Hurricane Fernanda Rapidly Weakens, Expected to Become Post-Tropical Cyclone Soon
Hurricane Fernanda is rapidly weakening as it encounters less favorable environmental conditions. Its structure has become less organized, showing signs of raggedness, and convection has dissipated, particularly on its northern side. Infrared satellite observations have revealed a deterioration in its cloud tops, indicating a weakening trend.
The subjective Dvorak final-T estimates, which measure a storm’s intensity, were lower for this cycle compared to previous assessments. However, some objective intensity estimates from UW-CIMSS still suggest slightly higher values. Taking into account a blend of satellite estimates, as well as assuming a delay in the reduction of Fernanda’s winds, the initial intensity of the storm for this advisory is set at 65 kt.
The factors contributing to Fernanda’s continued weakening are vertical wind shear, rapidly cooling sea-surface temperatures, and mid-level relative humidity below 40 percent. This combination will lead to further rapid weakening, causing Fernanda to transition into a tropical storm very soon and eventually become a post-tropical cyclone within the next 36 hours.
Global model simulated infrared satellite images provide agreement that Fernanda will lose its deep convection, indicating a lack of significant thunderstorm activity, within the next 36 hours. The remnants of the storm are likely to dissipate into a trough by day 5.
Fernanda’s movement remains primarily westward, guided by a mid-level ridge. The track guidance for this cycle has shifted slightly south, possibly due to the storm’s rapid weakening and influence from the low-level flow. Consequently, the latest track forecast from the National Hurricane Center predicts a slight southward shift compared to the previous one, although it does not align completely with the HCCA corrected consensus.
Forecast positions and maximum wind speeds for Fernanda are predicted as follows:
– Initial (16/0900Z): 17.4N 125.5W, 65 kt, 75 mph
– 12 hours (16/1800Z): 17.2N 127.5W, 55 kt, 65 mph
– 24 hours (17/0600Z): 17.1N 130.2W, 40 kt, 45 mph
– 36 hours (17/1800Z): 17.2N 132.9W, 35 kt, 40 mph (post-tropical)
– 48 hours (18/0600Z): 17.3N 135.7W, 30 kt, 35 mph (post-tropical/ remnant low)
– 60 hours (18/1800Z): 17.5N 138.7W, 25 kt, 30 mph (post-tropical/ remnant low)
– 72 hours (19/0600Z): 17.7N 141.6W, 20 kt, 25 mph (post-tropical/ remnant low)
– 96 hours (20/0600Z): 17.7N 147.6W, 20 kt, 25 mph (post-tropical/ remnant low)
– 120 hours (21/0600Z): Dissipated
The weakening of Hurricane Fernanda and its anticipated transition into a post-tropical cyclone underscores the importance of ongoing monitoring and preparedness efforts. While its impact is expected to diminish, it is crucial for residents in affected areas to remain vigilant and follow the guidance of local authorities to stay safe during the storm’s passage.
