Hurricane Michael in the Area of Mexico Beach, Florida

Andrew Kennedy,James Kaihatu,Margaret Owensby,Anderson Gradel,Spencer Rogers,Douglas Krafft,Jean-Paul Pinelli,Andrew Copp,Matt Janssen,Zachariah Silver,David O Prevatt,Patrick Lynett,David Roueche,Kurtis Gurley,Matthew Florence

doi:10.1061/(asce)ww.1943-5460.0000590

Abstract

Category 5 Hurricane Michael made landfall near Mexico Beach, Florida on October 9, 2018, with measured high water marks (HWMs) reaching 7.2 m NAVD88. The town itself received great damage, with many areas destroyed down to the foundations. In this study, we document the storm and its effects on the greater Mexico Beach area: hazard, structural damage, and their relationships. Wave and surge damage was nearly total for low-lying properties, but damage decreased greatly with increasing elevation. Major wave and surge damage was noted in Federal Emergency Management Agency (FEMA) X zones, which are out of the 100-year floodplain, and it is suggested that the 100-year storm is a deficient measure for categorizing flood risk.

Highlights

Hurricane Michael made landfall 13 km (7 nautical miles) west of Mexico Beach, Florida, USA at 18:00 UTC (13:00 local) on October 9, 2018, as a Category 5 storm with maximum 1 min sustained winds of 140 knots (72 m/s), and a minimum central pressure of 91.9 kPa (Beven et al 2019)
Mexico Beach was an unfortunate testbed for the effects of waves and surge on a variety of construction types
Inundation elevations from wave runup were greatest on the side of a small hill by the beach, and surge inundation appeared to be largest in the northwestern Mexico Beach

Summary

Introduction

Hurricane Michael made landfall 13 km (7 nautical miles) west of Mexico Beach, Florida, USA at 18:00 UTC (13:00 local) on October 9, 2018, as a Category 5 storm with maximum 1 min sustained winds of 140 knots (72 m/s), and a minimum central pressure of 91.9 kPa (Beven et al 2019). Heights reached a maximum of just over Hs ≈ 2 m very near to the time of peak surge when mean water depths were probably > 3 m above ground elevation (we do not know the ground elevation during the storm so it is not possible to say with certainty), these were highly nonlinear waves capable of causing great damage to structures and infrastructure.

Results

Conclusion