Monthly Archives: June 2021

Tropical Storm Choi-wan Moves Toward Taiwan

Tropical Storm Choi-wan moved toward Taiwan on Thursday. At 5:00 p.m. EDT on Thursday the center of Tropical Storm Choi-wan was located at latitude 20.0°N and longitude 118.9°E which put it about 185 miles (300 km) south-southwest of Taiwan. Choi-wan was moving toward the north-northeast at 10 m.p.h. (16 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 1002 mb.

Tropical Storm Choi-wan turned toward the north-northeast on Thursday which put it on a track towards southern Taiwan. The distribution of thunderstorms around Choi-wan was asymmetrical. The strongest thunderstorms were occurring in bands in the southwestern quadrant of Tropical Storm Choi-wan. Bands in the other quadrants of Choi-wan consisted primarily of showers and lower clouds. The distribution of wind speeds around Tropical Storm Choi-wan was also asymmetrical. Winds to tropical storm force extended out 125 miles (200 km) on the western side of Choi-wan. Winds to tropical storm force only extended out 65 miles (105 km) on the eastern side of the circulation.

Tropical Storm Choi-wan will move through an area that is mostly unfavorable for intensification during the next 36 hours. The center of Choi-wan will move over an area where the Sea Surface Temperatures are near 30°C. However, an upper level ridge centered over southern China will produce moderate northeasterly winds that will blow toward the top of the tropical storm. Those winds will cause moderate vertical wind shear and they are already responsible for the asymmetrical distribution of thunderstorms. The moderate vertical wind shear will likely prevent intensification of Tropical Storm Choi-wan.

Tropical Storm Choi-wan will move around the northwestern part of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Choi-wan toward the north-northeast during the next 24 hours. On its anticipated track the center of Tropical Storm Choi-wan will reach southern Taiwan in 12 hours. Choi-wan could drop locally heavy rain over parts of southern Taiwan. Flash floods could occur in some locations. Tropical Storm Choi-wan could approach the southern Ryuku Islands in 24 hours. Choi-wan could bring a period of gusty winds to southern Taiwan and the southern Ryukyu Islands.

Tropical Storm Choi-wan Drops Rain on Luzon

Tropical Storm Choi-wan dropped rain on parts of Luzon around Manila on Wednesday. At 5:00 p.m. EDT on Wednesday the center of Tropical Storm Choi-wan was located at latitude 15.5°N and longitude 119.6°E which put it about 85 miles (135 km) west-northwest of Manila, Philippines. Choi-wan was moving toward the northwest at 16 m.p.h. (26 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 1002 mb.

The center of Tropical Storm Choi-wan passed just south of Manila before the tropical storm moved west of Luzon. Bands near the center of Choi-wan dropped rain on parts of Luzon near Manila. Other bands in the southern half of Tropical Storm Choi-wan dropped rain on Mindoro. Choi-wan was still producing a few winds that were blowing at tropical storm force, but Manila did not report any winds that were that strong.

Tropical Storm Choi-wan exhibited an organized circulation on Wednesday afternoon. The inner end of a rainband wrapped around the western, southern and eastern sides of the center of Choi-wan. Other bands of thunderstorms were in the southern half of the tropical storm. Bands in the northern half of Tropical Storm Choi-wan consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 35 miles (55 km) from the center of Choi-wan.

Tropical Storm Choi-wan will move through an area that is marginally favorable for intensification during the next 24 hours. The center of Choi-wan will move over the South China Sea where the Sea Surface Temperatures are near 30°C. However, an upper level ridge centered over southern China will cause moderate vertical wind shear. The wind shear will limit the potential for intensification, but Tropical Storm Choi-wan could get a little stronger during the next 24 hours.

Tropical Storm Choi-wan will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Choi-wan toward the north during the next 24 hours. On its anticipated track the center of Tropical Storm Choi-wan will move northwest of Luzon during the next 24 hours. Choi-wan will turn toward the northeast on Friday after it moves around the western end of the high pressure system. Tropical Storm Choi-wan could approach the southern end of Taiwan in 36 hours.

Tropical Storm Choi-wan Brings Rain to Philippines

Tropical Storm Choi-wan brought rain to the central Philippines on Tuesday. At 11:00 p.m. EDT on Tuesday the center of Tropical Storm Choi-wan was located at latitude 13.1°N and longitude 121.9°E which put it about 155 miles (250 km) southeast of Manila, Philippines. Choi-wan was moving toward the west-northwest at 17 m.p.h. (28 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 1002 mb.

The center of Tropical Storm Choi-wan made an initial landfall on the east coast of Samar and then it moved west-northwest across the central Philippines. Choi-wan moved across the Sibuyan Sea and it was centered southeast of Manila on Tuesday night. The circulation around Tropical Storm Choi-wan weakened when the center passed over Samar, but it was still producing a small area of tropical storm force winds. Winds to tropical storm force extended out 35 miles (55 km) from the center of Choi-wan.

