By PDC’s Senior Weather
Specialist Glenn James
The Pacific Disaster Center’s (PDC Global) Saturday, December 9, 2023, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas
Current Tropical Cyclones:
Tropical cyclone 03P (Jasper)…is located approximately 486 NM east of Cairns, Australia
Northeast Pacific Ocean:
The North Pacific hurricane season officially ended on November 30, 2023. Routine issuance of the Tropical Weather Outlook will resume on May 15, 2024. During the off-season, Special Tropical Weather Outlooks will be issued as conditions warrant.
The eastern Pacific basin hurricane season was above normal, with 17 named storms, of which 10 were hurricanes and eight of those major hurricanes.
From August 16 to 21, Tropical Storm Hilary brought widespread heavy rainfall and flooding to Southern California, with some areas receiving up to 600% of their normal August rainfall. Hilary resulted in the first ever issuance of Tropical Storm Watches and Warnings for the Southern California coastline by NOAA’s National Hurricane Center. In addition, the Center distributed key hazard focused messages for Hilary in Spanish through the agency’s new language translation project.
Hurricane Otis made landfall near Acapulco, Mexico, on October 25 as a category-5 hurricane, with sustained winds of 165 mph. Otis holds the record as the strongest landfalling hurricane in the eastern Pacific, after undergoing rapid intensification in which wind speeds increased by 115 mph in 24 hours.
Central North Pacific:
The central North Pacific hurricane season officially ended on November 30, 2023. Routine issuance of the Tropical Weather Outlook will resume on June 1, 2024. During the off-season, Special Tropical Weather Outlooks will be issued as conditions warrant.
The central Pacific basin had a near-normal season with four tropical systems traversing the basin.
Hurricane Dora, a category-4 storm, passed south of Hawaii in early August, marking the first major hurricane in the central Pacific basin since 2020. The strong gradient between a high pressure system to the north and Dora to the south was a contributing factor to the wind-driven, fast-moving wildfires in Hawaii.
Western Pacific, Indian Ocean and adjacent Seas:
Southwest Pacific Ocean…
Tropical cyclone 03P (Jasper)
According to the JTWC warning number 21, sustained winds were 55 knots…with gusts to 70 knots
Animated enhanced infrared satellite imagery depicts tropical cyclone 03P (Jasper) continuing to fight against prominent vertical wind shear (vws) and mid-level dry air entrainment over the past six hours. The systems mid to upper-level vortex has managed to wobble back equatorward into better vertical alignment with the low level circulation center (llcc), despite the
persisting moderate to high (20 to 25 knot) vws.
A scatterometry image captured an asymmetric wind field expanding much further to the south than north, although the symmetry has improved since the previous warning. Deep convection, though still present up to 116 NM outward from the llcc in the western periphery, has weakened and rising cloud top temperatures are observed on IR satellite imagery.
TC 03P continues experiencing vertical wind shear and numerical model indicated moderate mid-level dry air entrainment. Both are expected to continue influencing the system over the next 24 hours, transpiring a weakening trend to occur as the system tracks west-southwestward.
After 24 hours and on a westward track, vws is expected to rapidly decrease to low (5-10 knot) values, allowing the TC a sustainment window with dry mid-levels still a factor. Warm sea surface temperatures in the shallow reefs along the forecast track will assist the TC by supplying necessary heat to the system.
Near 48 hours, the system is forecast to track west-northwestward until 72 hours. Multiple indicators in intensity guidance show TC 03P to likely undergo a re-moistening of the core and slight re-intensification between 60 hours and landfall (near 84 hours), potentially peaking at 60-65 knots.
A rapid decay is anticipated from 84 to 120 hours, as the system tracks westward across northeastern Australia. Of note, multiple global models transit the vortex across the Cape York Peninsula through 120 hours, and into the Gulf of Carpentaria outside of the forecast window, where re-intensification to TC strength is possible.