Bermuda Hurricane Season Guide

When Is Hurricane Season

The Atlantic hurricane season runs June 1 through November 30, with peak activity between mid-August and mid-October. Bermuda sits in the Atlantic recurvature zone — where hurricanes often turn northeast before reaching the US East Coast — making the island a frequent target for near-misses and glancing blows. Most years see at least one storm close enough to bring damaging winds or heavy rain. Once or twice a decade, a major hurricane makes a more direct hit.

My first was Hurricane Emily in 1987. It came unexpectedly — my dad had already left for work in Hamilton, and I was home with my mom and sister, sheltering in the bathroom while the storm tore through. I remember how loud it was, and watching Casuarina trees crash down outside. We lost electricity for about a week. Dad had to dip water from the tank with a bucket on a rope. That storm taught me early what every Bermudian eventually learns: hurricanes change how you live, eat, and get water for days or weeks. Being prepared at the start of June — not scrambling in September — is the only sensible approach.

What a Hurricane Does to Your Water Supply

Storm surge can contaminate cisterns in low-lying areas — saltwater intrusion requires professional cleaning and refilling. Heavy rain can overfill tanks, but overflow is routed out by design; don't count on a hurricane to solve a low tank. Wind damage to gutters knocks the collection system offline, and post-storm repairs come weeks later when tradespeople are in peak demand. Roof debris contaminates the first several rain events after a storm — inspect and clean the roof before treating the next rain as clean collection.

Pre-Hurricane Checklist

Top off your tank before a storm if possible — a miss can leave you dry for weeks if you relied on forecast rain that didn't arrive.

Clean gutters and downspouts before June. Blocked gutters mean rain runs off during the exact storms where collection matters most.

Check your tank lid seal — a loose lid allows contamination during flooding and surge.

Know your tank shutoff location. If surge is forecast, shutting the inlet protects against saltwater contamination. Know where the valve is before you need it in the dark.

Store a week's emergency drinking water separately — clean water insurance even if the tank is compromised.

After the Storm: Water Safety

Treat tank water with caution after any hurricane. The Bermuda Weather Service issues post-storm advisories that include water safety guidance. Visible debris, unusual colour or smell, or known flooding are all reasons to test before drinking. Boiling handles biological contaminants but won't remove salt or chemical contamination — if you suspect surge reached your inlet, stop drinking and get the water tested. For cooking and washing, tank water is generally fine while you assess.

How Tankrain BDA Tracks Storms

The Storm Tracker on the homepage pulls live NOAA data showing all active tropical systems and projected paths. The NDBC Buoy 41049 (South Bermuda) provides real-time wave height — often the first indicator of a distant system's approach, as swells arrive before the storm itself. During active periods, check both together for the clearest picture.

Understanding the Forecast: Wind vs. Surge vs. Rain

When a hurricane approaches, three separate hazards require different responses — and understanding which one poses the greatest risk to you specifically depends on your location on the island.

Wind is the most universally felt hazard. Cat 1 (65–82 kt) damages loose structures and vegetation. Cat 2 (83–95 kt) causes significant roof damage. Cat 3 and above (96+ kt) can cause structural damage to buildings. The north shore experiences stronger gusts from most hurricanes because storms approaching from the southwest push wind onto that exposure first. South shore residents get more direct swell.

Storm surge is dangerous for low-lying coastal areas — particularly around Harrington Sound, Hamilton Harbour, and the North Shore coastline. Surge rarely exceeds 1.5 metres in Bermuda's hurricanes, but that is enough to inundate ground-floor properties and contaminate any cisterns that aren't properly sealed above flood level.

Rainfall from a direct hurricane can be deceptive. Fast-moving storms (18+ kt forward speed) often produce less total rain than slow-moving ones, even at higher intensity. A Category 3 storm tracking northeast at 25 kt may deliver only 50–75mm, while a slow-moving Category 1 meandering nearby can drop 200mm over two days. For the purposes of tank refill, a slow-moving tropical storm is often more valuable than a fast-moving major hurricane — though infinitely more dangerous by other measures.

Rebuilding Your Tank After the Season

September and October often bring Bermuda's heaviest rainfall. After the season passes, use November–December rain and the tank calculator to assess your supply heading into winter. If you're below 50% going into December, consider an early delivery — the dry season starts in January, and getting ahead of it is far less stressful than scrambling in March.

More Guides