Current Snapshot

The Pacific Disaster Center’s (PDC Global) Thursday, March 21, 2024, Tropical Cyclone Activity Report…for the Pacific Ocean, the Indian Ocean, and adjacent Seas

Current Tropical Cyclones:

Tropical Cyclone 18S (Neville)…is located approximately 702 NM west-northwest of Learmonth, 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 land falling 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

South Indian Ocean…

Tropical Cyclone 18S (Neville)

According to the JTWC warning number 37, sustained winds were 115 knots…with gusts to near 140 knots.

Tropical cyclone 18S (Neville) has rapidly intensified over the past 12 hours, vastly overshooting global numerical model and mesoscale model guidance.

Animated enhanced infrared satellite imagery depicts tropical cyclone 18S with an improved, clear and symmetric pinhole eye along with a very tight, compact ring surrounding the eyewall. There appears to be some slight pressure induced by northerly vertical wind shear on the northern semicircle of the system, but does not seem to be impacting the
cocooned inner structure. The eye is assessed with a diameter of 11 NM. 

TC 18S will track westward to west-southwestward along the northern periphery of the southern ridge through 72 hours while rapidly intensifying to a peak intensity of 90 knots by 36 hours. The system should maintain 90 knots through 48 hours with steady weakening after 60 hours due to increasing (15-25 knot) northwesterly vertical wind shear and dry air entrainment.

The current environment is assessed as highly favorable with strong poleward outflow aloft, low (5-10 knot) vertical wind shear, and warm sea surface temperatures.

TC 18S is forecast to continue tracking westward along the northern periphery of the southern ridge (str) through 24 hours. After 24 hours, the system is forecast to track west-southwestward as it begins to round the northwestern periphery of the str through 72 hours. After 72 hours, the system is anticipated to initiate a poleward turn as it completes the track around the southwestern quadrant of the str.

TC 18S is forecast to continue to intensify to 120 knots near 12 hours and maintain through 24 hours due to an increase in outflow aloft and a continuation of low vertical wind shear values (vws). Near 36 hours, vws values begin to increase to over 20 knots, and the system is forecast to weaken to 105 knots. As vws continues to increase and dry air starts to entrain into the system, TC 18S is forecast to further weaken to 85 knots near 48 hours and to 55 knots near 72 hours.

By 96 hours, the system is forecast to dissipate to 30 knots as vws increases to over 30 knots and dry air entrains the system, resulting in a decoupling of the mid and upper level support from the low level circulation.