Current Snapshot

The Pacific Disaster Center’s (PDC Global) Saturday, August 12, 2023, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas

Current Tropical Cyclones:

Tropical Cyclone 05E (Dora)…is located about 810 miles west of Johnston Island

Tropical Cyclone 07E…is located about 595 miles south-southwest of the southern tip of Baja California

Tropical Cyclone 07W (Lan)…is located approximately 360 NM south of Yokosuka, Japan

Northeast Pacific Ocean:

Tropical Cyclone 07E…is located about 595 miles south-southwest of the southern tip of Baja California

NEW TROPICAL DEPRESSION FORMS OVER THE OPEN EAST PACIFIC

According to the NHC advisory number 1…

The depression is moving toward the west-northwest near 10 mph and this general motion is expected to continue for the next few days.

Maximum sustained winds are near 35 mph with higher gusts. Steady strengthening is expected, and the depression is forecast to become a tropical storm tonight and a hurricane in a couple of days.

Western East Pacific…

Invest 99E

A broad area of low pressure associated with a tropical wave is producing a large area of disorganized showers and thunderstorms well to the east-southeast of the Hawaiian Islands. Conditions appear conducive for development of this system, and a tropical depression is likely to form during the next few days while moving toward the west or west-northwest at about 10 mph across the far western portion of the basin, crossing into the Central Pacific basin late Sunday.

* Formation chance through 48 hours…medium…60 percent
* Formation chance through 7 days…high…80 percent

Off the coast of southern Mexico…

An area of low pressure is forecast to form offshore of Central America and the southern coast of Mexico in a couple of days from a tropical wave currently moving across the southern portion of Central America. Environmental conditions are expected to be conducive for development of this system, and a tropical depression is likely to form during the early or middle part of next week while it moves generally west-northwestward, roughly parallel to the coast of southern and southwestern Mexico.

* Formation chance through 48 hours…low…10 percent
* Formation chance through 7 days…high…80 percent

Central Pacific Ocean:

>>> Far east-southeast of the main Hawaiian Islands:

Invest 99E

A broad area of low pressure associated with a tropical wave is producing a large area of disorganized showers and thunderstorms well to the east-southeast of the Hawaiian Islands. Conditions appear conducive for development of this system, and a tropical depression is likely to form during the next few days while moving toward the west or west-northwest at about 10 mph across the far
western portion of the basin, crossing into the Central Pacific basin late Sunday.

* Formation chance through 48 hours…medium…60 percent
* Formation chance through 7 days…high…80 percent

Western Pacific, Indian Ocean and adjacent Seas:

Western Pacific…

Tropical Cyclone 05E (Dora)

According to the JTWC warning number 50…

Sustained winds are 65 knots…with gusts to 80 knots

Animated enhanced infrared satellite imagery shows a significantly deteriorating system with its northern flank getting frayed and sheared poleward.

Analysis indicates an unfavorable environment with warm sea surface temperatures and strong poleward outflow offset by moderate-strong vertical wind shear.

Typhoon Dora will continue on a northwestward track passing Wake Island approximately 215 NM to the southwest. After 48 hours, it will turn more northward as it rounds the ridge axis. The unfavorable environment will become worse with increasing vertical wind shear and gradually erode the system down to 55 knots by 48 hours.

After 48 hours, increasing poleward outflow ahead of a mid-latitude trough will temper the weakening down to 50 knots by 120 hours, when it begins extra-tropical transition.

Tropical Cyclone 07W (Lan)

According to the JTWC Warning number 21…

Sustained winds were 65 knots…with gusts to near 80 knots

Animated enhanced infrared satellite imagery shows a medium-sized symmetrical cyclone that has mostly maintained its overall convective and wrap structure, albeit with an enlarged 60 NM banding eye, exposing a defined low level circulation center.

Analysis indicates a marginally favorable environment with low vertical wind shear and moderate outflow offset by localized low sea surface temperatures due to oceanic upwelling and dry air intrusion.

Typhoon Lan will continue on its current track toward central Honshu, Japan. After 48 hours, it will track more northward as the ridge recedes in response to a mid-latitude trough approaching from the northwest, make landfall near Minamise around 60 hours, crest the ridge axis by 72 hours, exit into the Sea of Japan, then accelerate northeastward on the poleward side of the ridge.

The marginal environment will sustain the current intensity of 80 knots up to 24 hours. Afterward, increasing vertical wind shear, dry air intrusion, then land interaction will reduce it to 50 knots by 72 hours. Despite the relatively warm sea surface temperatures in the Sea of Japan, increasing vertical wind shear, then interaction with the baroclinic zone as TY 07W begins extra-tropical transition around 96 hours will gradually erode it to a 40 knot cold core low by 120 hours.