Interactive Story Map · Austin, Texas
On a summer afternoon, the ground in some Austin neighborhoods runs nearly 10°F hotter than in others just minutes away. This is a measured map of where the city's surface burns hottest — why, who it falls on, and what can be done.
All temperatures here are land surface temperature from satellite thermal imagery — the heat of roofs, roads, and ground, which on a summer afternoon runs far hotter than the air. That surface heat is the engine of the urban heat island.
Each neighborhood here is shaded by its average land surface temperature across three recent summers (2022–2024), measured from Landsat thermal imagery. Cooler blues, hotter reds.
These six were chosen to span the city — east and central, north and south, hills and flats — but the patterns you will see were measured across all 65 of Austin's neighborhood planning areas. Click any neighborhood to see its numbers.
Replace trees and soil with rooftops, roads, and parking, and the ground stops breathing and starts storing heat. Dark, dense surfaces absorb the sun all day and radiate it back late into the night. The result is a measurable temperature gap between the built city and the countryside around it — the urban heat island.
Austin's own environmental office is blunt about the stakes: urbanization alone, even before climate change, could raise the city's temperatures by as much as 7°F by 2050.
"Urbanization alone, without projected climate change, could drive urban temperatures up by 7°F by 2050." — City of Austin, Freezing the Urban Heat Island Effect
The hottest neighborhoods cluster in the urban core and east side — dense, paved, historically industrial. The coolest sit in the leafier, hillier areas. Across these six, the gap between hottest and coolest ground is nearly 10°F of surface temperature.
Switch the map to tree-canopy cover and the pattern nearly inverts. Across all 65 neighborhoods, more canopy means lower surface heat — a strong, consistent relationship. Trees cool in two ways: they shade surfaces before the sun can load them with heat, and they release water vapor that cools the air directly.
This is not just an Austin quirk. A 2025 global study of thermal and ground-station data found canopy's cooling effect is large and dose-dependent.
A 10% increase in tree canopy lowers local air temperature by about 0.8°C; a 30% increase by as much as 1.5°C. — npj Urban Sustainability (2025)
Impervious surfaces — roofs, roads, parking lots — are the other half of the story. They absorb solar energy and re-radiate it for hours. The most paved neighborhoods are the hottest, and the relationship is nearly as strong as canopy's, in the opposite direction.
Canopy and pavement are two sides of the same coin: where one rises, the other tends to fall. Together they describe most of the variation in where Austin's surface runs hot.
Heat in Austin is shaped first by the physical landscape. Income plays a real but weaker role: lower-income neighborhoods tend to run hotter, though the relationship is moderate and has clear exceptions.
The exceptions matter. Central East Austin is among the hottest in the city despite rising incomes from gentrification, while leafy, affluent Zilker stays cooler. The deeper pattern is historical: in Austin, as in many US cities, decades of segregation and disinvestment left lower-income and minority neighborhoods with far less tree canopy.
Affluent Westlake (median income $238k) sits under 69% tree canopy; the St. Johns neighborhood ($41k) under just 21%. — Axios Austin, citing the City's State of Our Environment report (2024)
Today's heat map is the imprint of yesterday's choices: where roads were laid, where trees were kept or cleared, which neighborhoods were invested in and which were not. Surface heat is, in part, a century of land-use decisions made visible.
The trajectory is the harder part. Central Texas is projected to warm by roughly 3 to 7°F over the next 50 to 100 years, and that rise stacks on top of the urban heat island, not beside it. The hottest, least-shaded neighborhoods today are the ones with the least buffer against the heat coming tomorrow.
"Climate change projections show Central Texas' climate gradually becoming hotter, with temperatures rising three to seven degrees over the next 50 to 100 years." — City of Austin
The same finding that explains the problem points to the fix. Because heat tracks canopy and pavement so tightly, the most effective interventions are physical and local: plant and protect trees, and break up heat-storing pavement.
The evidence says targeting matters. Cooling does the most good where it is hottest and least shaded today — which, given the history, means directing canopy investment into lower-income, low-canopy neighborhoods rather than spreading it evenly. Cool-pavement coatings, reflective roofs, and shaded transit stops add further relief in the most built-up cores.
The data turns a vague goal into a specific, mappable question a city can act on: not "plant more trees," but where would a tree do the most good?
This analysis turns satellite thermal imagery, land-cover data, and census income into one actionable picture: where Austin's surface runs hottest, why, who lives there, and where intervention would matter most. The strongest signal is also the most hopeful — the thing driving the heat, canopy and pavement, is the thing a city can actually change.
Data & methods. Land surface temperature: median of clear-sky Landsat 8 & 9 thermal scenes (June–August 2022–2024), processed in Google Earth Engine. Tree canopy and impervious surface: NLCD / USFS products, zonal means per neighborhood. Boundaries: City of Austin Neighborhood Planning Areas (65, dissolved from the open-data layer). Income: U.S. Census ACS 2018–2022 (table B19013), area-weighted from census tracts to neighborhoods via a PostGIS spatial join (tracts reprojected NAD83→WGS84; geometries validated before overlay). Correlations computed across all 65 planning areas (n = 65). Charts built with Chart.js; map with Leaflet. Full methodology →