Hurricane Storm Surge Estimator

Estimate storm surge height from hurricane category and coastal geometry.
Understand surge risk by Saffir-Simpson category for coastal planning.

Estimated Storm Surge

Storm surge is an abnormal rise of water generated by a hurricane’s winds pushing ocean water toward shore. It is the deadliest hurricane hazard — responsible for approximately half of all hurricane-related deaths.

Storm surge vs. storm tide:

  • Storm surge: the surge above normal astronomical tide (the dangerous component)
  • Storm tide: storm surge + normal high tide (total water level at shore)

Saffir-Simpson Scale and typical surge heights:

  • Tropical Storm: 1–2 ft (0.3–0.6 m) surge
  • Category 1 (74–95 mph): 4–5 ft (1.2–1.5 m)
  • Category 2 (96–110 mph): 6–8 ft (1.8–2.4 m)
  • Category 3 (111–130 mph): 9–12 ft (2.7–3.7 m)
  • Category 4 (131–155 mph): 13–18 ft (4.0–5.5 m)
  • Category 5 (>155 mph): 18+ ft (5.5+ m)

These are general ranges. Actual surge depends heavily on:

  • Coastal geometry: Shallow bays and estuaries funnel and amplify surge
  • Angle of approach: Onshore track vs. glancing blow
  • Storm size: A large, slow storm pushes more water than a small, fast one
  • Bathymetry: Shallow offshore areas amplify surge significantly

Historic examples: Hurricane Katrina (2005) produced 28 ft surge near Pass Christian, MS. Hurricane Harvey (2017) caused 10–12 ft surge. Hurricane Michael (2018, Cat 5) caused 14 ft surge in Mexico Beach, FL.

Evacuation zones: US coastal counties use letter zones (A, B, C…) corresponding to surge risk. Zone A evacuates for Cat 1 threats. Follow official evacuation orders — no property is worth a life in a surge event.


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