Current Snapshot

The Pacific Disaster Center’s (PDC Global) Saturday, September 28, 2024, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas

Current Tropical Cyclones:

Tropical Cyclone 19W (Jebi), is located about 774 NM south of Yokosuka, Japan

Tropical Cyclone 20W (Krathon), is located about 311 NM northeast of Manila, Philippines

Northeast Pacific Ocean: There are no Tropical Cyclones 

>>> Offshore of Southern and Southwestern Mexico:

An area of low pressure could form off the coast of southern or
southwestern Mexico in a few days. Thereafter, some slow
development is possible while the system drifts westward or
northwestward.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 7 days…low…30 percent

Central Pacific Ocean: There are no Tropical Cyclones.

Western Pacific, Indian Ocean, and adjacent Seas:

Tropical Cyclone 19W (Jebi)

According to the JTWC warning number 11, sustained winds were 30 knots, with gusts to 40 knots.

As indicated in animated multi-spectral satellite imagery (msi), tropical depression 19W continues to struggle, with deep convection flaring over the eastern semicircle of a partially-exposed low-level circulation.

Upper-level conditions remain marginally favorable due to the presence of an upper-low over and to the west of the system, which is producing upper-level convergence and subsidence over the western semicircle thus inhibiting convective development. Upper-level diffluence is confined to the eastward and equatorward regions of the system, aiding in sustainment of deep convection over those regions.

TD 19W is forecast to track poleward along the southwestern and western periphery of the ridge through 48 hours, with steady development as the upper-low gradually weakens. After 48 hours, the system will round the ridge and intensify to typhoon strength, due to improving poleward outflow associated with a deepening major shortwave trough expected to dig over western Japan.

The system will eventually track into the mid-latitude westerlies north of the ridge and commence extra-tropical transition (ett). TD 19W will complete ett by 96 hours as it accelerates poleward and gains frontal characteristics.

Tropical Cyclone 20W (Krathon)

According to the JTWC warning number 8, sustained winds were 60 knots, with gusts to 75 knots.

Animated visible satellite imagery showed a fully exposed low level circulation center (llcc), but the llcc has since become tucked under a plume of deep convection. Extensive cyclonic turning is evident throughout the low level cloud lines, demonstrating the broad extent of the system. Multiple convective bands are pulsing in the southern semicircle, sheared to the southwest with diffuse outflow.

The system has been drifting slowly southward in a col region but is expected to become more heavily influenced by the subtropical ridge to the northeast, which will turn its track westward and slowly curve it northward over the next few days with speeds remaining climatologically slow. The track is expected to come into close proximity with the east coast of Taiwan, but the distance remains uncertain at this time.

Due to the slow movement of the system, the system is expected to have ample opportunity to strengthen between 24 and 72 hours while it treads over warm waters and experiences favorable environmental conditions. After 72 hours, TS 20W will have moved far enough north to begin interacting with the westerlies aloft, which will open up a poleward outflow channel in addition to the continued healthy equatorward outflow.

However, development will become hampered by the land interaction as the track ventures close to Taiwan and eventually the vertical wind shear will strengthen to unfavorable amounts.