Extreme Heat

A crowded subway platform in NYC on a hot day

NYC's sweltering subway tunnels might soon provide heat to nearby buildings

The MTA is studying how a Thermal Energy Network could capture extreme excess heat from subway platforms to warm nearby municipal buildings.

August 18, 2026 - Mass Transit

SEPTA train on track in front of Phildelphia city skyline.

Extreme heat forces Amtrak, SEPTA to slow trains

High temperatures affect train tracks, electrical equipment and other key infrastructure.

July 16, 2026 - The Philadelphia Inquirer

Children walking on a wooden walkway over green creek bed in Copenhagen, Denmark.

Copenhagen is losing its cool

In a city long designed to maximize light during dark Scandinavian winters, climate change is forcing the Danish capital to rethink its relationship with the sun.

July 9, 2026 - Emilie K. Adin

Silver Amtrak Acela train on track.

Amtrak cancels over a dozen trains due to extreme heat

The eastern side of the country faces a scorching holiday heat wave.

July 5, 2026 - ABC News

People waiting at a Phoenix light rail station under decorative shade elements.

Cool Routes app plots shady walks in arid Arizona

Alternate routes provided by the app reduced the heat experienced during the walk by an average of 4.5 degrees.

June 16, 2026 - ASU News

A lake harbor with white boats in Martinez Lake, Arizona.

Arizona had its hottest spring in 131 years

Average March temperatures across the state were 12.5 degrees above normal.

June 7, 2026 - KJZZ

Man installing or repairing mini split air conditioning unit on white wall.

The Pacific Northwest is an unlikely front in the fight for cooling

A 2021 heat dome killed over 250 people in the Pacific Northwest, bringing into sharp focus the potential of extreme heat to have deadly consequences even in historically cool climates.

May 31, 2026 - Heatmap

Two people walking on wide sidewalk shaded by mature trees in Malaga, Spain.

Green blocks are up to 4 degrees cooler than treeless streets

The difference in temperature created by urban trees can translate to as much as 40% less excess heat.

May 7, 2026 - Green Spaces Coalition

Phoenix, Arizona skyline against the sunset.

Study: Pavement covers 40% of Phoenix

A new study reveals how ultrafine particles emitted by pavement worsen air quality.

April 28, 2026 - ASU News

A wide-angle overview of a busy street at Downtown Austin, with modern skyscrapers towering in background, on a bright sunny Autumn day.

Austin uses satellite data to find gaps in its tree canopy

Layering tree data, heat risk and demographics information is helping the city implement its Climate Equity Plan.

April 27, 2026 - Smart Cities Dive

Street in Seattle, Washington with large trees shading sidewalk with glass storefront.

Washington Urban Forestry Program Faces 'Existential' Budget Cut

A proposed budget eliminates funding for a key urban forestry program that funds greening efforts across the state.

March 2, 2026 - The Urbanist

Sun rising over downtown Los Angeles with tall palm trees visible in foreground. Image is bright orange-red indicating extreme heat.

LA County Adopts First Heat Action Plan

LA County has adopted its first Heat Action Plan, a long-term, people-centered framework to reduce heat risks, protect public health, and adapt communities, homes, and public spaces to a hotter and more dangerous climate.

February 8, 2026 - LAist

Window AC units on a brick building.

New NYC Law Requires Landlords to Provide AC Units — But not in Public Housing

Building owners are required to install AC units for tenants who request them in the next four years, but tenants are on the hook for electricity costs.

January 23, 2026 - Brick Underground

Home perched on steep cliff almost falling due to erosion.

Zillow Deleted Climate Risk From California Listings. This Climate Expert Wants to Bring it Back.

While difficult to estimate for individual homes, experts argue that home buyers should have access to data about flood and wildfire risk, extreme heat, and other climate hazards in the area.

January 22, 2026 - Inside Climate News

Man walking through snow in city with snow falling.

“Nobody Walks Here. It’s Too Hot or Cold or Wet or Dry.”

How much does weather actually play into the choices people make about their travel behaviors?

November 10, 2025 - Jarrett Walker

Woman sitting in subway car holds up small portable fan to cool herself.

Temperatures in Subways Can Soar Well Above 100. What Some Cities are Doing About it.

Extreme heat can be even more dangerous in confined subway cars and stations.

October 31, 2025 - Wired

Heat map of two different neighborhoods in Houston, Texas.

Study: Houston’s Vacant Lots Worsen Heat Island Effect

Paved lots and abandoned buildings can raise surrounding surface temperatures as much as 20 degrees, according to a new study.

October 8, 2025 - Texas A&M University

Dozens of cars parked in rows in an open-air parking lot.

Study: Parked Cars Significantly Increase Urban Heat Island Effect

Dark-colored cars in particular can raise the surrounding air temperature by as much as 3.8 degrees Celsius.

August 17, 2025 - Carbon Copy

Sun rising over downtown Los Angeles with tall palm trees visible in foreground. Image is bright orange-red indicating extreme heat.

LA County Adopts Maximum Indoor Temperature Ordinance to Protect Renters from Extreme Heat

LA County has adopted an ordinance capping indoor temperatures in rental units at 82 degrees Fahrenheit in unincorporated areas, aiming to protect renters from extreme heat while providing phased compliance and support for small landlords.

August 10, 2025 - Random Lengths News

Poway, California

Extreme Heat Prompts Trail Closures and Safety Warnings in San Diego

San Diego County has closed three hiking trails for August due to extreme heat, urging hikers to stay safe with proper planning, hydration, and early starts.

August 4, 2025 - CBS8

FREE Course: Walkable City 1: Why Walkability?

After describing his path towards focusing on walkability as the essence of good planning, Jeff Speck marches through his five principal reasons for making more walkable places.

Reinventing Malls: Planning Alchemy—Turning Gray Fields Into Gold

The course focuses on the opportunities and imperatives that shape reinvention of mall sites.

Senior Planner

City of Thousand Oaks

Community Development Director

City of Wisconsin Rapids

Professor of Urban Planning

Harvard University Graduate School of Design

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