Tropical Cyclone Yasa made landfall on Fiji’s Vanua Levu Island (population 136,000) at 6Z (1 a.m. EST) Thursday, December 17, as a high-end category 4 storm with 145 mph winds, according to the Joint Typhoon Warning Center (JTWC). Yasa is the second-strongest cyclone on record to make landfall in Fiji, behind Tropical Cyclone Winston, which hit Fiji’s Koro Island as a category 5 storm with 180 mph winds in 2016.
Yasa peaked as a low-end category 5 storm with 160 mph winds with a central pressure of 914 mb at 0Z Wednesday, and maintained category 5 strength through 12Z Wednesday. In the hours leading up to landfall, the cyclone underwent an eyewall replacement cycle (ERC), a process common in intense cyclones, in which the eyewall shrinks, grows unstable, and collapses, with a new eyewall forming out of an outer spiral band. This process weakened Yasa’s peak winds by 15 mph, but increased the storm surge, as the region of ocean experiencing hurricane-force winds expanded. Yasa’s impact on Fiji’s Vanua Levu Island is likely to be devastating.
Forecast for Yasa
At 10 a.m. EST December 17, Yasa was a low-end category 4 storm with 130 mph winds, headed southeast at 16 mph. High wind shear of 20-25 knots and declining sea surface temperatures along the cyclone’s track will result in steady weakening. Yasa’s track will take it near some of the smaller Fijian islands, but no major populated areas are likely to experience a direct impact from the cyclone.
Yasa is the southeast Pacific’s second category 5 storm of 2020
Yasa is the second category 5 storm observed in the Southeast Pacific in 2020, joining Tropical Cyclone Harold, which devastated Vanuatu and Fiji in April. In only one other year (1998) have two category 5 cyclones been observed in the Southeast Pacific. Since reliable satellite data for the Southeast Pacific became available in the 1980s, there have been 15 category 5 storms in the basin, as classified by the JTWC. Yasa is the earliest category 5 on record in the Southeast Pacific, where the cyclone season straddles calendar years. The next earliest, Cyclone Zoe, peaked as a Cat 5 on December 27, 2002.
Bob Henson contributed to this post.
Posted on December 17, 2020(12:46pm EST).