Current Snapshot

The Pacific Disaster Center’s (PDC Global) Sunday, September 29, 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 608 NM south of Yokosuka, Japan

Tropical Cyclone 20W (Krathon), is located about 309 NM south of Taipei, Taiwan

Northeast Pacific Ocean: There are no Tropical Cyclones 

>>> Offshore of Southern and Southwestern Mexico:

An area of low pressure is forecast to develop off the coast of southern or southwestern Mexico in a day or two. Thereafter, environmental conditions appear generally favorable for additional development, and a tropical depression could form by the middle to latter part of this week while the system drifts slowly westward or northwestward.

* Formation chance through 48 hours…low…near 0 percent
* Formation chance through 7 days..medium…50 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 14, sustained winds were 40 knots, with gusts to 50 knots.

Animated water vapor imagery and upper-level winds reveal a slowly improving environment, with the broad upper-level low and large subsident region shifting to a slightly more favorable configuration to the west, allowing for improved poleward venting. As indicated in animated multi-spectral satellite imagery, deep convection has begun to build over the broad center. However, due to the broad nature of the center, there are multiple mesovorticies rotating cyclonically around a defined centroid.

Tropical storm 19W is forecast to track northward along the western periphery of the ridge through 36 hours. Steady intensification is anticipated as the upper-low to the west, currently inhibiting significant intensification, fills allowing for improved poleward venting. After 36 hours, the system will begin to round the ridge and commence extra-tropical transition (ett) as itinteracts with a shortwave trough south of mainland japan.

The peak intensity of 60 knots will occur near 48 hours due to robust poleward outflow into the aforementioned upper-level trough. The system will complete ett by 72 hours, as it accelerates into the mid-latitude westerlies east of Hokkaido and rapidly gains frontal characteristics. After  60 hours, the system will weaken quickly due to increasing vertical wind shear and cooler sea surface temperature values.

Tropical Cyclone 20W (Krathon)

According to the JTWC warning number 11, sustained winds were 105 knots, with gusts to 130 knots.

Animated multi-spectral satellite imagery depicts typhoon 20W (krathon) opened up a broad, raggedly-defined eye several hours ago which has since become cloud-filled. The outflow could be described as moderate radial but is most pronounced in the equatorward direction due to its broad extent reaching the vigorous northeasterly flow over the Philippines. The system is hinting at opening up a poleward outflow channel into the mid-latitude westerlies, but it has not yet connected with this mechanism. Deep
convection is evident, particularly on the northeast side within an inner and outer band, but the overall symmetry suggests the system is quickly becoming better organized.

The system is expected to continue strengthening at rapid intensification (ri) levels throughout the duration of its expected track slowly northwestward, passing through the Luzon Strait over excessively warm sea surface temperatures and favorable vertical wind shear values of 5-10 knots. The high ocean heat content values across the Luzon Strait alleviate concern of a depletion of warm water fueling the intensification.

The period of strengthening will level off by 48 hours due to increasing land interaction with Taiwan. The expected track will curve sharply to the northeast and take the core of the system across the southern (Hengchun) Peninsula of Taiwan.

A quick decay in Krathon’s strength will occur near 72 hours and after. The wind field, which is already extensive for this system, will gradually expand with the onset of intensity decline. Typhoon Krathon will begin to accelerate northeastward through the East China Sea as the subtropical ridge to the east latches on as the dominant steering influence driver.