been issued for parts of southern California, southern Nevada, southern Utah and western Arizona.

Hilary Rapidly Intensifies to a Major Hurricane

Hurricane Hilary rapidly intensified to a major hurricane over the Eastern North Pacific Ocean on Thursday evening. At 11:00 p.m. EDT on Thursday the center of Hurricane Hilary was located at latitude 16.7°N and longitude 110.0°W which put it about 430 miles (690 km) south of Cabo San Lucas, Mexico. Hilary was moving toward the west-northwest at 14 m.p.h. (22 km/h). The maximum sustained wind speed was 125 m.p.h. (200 km/h) and there were wind gusts to 150 m.p.h. (240 km/h). The minimum surface pressure was 952 mb.

A Hurricane Watch was in effect for the portion of the coast from Punta Eugenia to Punta Abreojos, Mexico. A Tropical Storm Warning was in effect for the portion of the coast from Cabo San Lazaro to Los Barriles, Mexico. The Tropical Storm Warning included Cabo San Lucas. Tropical Storm Watches were in effect for the portions of the coast from Cabo San Lazaro to Punta Eugenia, Mexico and from Los Barriles to Bahia San Juan Bautista, Mexico.

Hurricane Hilary rapidly intensified to a major hurricane on Thursday. An eye with a diameter of 23 miles (37 km) was at the center of Hilary’s circulation. The eye was surrounded by a ring of thunderstorms and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Hurricane Hilary. Storms near the core generated upper level divergence that pumped mass away from the hurricane.

The circulation around Hurricane Hilary was large. Winds to hurricane force extended out 60 miles (95 km) from the center of Hilary’s circulation. Winds to tropical storm force extended out 290 miles (465 km) from the center of circulation. The Hurricane Intensity Index (HII) was 23.6. The Hurricane Size Index (HSI) was 20.3 and the Hurricane Wind Intensity Size Index (HWISI) was 43.9.

Hurricane Hilary will move through an environment favorable for intensification during the next 24 hours. Hilary will move over water where the Sea Surface Temperatures are near 30°C. It will move through a region where the upper level winds are weak and there will be little vertical wind shear. Hurricane Hilary is likely to continue to intensify during the next 24 hours. Hilary could intensify rapidly at times on Friday.

Hurricane Hilary will move around the western part of a high pressure system over Mexico. The high pressure system will steer Hilary toward the northwest during the next 24 hours. On its anticipated track Hurricane Hilary will move toward Baja California. Hilary will move more toward the north when it reaches the western end of the high pressure system during the weekend. Hurricane Hilary will start to affect Baja California during the weekend.

Elsewhere, former Tropical Storm Greg and former Tropical Storm Fernanda both weakened to tropical depressions. At 11:00 p.m. EDT on Thursday the center of Tropical Depression Greg was located at latitude 12.0°N and longitude 158.5°W which put it about 645 miles (1035 km) south of Honolulu, Hawaii. Greg was moving toward the west at 17 m.p.h. (28 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1007 mb.

At 11:00 p.m. EDT on Thursday the center of Tropical Depression Fernanda was located at latitude 16.4°N and longitude 133.8°W which put it about 1615 miles (2605 km) west-southwest of the southern tip of Baja California. Fernanda was moving toward the west at 15 m.p.h. (24 km/h). The maximum sustained wind speed was 35 m.p.h. (55 km/h) and there were wind gusts to 45 m.p.h. (75 km/h). The minimum surface pressure was 1005 mb.

Typhoon Lan Makes Landfall in Honshu

Typhoon Lan made landfall in Honshu on Monday. At 5:00 p.m. EDT on Monday the center of Typhoon Lan was located at latitude 33.7°N and longitude 135.9°E which put it about 15 miles (25 km) north of Shingu, Japan. Lan was moving toward the northwest 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 115 m.p.h. (185 km/h). The minimum surface pressure was 970 mb.

The center of Typhoon Lan made landfall in Wakayama Prefecture near Shingu on Monday. A circular eye with a diameter of 50 miles (80 km) was at the center of Lan’s circulation. A broken ring of thunderstorms surrounded the eye and the strongest winds were occurring in that ring of storms. Bands of showers and thunderstorms were revolving around the core of Typhoon Lan.

There was still a large circulation around Typhoon Lan. Winds to typhoon force extended out 70 miles (110 km) from the center of Lan’s circulation. Winds to tropical storm force extended out 145 miles (235 km) from the center of circulation. The Hurricane Intensity Index (HII) for Typhoon Lan was 13.9. The Hurricane Size Index (HSI) was 23.0 and the Hurricane Wind Intensity Size Index (HWISI) was 36.9. Typhoon Lan was capable of causing widespread serious damage.

Typhoon Lan will move around the western part of a high pressure system over the Western North Pacific Ocean during the next 24 hours. The high pressure system will steer Lan toward the north-northwest during the next 24 hours. On its anticipated track, Typhoon Lan will move across Honshu during the next 24 hours. The center of Lan’s circulation will pass near Osaka in a few hours. The center of circulation will also pass west of Kyoto before Lan moves over the Sea of Japan.

Although Typhoon Lan will weaken as it moves across Honshu, Lan will produce strong gusty winds and locally heavy rain over parts of Honshu. Lan will drop heavy rain over Wakayama, Nara, Osaka, Shiga, Kyoto, Hyogo, Tottori, Okayama and Fukui Prefectures. Heavy rain could cause flash floods in some locations. Wind and rain are also likely to cause loss of electricity in widespread areas.

Elsewhere over the Western North Pacific Ocean, Tropical Storm Dora continued to weaken east of Wake Island. At 5:00 p.m. EDT on Monday the center of Tropical Storm Dora was located at latitude 20.9°N and longitude 168.3°E which put it about 145 miles (235 km) east of Wake Island. Dora was moving toward the north-northwest at 11 m.p.h. (17 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.