Extreme weather is driving up health care costs for American employers, but most companies don't know by how much, or which of their workers are most at risk.

The Climate Health Cost Forecaster was designed to help you find out.

Developed by Mercer and guided by the National Commission on Climate and Workforce Health — the strategic advisory board behind the Health Action Alliance's Extreme Weather + Work initiative — the Forecaster is a first-of-its-kind tool built to help employers project costs and stay ahead of weather-related risks.

What It Models

The Climate Health Cost Forecaster projects your organization's potential long-term health care costs linked to extreme weather.

It estimates how climate events such as severe heat, poor air quality, hurricanes, and flooding could increase employer-sponsored health care claims costs over the next 10 years.

Results are scaled by employer size, industry, and regional exposure, providing a tailored view of your organization's risks and costs, not just a generic average.

These data-driven insights empower you to make informed decisions to support your people and protect your business.

How It Works

The model integrates climate data, epidemiological research, and Mercer's proprietary health cost modeling to estimate health care costs due to extreme weather. It draws data from the CDC, EPA, FEMA, USDA, Mercer's claims database, and historical and projected trends. Members of the National Commission on Climate and Workforce Health reviewed and guided the methodology.

To run a forecast, you'll need:

• Your organization's industry
• Total number of employees
• The first three digits of four zip codes (MSAs) with the largest employee populations
• Employee count in each of those zip codes
• Percentage of employees in each zip code working in climate-controlled environments
• Expected annual per-employee medical and prescription drug costs (PEPY), if available

The tool is built specifically for U.S.-based workforces, and results focus on employer-sponsored plans; other types may experience different impacts.

Why It Matters

Employers are increasingly on the front lines of weather-related health risks, but most are making decisions without data; only 4% have assessed their extreme weather vulnerability.

The Climate Health Cost Forecaster gives HR, benefits, risk, and health and safety leaders the data they need to build a proactive case for preparedness investment.

If you're ready to go further, Extreme Weather + Work translates insights like these into coordinated plans, policies, and practices to help you support your people and protect your business. Learn more about Extreme Weather + Work and how your organization can get involved.

About Extreme Weather + Work

Extreme Weather + Work is an initiative of the Health Action Alliance. We bring together leaders who rarely sit in the same room and connect them with peers across industries, giving them the research and tools they need to support their people before, during, and after extreme weather. Sign up for our monthly newsletter to stay up to date on our latest events, resources, and recommendations. For deeper support, tools, and a peer community, explore Extreme Weather + Work membership.

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