Why Your GFCI Trips When It Rains
If your GFCI outlet trips during or after rain, moisture is getting into the outlet, wiring, or an outdoor fixture on the same circuit. GFCIs are designed to detect even tiny amounts of leakage current, so any water intrusion will cause an instant trip.
1. Moisture Inside the Outdoor Outlet
Outdoor outlets are exposed to humidity, rain, and condensation. If the weatherproof cover is cracked, missing, or left open, water can enter the outlet box and trigger the GFCI.
If the outlet won’t reset afterward, see GFCI won’t reset.
2. Water Entering the In-Use Cover
Even “weatherproof” covers can fail if they’re old or not fully sealed. Water can drip inside and reach the receptacle, especially during wind-driven rain.
3. Moisture in the Wiring or Conduit
Outdoor wiring runs through conduit that can crack, separate, or fill with condensation. When water reaches the conductors, the GFCI detects leakage and trips immediately.
Learn more about wiring issues in loose wiring symptoms.
4. Wet Light Fixtures or Outdoor Equipment
GFCIs often protect multiple downstream devices. If any outdoor light, pump, or outlet gets wet, the main GFCI will trip — even if the problem isn’t at the GFCI itself.
5. Damaged or Cracked Outlet Box
Older outdoor boxes can crack or separate from the wall, allowing water to enter. Even small gaps can cause moisture buildup that trips the GFCI.
6. Faulty GFCI Outlet
GFCIs wear out over time. If the device is old, it may become overly sensitive to humidity or temperature changes and trip more easily.
7. Water Entering Through the Wall
Sometimes the moisture isn’t entering the outlet directly — it’s coming through the siding, stucco, or brick. Water can run down the wall and into the box from behind.
When the Issue Becomes Dangerous
Stop troubleshooting and call an electrician if you notice:
- Repeated tripping even after drying the outlet
- Burning smell or discoloration
- Visible water inside the outlet or box
- Crackling or popping sounds
When to Call an Electrician
If the GFCI trips every time it rains, moisture intrusion is almost guaranteed. A licensed electrician can test the circuit, inspect outdoor wiring, and replace damaged outlets or covers to prevent future trips.
Helpful Resources
- Symptoms Index – Quickly find your electrical issue.
- FAQ – Answers to common electrical troubleshooting questions.
- Electrical Safety Foundation International – Trusted electrical safety information.