While other cities face increased risk of hurricanes, wildfires and drought, climate change is projected to reshape life in Chicago mainly through extreme heat and precipitation. And though urban flooding has wreaked havoc on Chicago homeowners, particularly on the South and West sides, heat is far more deadly.
Chicagoans already know that some communities are hotter than others; as the saying goes, it’s cooler by the lake. But heat also varies across cities in more complex ways, largely because of differences in the built environment. Mapping can help identify hotter communities and lead to remedies that reduce temperatures.
To provide Chicagoans access to temperature trends in their communities, the Tribune partnered with researchers at Boston University’s Center for Climate and Health to create a searchable map showing the average summer surface temperature for each census block group in the city, along with information on the race and ethnicity of residents. Block groups are clusters of blocks that the Census Bureau uses to present population data; each typically contains between 600 and 3,000 people.
The map shows land surface temperatures, which are more extreme than the air temperatures cited in weather reports. But these measurements, collected via satellite, made it possible to analyze disparities in heat exposure across the city.
The Tribune and Boston University found that Latino residents disproportionately shoulder the burden of Chicago’s heat disparities, while white residents disproportionately benefit from living in areas with the coolest average temperatures. Census estimates indicate that more than 300,000 people live in areas that are hotter than 90% of the rest of the Chicago, or an estimated 5 to 10 degrees warmer than the city average. These hotter areas are predominantly on the Southwest Side.
Readers can search the temperature map below for any address in the city, or just zoom in and click for more information:
Heat in Chicago: Explore how surface temperatures vary
Search your address or zoom in and click to see temperature, race and ethnicity statistics
Source: Chicago Tribune and Boston University School of Public Health analysis of U.S. Geological Survey Landsat-8 and Landsat-9 satellite data, 2013-2022; U.S. Census Bureau’s 2021 American Community Survey. Map by Jason Rundle, Boston University School of Public Health’s Center for Climate and Health, using geography from the City of Chicago Data Portal and U.S. Census Bureau.
In Illinois, the National Weather Service issues an extreme heat advisory when the heat index — a measure combining air temperature and humidity — is expected to reach at least 105 degrees and not dip below 75 degrees in the evening. Advisories set in motion the city’s Office of Emergency Management Communications heat plan and escalate into warnings if the heat index climbs even further.
City agencies promote the use of six official cooling centers and an array of other air-conditioned public locations, such as libraries, during heat advisories. But the Tribune’s Boston University research partners found that substantial swaths of the city’s most vulnerable communities, with the hottest average surface temperatures, have no access to public cooling within walking distance of a half-mile.
Those high-need areas are shown on the map below in red. Search the map further to explore the locations of cooling resources:
Cooling resources in Chicago
Search your address or zoom in and click to see resources available
Source: Boston University School of Public Health analysis of U.S. Geological Survey Landsat-8 and Landsat-9 satellite data, 2013-2022; Centers for Disease Control Social Vulnerability Index; City of Chicago Cooling Centers. Map by Jason Rundle, Boston University School of Public Health’s Center for Climate and Health, using geography from the City of Chicago Data Portal and U.S. Census Bureau.
More resources
Chicagoans can register for the city’s Emergency Alert System at NotifyChicago.org and request wellness checks on at-risk family members, friends and neighbors by either calling 311, visiting 311.chicago.gov or downloading the CHI311 app. At heat.gov, the federal government’s National Integrated Heat Health Information System provides information on heat illness and tips for staying safe, including en español.
As that site notes: Certain groups face increased risk of heat stress for a variety of reasons, some better known than others. But heat illness can happen to anyone. Athletes and outdoor workers are more exposed to heat than office workers, for instance. Children and seniors are particularly vulnerable, and pregnancy and certain medical conditions also increase risk. Low-income communities and people experiencing homelessness are also disproportionately affected, given a lack of resources to recover from heat exposure and often greater exposure to pollutants, which exacerbates heat’s effects.
Staying in sufficiently air-conditioned spaces is the surest means to stay safe during extreme heat.
Symptoms of heat stroke, a potentially fatal form of heat illness that requires emergency treatment, include dizziness, heavy sweating, confusion and loss of consciousness. If you think someone might have heatstroke, call 911 immediately, move them to a cooler place, loosen their clothing and remove any extra layers, and cool them with water or ice in whatever way is available, the Mayo Clinic notes, such as a cool bath if indoors or, if outdoors, misting with cool water or placing cool, wet towels or ice packs on the person.
Symptoms of heat exhaustion, a milder form of heat illness that can escalate to heat stroke if a person is not moved to a cooler area, also include dizziness and heavy sweating in addition to nausea and fatigue. People experiencing heat exhaustion should also loosen clothing, sip water and seek medical care if symptoms don’t improve.
