Current Snapshot

The Pacific Disaster Center’s (PDC Global) Thursday, September 4, 2025, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas

Current Tropical Cyclones:

Tropical Cyclone 11E (Kiko) is located about 1360 miles east-southeast of Hilo, Hawaii

Tropical Cyclone 12E (Lorena) is located about 175 miles west of Cabo San Lazaro, Mexico

Tropical Cyclone 21W (Peipah) is located about 171 miles east of Iwakuni, Japan

Northeast Pacific Ocean: 

Tropical Cyclone 11E (Kiko)

KIKO WEAKENS SLIGHTLY WELL TO THE EAST-SOUTHEAST OF HAWAII

According to the NHC advisory number 20

Kiko is moving toward the west near 9 mph (15 km/h). A gradual turn toward the west-northwest is expected tonight and Friday, with this motion forecast to continue through the weekend with a slight increase in forward speed. Maximum sustained winds are near 125 mph (205 km/h) with higher gusts. Kiko is a category 3 hurricane on the Saffir-Simpson Hurricane Wind Scale. Some strengthening is possible tonight and Friday, followed by slow weakening Friday night through the weekend. Hurricane-force winds extend outward up to 25 miles (35 km) from the center and tropical-storm-force winds extend outward up to 80 miles (130 km).

Tropical Cyclone 12E (Lorena) 

LORENA EXPECTED TO BECOME POST-TROPICAL VERY SOON… …MOST IMPORTANTLY, THE RISK OF LIFE-THREATENING FLASH FLOODING CONTINUES FOR BAJA CALIFORNIA SUR AND SONORA THROUGH FRIDAY

According to the NHC advisory number 13

Lorena is moving toward the northwest near 5 mph (7 km/h). A slow north-northwestward to northwestward motion is expected through early Saturday, followed by a turn toward the west-northwest over the weekend. Maximum sustained winds have decreased to near 45 mph (75 km/h) with higher gusts. Additional weakening is forecast, and Lorena is expected to become a remnant low by Friday morning. The remnant low is likely to dissipate by late Sunday. Tropical-storm-force winds extend outward up to 60 miles (95 km) to the northwest of the center.

HAZARDS AFFECTING LAND

RAINFALL: Bands of heavy rainfall will continue to impact Baja California Sur and Sonora Mexico through Friday. Additional rainfall totals of 4 to 8 inches, with maximum storm total amounts of 15 inches, are possible across portions of Baja California Sur, far southeast Baja California and southwestern Sonora into Friday. This will bring the risk of life-threatening flash floods and mudslides, especially in areas of higher terrain.

Elsewhere across Mexico, 2 to 4 inches of rain, with isolated totals up to 6 inches, are expected across the remainder of Sonora and northern Sinaloa. These amounts will lead to isolated to scattered instances of flash flooding.

Across the southwestern United States, 1 to 3 inches of rain, with isolated totals up to 5 inches, are expected across portions of Arizona and New Mexico through Saturday, bringing the potential for isolated to scattered flash flooding.

WIND: Tropical storm conditions, mainly in gusts, are expected somewhere within the warning area in Baja California Sur today through Friday.

SURF: Swells generated by Lorena will continue affecting portions of the south and west coasts of Baja California Sur through Friday. These swells are likely to cause life-threatening surf and rip current conditions.

Central Pacific Ocean: There are no active tropical cyclones

The National Hurricane Center is issuing advisories on Hurricane Kiko, located in the East Pacific basin well east-southeast of the Hawaiian Islands. Kiko is expected to cross into the central Pacific basin Friday night.

The National Hurricane Center is also issuing advisories on Hurricane Lorena, located in the East Pacific basin just off the west coast of Baja California Sur.

Tropical cyclone formation is not expected during the next 7 days.

Animated enhanced infrared (eir) satellite imagery depicts a completed obscured low level circulation center (llcc) with persistent convection over the center. Additionally, a defined convective band is wrapping around the eastern semicircle with a dry slot to its immediate west. A 041126z metop-b ascat image reveals an asymmetric wind field with 25-30 kt winds confined to the southeastern quadrant.

The environment is assessed to be marginal, characterized by low to moderate (15-20 knots) vertical wind shear (vws), very warm (30-31 c) sea surface temperatures (sst), and strong poleward outflow aloft, offset by terrain interaction with southern Japan and dry air entrainment.

Tropical storm 21W is forecast to continue its northeastward track along the northwestern periphery of the subtropical ridge. 21W will track along the southern coast of Japan, skirting the coast until it emerges over water at 24 hours. After 24 hours, a deep upper-level trough is expected to quickly absorb 21W, completing extratropical transition (ett) no later than 36 hours.

Up until ett, 21W will marginally intensify due to robust poleward outflow and very warm ssts, hindered by land interaction and dry air entrainment. The strongest winds are forecast to remain off the coast of Japan until after 21W tracks completely offshore after 24 hours. As the system undergoes ett, the wind field will expand and intensify to 45 knots due to baroclinic forcing.

Some deterministic models indicate the possibility of 21W detaching from the frontal boundary after 36 hours and remaining quasi-stationary near the 155E longitude before dissipating. As a result, there is some uncertainty at the end of the JTWC track
forecast.

>>> There’s an area of disturbed weather being referred to as Invest 97W, which is located approximately 58 NM west-southwest of Vigan.

Animated multispectral satellite imagery (msi) depicts a weakly defined circulation center that is obscured by flaring convection in the northern periphery of 97W.

Environmental analysis for the area indicates a favorable condition for development with 15-20 knots of vertical wind shear, warm sea surface temperatures (29-30 c), and moderate equatorward
outflow aloft.

Global deterministic models are in good agreement that 97W will develop and track northward southwest of Tiwan, with GFS indicating faster development. Ensembles are in good agreement that 97W will track northward with ECENS being the more aggressive and favors the development southwest of Taiwan.

Maximum sustained surface winds are estimated at 13 to 18 knots.

The potential for the development of a significant tropical cyclone within the next 24 hours is low.