Tropical Storm Choi-wan dropped locally heavy rain over parts of Samar, Masbate, Panay and Mindoro on Tuesday. An upper level ridge centered over southern China was producing northeasterly winds which were blowing toward the top of Choi-wan. Those winds were producing moderate vertical wind shear and they causing the heavier rain to fall in bands in the southern half of Tropical Storm Choi-wan. Bands in the northern half of the tropical storm consisted primarily of showers and lower clouds.

Tropical Storm Choi-wan will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Choi-wan toward the north-northwest during the next several days. On its anticipated track the center of Tropical Storm Choi-wan could pass just south of Manila in 12 hours. Choi-wan could drop locally heavy rain on Mindoro and western Luzon. Heavy rain could cause flash floods in some locations.

Tropical Storm Choi-wan will move through an environment that is mostly unfavorable for intensification. Choi-wan will move over water where the Sea Surface Temperatures are near 30°C. However, the upper level ridge center over southern China will continue to cause moderate vertical wind shear. The wind shear will limit the potential for intensification. The eastern side of the circulation around Tropical Storm Choi-wan will be over Luzon during the next 24 hours, which will also be unfavorable for intensification.

Tropical Storm Blanca Weakens South of Baja California

Tropical Storm Blanca weakened south of Baja California on Tuesday afternoon. At 5:00 p.m. EDT on Tuesday the center of Tropical Storm Blanca was located at latitude 14.7°N and longitude 110.9°W which put it about 570 miles (915 km) south of the southern tip of Baja California. Blanca was moving toward the west-northwest at 8 m.p.h. (13 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.

After reaching its maximum intensity on Monday night when the sustained wind speed was 60 m.p.h. (95 km/h), Tropical Storm Blanca weakened on Tuesday afternoon. An upper level trough west of Baja California produced moderate southwesterly winds that blew toward the top of Blanca’s circulation. Those winds caused moderate vertical wind shear and the shear caused Tropical Storm Blanca to weaken. The vertical wind shear also caused an asymmetrical distribution of thunderstorms around Blanca. The strongest thunderstorms were occurring in bands on the eastern side of Tropical Storm Blanca. Bands in the western half of the tropical storm consisted primarily of showers and lower clouds. Winds to tropical storm force extended out 45 miles (75 km) from the center of Blanca.

Tropical Storm Blanca will move through an environment unfavorable for intensification during the next several days. Blanca will move over water where the Sea Surface Temperatures are near 28°C. However the upper level trough west of Baja California will cause strong vertical wind shear and the wind shear will cause Blanca to weaken. Tropical Storm Blanca could weaken to a tropical depression in a day or two.

Tropical Storm Blanca will move around the southern part of a subtropical high pressure system over the Eastern North Pacific Ocean. The high will steer Blanca toward the west-northwest during the next two days. On its anticipated track Tropical Storm Blanca will move farther away from Baja California.

Tropical Storm Choi-wan Nears the Philippines

Tropical Storm Choi-wan neared the central Philippines on Monday night. At 11:00 p.m. EDT on Monday the center of Tropical Storm Choi-wan was located at latitude 10.4°N and longitude 126.9°E which put it about 100 miles (160 km) east-southeast of Guiuan, Philippines. Choi-wan was moving toward the west-northwest at 11 m.p.h. (17 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 997 mb.

Tropical Storm Choi-wan was approaching Samar in the central Philippines on Monday night. An upper level ridge centered near Hong Kong was producing northeasterly winds that were blowing toward the top of Choi-wan. Those winds were causing moderate vertical wind shear and they were affecting the structure of the tropical storm. The stronger thunderstorms were occurring bands southwest of the center of Tropical Storm Choi-wan. The bands in the other parts of Choi-wan consisted mainly of showers and lower thunderstorms. Winds to tropical storm force extended out 65 miles (105 km) from the center of circulation.

Tropical Storm Choi-wan will move through an environment only marginally favorable for intensification during the next 12 hours. Choi-wan will move over water where the Sea Surface Temperatures are near 30°C. However, the upper level ridge will continue to cause moderate vertical wind shear. The wind shear will limit the potential for intensification. The center of Tropical Storm Choi-wan will move over land later on Tuesday.

Tropical Storm Choi-wan will move around the western end of a subtropical high pressure system over the Western North Pacific Ocean. The high pressure system will steer Choi-wan during the next 36 hours. On its anticipated track the center of Tropical Storm Choi-wan will reach Samar in 12 hours. Choi-wan will bring gusty winds and locally heavy rain to Samar. Heavy rain could cause flash floods in some locations. The center of Tropical Storm Choi-wan could reach the southeastern part of Luzon in 24 hours.