Tuesday, December 23, 2025

Heavy Rain Forecast Prompts Safety Reminders for Outdoor Holiday Lights

With a powerful rainstorm expected to bring heavy rain and strong winds to Pasadena and Altadena this week, residents with outdoor Christmas light displays are being urged to take precautions to reduce the risk of electric shock and fires.

Forecasters say rain is expected to begin Tuesday, with heavier rainfall developing Tuesday night into Wednesday as a strong Pacific storm system moves through the region.

Electrical safety guidance warns that these conditions increase the likelihood of water reaching outdoor electrical outlets, plugs and extension cords, particularly where connections sit on the ground or outlets are exposed to wind-driven rain. Moisture at these points increases the risk of short circuits and electrical arcing, and raises the risk of shock when electrical devices are handled in wet conditions.

Safety guidance consistently notes that the safest option during periods of sustained heavy rain is to turn off and unplug outdoor lighting displays until conditions improve.

For households that keep lights installed and on during the storm, safety guidance emphasizes the use of outdoor-rated equipment and purpose-built weather protection rather than improvised methods.

Outlets and plug connections are key risk points

Outdoor electrical outlets are often the most vulnerable part of a holiday lighting display. Electrical standards for wet locations require outlets to be protected by listed enclosures designed to remain weatherproof even when a cord is plugged in. These are commonly known as “while-in-use” or “bubble” covers and are designed to shield receptacles from rain driven by wind.

Where outlets are not fully enclosed while in use, moisture intrusion becomes more likely during storms.

Ground-fault circuit interrupter protection is also strongly recommended for outdoor electrical use in wet conditions. GFCI devices are designed to shut off power automatically when a ground fault occurs, helping reduce the risk of electric shock.

Plug-to-socket connections between extension cords and light strings present another common vulnerability during rain. Safety guidance advises keeping these connections elevated off the ground and routed so water drains away from the plug, reducing the chance that water will pool at the connection point.

Purpose-built cord-connection enclosures—sometimes described as watertight safety capsules, cord locks or twist-and-seal devices—are designed specifically to protect plug joints from rain and moisture and are identified as the preferred method for protecting outdoor connections.

Improvised plastic wrapping not recommended

Electrical safety guidance from electrical safety and standards organizations does not recommend improvised coverings.

Research cited in safety materials notes that household plastic wrap and similar materials are not rated, listed or tested for electrical protection in wet locations. Improvised wrapping can trap moisture and heat at electrical connections, increasing the risk of electrical arcing rather than preventing it.

Safety guidance instead points to the use of listed, outdoor-rated enclosures and cord-connection protection designed specifically for wet conditions as the preferred approach.

Before, during and after the storm

Ahead of the heaviest rain, residents are advised to review outdoor lighting setups and ensure that only lights and extension cords labeled for outdoor use are installed outside. Connections should be elevated and protected, and outlets should be properly enclosed while in use.

During periods of heavy rain, electrical plugs and cords should not be handled with wet hands or while standing on wet ground. If rain reaches outlet areas or plug connections, turning off the display and unplugging it is identified as the safest response.

After rainfall, wet connections should be allowed to dry before power is restored.

Bottom line

As severe weather moves through Pasadena and Altadena this week, electrical safety guidance emphasizes prevention: outdoor-rated equipment, GFCI protection, listed weatherproof outlet covers and purpose-built cord-connection enclosures. Turning off and unplugging outdoor lights during the heaviest rain remains the most effective way to reduce risk.