Heat Domes Cause Record Temperatures in US and Canada

Heat Domes Cause Record Temperatures in US and Canada

In 2025, the United States and Canada experienced unprecedented heatwaves due to a phenomenon known as a "heat dome." This weather event trapped hot air under a high-pressure system, leading to record-breaking temperatures and severe consequences for both countries.

What is a Heat Dome?

A heat dome occurs when a high-pressure system stalls over a region, trapping warm air beneath it. This creates a "lid" effect, preventing the hot air from dissipating and causing temperatures to soar. The 2025 heat dome was particularly intense, with temperatures reaching nearly 50°C (122°F) in some areas.

Impact on the US and Canada

The heat dome affected western Canada and the US Pacific Northwest, shattering previous temperature records. In Canada, the village of Lytton, British Columbia, recorded temperatures of 49.6°C (121.3F), a new national record. The extreme heat also triggered wildfires, destroying 90% of Lytton and displacing residents.

In the US, cities like Portland, Oregon, and Seattle, Washington, saw temperatures exceed 46°C (115°F). The heatwave led to hundreds of deaths, strained infrastructure, and forced the closure of schools, vaccination centers, and public transport.

Climate Change Connection

Experts link the increasing frequency and intensity of heat domes to climate change. Rising global temperatures and changing weather patterns create ideal conditions for these extreme events. The 2025 heat dome serves as a stark reminder of the urgent need for climate action.

How to Stay Safe

Authorities advised residents to stay hydrated, avoid outdoor activities during peak heat, and seek air-conditioned spaces. Cooling centers were set up to provide relief, especially for vulnerable populations.