Why Your Power Keeps Tripping After Heavy Rain (Brisbane Storm Season Electrical Causes)
A Brisbane-focused storm-season guide explaining why your power keeps tripping after heavy rain, the most common moisture-related electrical causes, and the warning signs homeowners should never ignore.
If your power keeps tripping after heavy rain, it’s not “just the weather.”
In Brisbane, this is one of the most common storm-season electrical problems; especially in homes with older outdoor wiring, weather-exposed power points, or moisture-prone switchboards.
And here’s the truth:
When power trips during or after rain, it’s usually because water is getting into somewhere it shouldn’t.
That can mean:
earth leakage faults
damaged insulation
unsafe outdoor wiring
hidden moisture inside a power point or junction box
real risk of electric shock or electrical fire
This is exactly what the safety switch (RCD) is designed to prevent.
Let’s break down the most common causes, what to check, and when to call a licensed electrician.
Quick Diagnosis Checklist (Before You Reset It)
If your power trips after rain, check these first:
Did the trip happen after using outdoor power?
Was an outdoor extension lead left plugged in?
Was the rain heavy or windy (driving water into fittings)?
Does the safety switch trip instantly or after a few minutes?
Does it happen every time it rains, or only sometimes?
If it’s repeating, don't keep resetting. The fault will get worse.
1. Outdoor Power Points Taking On Water (Most Common Cause)
Brisbane backyards are full of outdoor GPOs that look fine but aren’t properly sealed anymore.
After years of UV and weather exposure, seals fail and water gets inside.
Common triggers:
driving rain hitting the wall face
cracked covers
loose faceplates
insects and dirt allowing water to pool
old outdoor fittings not rated properly
Signs:
the safety switch trips shortly after rain
it trips when you use outdoor power
it trips when outdoor lights turn on
you notice moisture inside the cover
2. Water in Outdoor Lighting or Garden Wiring
Landscape lighting, patio lights, and garden wiring are extremely prone to water ingress.
Common causes:
water entering junction boxes
cable joins buried underground without waterproof connections
deteriorated conduit or fittings
water pooling near low points in the wiring
Signs:
power trips only at night (when lights switch on)
it trips after prolonged rain
you’ve recently had garden work done
outdoor lights flicker before power trips
3. Wet Extension Leads and Power Boards (Storm Season Classic)
This is one of the most common Brisbane storm mistakes.
If an extension lead or power board is exposed to rain even slightly, it can trip the safety switch instantly.
Common scenarios:
Christmas or outdoor lights still plugged in
outdoor fridge, pumps, or chargers left connected
temporary power use during backyard work
power boards left under patio furniture
Signs:
it trips right after the storm starts
it stops tripping once everything dries out
it trips immediately when you plug something in outdoors
4. Water Ingress into the Switchboard or Meter Box (Serious Risk)
In some Brisbane homes, the meter box or switchboard area can allow moisture entry, especially during wind-driven storms.
Moisture in the switchboard can cause:
corrosion
arcing
nuisance tripping
overheating components
Warning signs:
buzzing or crackling sound near the board
burning smell
visible moisture or condensation in the meter box
discoloured or melted plastic near breakers
This is a serious risk and needs immediate professional attention.
5. Moisture in Roof Spaces or Wall Cavities (Hidden Cause)
Brisbane storms can force water into roof spaces, through cracked tiles, flashing, or older gutters.
If water reaches wiring junctions, lighting points, or downlights, it can cause a fault.
Common triggers:
ceiling leaks
water stains after storms
downlights tripping the circuit
older wiring in ceiling space
Signs:
it trips during or shortly after rain
it trips when you turn on certain lights
it trips more after heavy storms than light rain
you’ve noticed ceiling moisture recently
6. Damaged Underground Cables (Yard Areas & Sheds)
If you have power running to:
sheds
granny flats
pool equipment
outdoor kitchens
external lighting circuits
Then water ingress into underground joints can cause repeated tripping.
Common causes:
old joints not sealed properly
digging or landscaping damage
water pooling where cable runs
cable insulation breakdown over time
Signs:
trips only when it rains heavily
shed or backyard circuits stop working
it trips when external circuits are used
7. Appliance-Specific Faults Triggered by Moisture
Sometimes the problem isn’t your entire electrical system. It’s a specific appliance getting wet.
Common culprits:
pool pumps
spa systems
outdoor fridges
outdoor aircon units
exterior exhaust fans
Signs:
the power trips only when that appliance runs
it trips when the appliance starts
it trips even when everything inside the house is fine
What You Should NOT Do
Avoid resetting the safety switch repeatedly.
Repeated tripping can:
worsen wiring damage
increase corrosion and overheating
damage connected appliances
turn a minor fault into a serious hazard
If it trips more than once, stop using the affected circuit until it’s checked.
When It’s a Safety Emergency (Call Immediately)
Stop using power and call a licensed electrician if you notice:
burning smell near the switchboard
buzzing, crackling, or sparking sounds
water inside the meter box or switchboard
melted or discoloured power points
the safety switch won’t reset
the system trips instantly every time
These signs can indicate active moisture faults or dangerous arcing.
Final Word: Rain Tripping Is a Moisture Fault Until Proven Otherwise
If your power keeps tripping after heavy rain, the safety switch is doing its job protecting you from an unsafe fault.
In Brisbane storm season, the most common causes are:
water in outdoor power points
wet extension leads or power boards
moisture in lighting circuits
water ingress into switchboards or junction boxes
The sooner it’s found, the safer and cheaper it is to fix.
👉 Need a licensed electrician in Brisbane to find the cause safely?
Contact Exclusive Electrical & Air to test the affected circuits, locate the moisture fault, and get your home back to safe operation.