Current Snapshot

The Pacific Disaster Center’s (PDC Global) Sunday, July 21, 2024, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas

Current Tropical Cyclones:

Tropical Cyclone 04W (Prapiroon)…is located approximately 204 NM east-southeast of Hanoi, Vietnam

Tropical Cyclone 05W (Gaemi)…is located approximately 513 NM south-southeast of Taipei, Taiwan

Northeast Pacific Ocean:

>>> Western East Pacific:

A large area of disorganized showers and thunderstorms located over the far western portion of the eastern Pacific is associated with a trough of low pressure.

Environmental conditions are forecast to be marginally conducive for some slow development during the next day or so.

The disturbance is forecast to move westward at 10 to 15 mph and into the central Pacific basin tonight, and by mid-week, strong upper-level winds are expected to inhibit further development.

* Formation chance through 48 hours…low…10 percent
* Formation chance through 7 days…low…10 percent

>>> Central and Western East Pacific:

A tropical wave located about 900 miles south-southwest of the southern tip of the Baja California Peninsula is producing disorganized shower and thunderstorm activity.

Environmental conditions could become a little more conducive for some gradual development of this system over the next several days while it moves westward to west-northwestward at 10 to 15 mph across the central
and western portions of the basin.

* Formation chance through 48 hours…low…10 percent
* Formation chance through 7 days…low…30 percent

Central North Pacific:

Approximately 1,100 miles east-southeast of Hilo, Hawaii:

A large area of disorganized showers and thunderstorms located over the far western portion of the eastern Pacific is associated with a trough of low pressure.

Environmental conditions are forecast to be marginally conducive for some slow development during the next day or so. The disturbance is forecast to move westward at 10 to 15 mph and into the central Pacific basin tonight. By midweek, strong upper-level winds are expected to inhibit further development.

* Formation chance through 48 hours…low…10 percent
* Formation chance through 7 days…low…10 percent

Western Pacific, Indian Ocean and adjacent Seas

>>> Western Pacific…

Tropical Cyclone 04W (Prapiroon)

According to the JTWC advisory number 10, sustained winds were 45 knots…with gusts to 55 knots.

Animated enhanced infrared satellite imagery depicts tropical storm 04W (Prapiroon) tracking quickly north-northwestward over the past 6 hours. the convection has started to build over the center and the system has become compact in size as it tracks toward hainan.

Environmental analysis indicates that 04W is in a marginally favorable environment for further intensification characterized by good equatorward outflow aloft, low (10-15 knot) vertical wind shear, and warm sea surface temperatures. As the system nears Hainan the environment will quickly worsen due to land interaction.

TS o4W is forecast to continue on a northwestward track, along the western periphery of the ridge throughout the remainder of the forecast period.

The peak intensity remains at 40 knots due to its proximity to Hainan. After 12 hours, 04W will begin a weakening trend and drop to around 25 knots due to very high vertical wind shear values (30 knots) in the Gulf of Tonkin. Ridging to the north is anticipated to start driving the system westward after making landfall near 48 hours. After making landfall though, 04W will quickly dissipate.

Tropical Cyclone 05W (Gaemi)

According to the JTWC advisory number 10, sustained winds were 50 knots…with gusts to 65 knots.

Animated enhanced infrared satellite imagery depicts tropical storm 05W (Gaemi) with a degraded convective appearance over the past 6 hours. The partially exposed low-level circulation center (llcc) is offset to the northeast of the deep convection and well-defined. Banding features can be seen along the western and southern peripheries. Prominent northeasterly shear is evident with convection blowing off to the west-southwest and has prevented the system from intensifying. 05W has been quasi-stationary over the past 12 hours in response to the competing steering environment in place.

Environmental analysis indicates that 05W is in a marginally favorable environment for further intensification characterized by moderate poleward and equatorward outflow aloft, 15 to 20 knots of vertical wind shear, and warm sea surface temperatures.

TS 05W is forecast to begin a northward turn over the next 12 hours as the ridge to the north reorients to a north-south orientation, which will drive 05w north-northwestward through 72 hours. After 72 hours, ridging extending over eastern china will develop and steer the system more northwestward through the remainder of the forecast period.

05W is currently forecast to make landfall along the eastern coast of China just after 96 hours. The RI indicators that were present during the previous forecast have since been lost, lending more confidence in the short-term intensity forecast. the vertical wind shear currently present may be the limiting factor.

05W is forecast to steadily intensify over the next 72 hours to a slightly reduced peak of 90 knots near Ishikagijima. Very warm sea surface temperatures (sst) will be the main driving factors for the development of the system. After 72 hours, 05W is expected to begin its weakening trend as it enters cooler ssts and vertical wind shear begins to rise. 05W is expected to be typhoon strength at landfall, but rapidly deteriorates over eastern China.