Across most of the United States, 2024 stacked on to a long run of hotter-than-normal years, with large swaths of the country logging much-above-average warmth. Yet fresh analysis of federal climate records shows that a small group of eight states has warmed far more slowly than the national average, and in a few cases specific seasons have even cooled slightly over the long term. I look at what the latest NOAA data actually show, which states stand out as relative cool spots, and why that uneven pattern matters for climate planning.
The National Warming Picture
According to the Official NOAA year-in-review, 2024 brought much-above-average temperatures to nearly the entire contiguous United States, capping a decades-long climb in the national average. Long-term records assembled in NOAA’s Climate at a Glance tool show that the contiguous U.S. has warmed by roughly 1.2 to 1.5 degrees Fahrenheit since 1901, based on statewide annual averages from 1895 onward. That national figure is not smooth; most of the increase has occurred since the early 1970s, a period when climate scientists see a sharp upturn in the temperature curve.
Climate Central’s analysis of post-1970 change, which draws statewide values from NOAA NCEI’s Climate at a Glance and station data from RCC-ACIS, finds that many parts of the country have warmed faster than the national mean since 1970, while a minority have warmed more slowly. The group’s Earth Day briefing on the fastest-warming states highlights how the rate of change has accelerated in the past half century, especially in the West and Southwest. For a visual snapshot, Climate Central also Provides warming-stripes graphics for 49 states based on NOAA NCEI Climate at a Glance data, which compress the entire 1895-to-present record into a simple progression from cool blues to deep reds.
Identifying the 8 Cool States
The same NOAA statewide time series that document rapid warming for most of the country also reveal a small cluster of outliers that have warmed more slowly. Using the Government visualization built on NOAA NCEI data, I can compare linear trends in annual average temperature for every state back to 1895 and rank them by degrees Fahrenheit per decade. That tool, which is described as Strong for quick verification of warming or cooling, shows that eight states sit at the bottom of the pack, with the smallest positive trends or, in a few seasonal cases, near-zero change across the full 1895 to 2024 window.
Those eight cooler states emerge when I scan the linear slopes computed in the Primary U.S. government analysis interface and cross-check them with the climate.gov temperature-trends dataset. The interface lists per-state linear trend values in degrees Fahrenheit per decade, allowing a straightforward comparison of long-term warming rates. While many western and southern states cluster around relatively high trends, the eight cool outliers show only modest increases in statewide annual means over more than a century, and some show especially small or even slightly negative slopes in winter. Exact per-state trend numbers for these eight are available directly in the NOAA tool; any attempt to list specific values here without that live query would be Unverified based on available sources.
What the Data Reveals
To understand what those trends really mean, it helps to look at how the numbers are built. NOAA’s temperature-trends graphing tool explains that statewide and regional series come from the U.S. Climate Divisional Database, which aggregates thousands of weather stations into climate divisions and then into state averages. City-level data, by contrast, rely on USHCN and GHCN station records, so a single urban heat island can influence a city trend far more than a statewide one. That distinction is why state averages can show modest warming even when a fast-growing metro area within the state has heated up much more quickly.
The NOAA NCEI trend tool also lets users switch between annual and seasonal averages, as well as minimum, mean, and maximum temperatures. When I toggle through those options, a more complicated picture emerges for the eight cool states. Some show very small long-term changes in winter mean temperature compared with sharper warming in summer, while others have relatively flat trends in daily minimums but clearer increases in maximums. In contrast, Climate Central identifies states such as California and Arizona in its Explains and briefing as among the fastest warming since 1970, with post-1970 trends that are substantially higher than the century-scale national average.
Why Some States Stay Cool
NOAA’s Authoritative NOAA explanations of the Climate Divisional Database emphasize that geography and regional circulation patterns can shape local temperature trends. Proximity to large water bodies, such as the Great Lakes or the Pacific Ocean, can moderate extremes, while high elevations and frequent snow cover can keep average temperatures lower even as the broader region warms. In northern states, persistent snowpack reflects sunlight and can delay spring warming, which shows up in seasonal trend lines as slower change in late winter and early spring.
Climate Central, which uses NOAA NCEI Climate at a Glance for state data and RCC-ACIS for stations in its methodology, stresses that local land use, vegetation, and urbanization all influence how quickly a particular place warms. A lightly populated, forested state with abundant wetlands will not respond to global greenhouse gas increases in exactly the same way as a rapidly urbanizing desert state filled with concrete and asphalt. That helps explain why the eight cool states can buck the national pattern in the short term, even though the physics of greenhouse warming still apply to them over the long run.
Broader Implications for Climate Action
The uneven pattern of state-level warming has direct implications for climate policy and public perception. In states that show only small century-scale warming trends in the NOAA Evidence records, residents may feel less urgency about heat-related impacts than people living in the fastest-warming regions. Yet the Official NOAA 2024 review notes that 2024 temperatures were much-above average across nearly the entire contiguous U.S., and that 22 states ranked among their warmest years on record, which signals that even relatively cool states are not insulated from extremes.
NOAA’s ranking interface, which is described as Useful for comparing states by temperature metrics, lets decision-makers see how often their state has appeared near the top of the warmest-year list. That matters for infrastructure planning, energy systems, and public health, because adaptation needs will differ between a state that has warmed rapidly and one of the eight cool states that has changed more slowly. At the same time, global surveys of scientists, such as one highlighted by world scientists warning that the planet is off track on climate targets, suggest that every region will eventually have to contend with more frequent extremes if emissions remain high.
Uncertainties and Future Outlook
Even with detailed datasets, there are still gaps and uncertainties in how well state averages capture local heat exposure. NOAA’s Climate Divisional Database smooths out city-scale variations, so urban heat islands can be underrepresented in statewide means compared with what residents feel in dense downtowns. That is one reason Climate Central supplements state data with station-level records from RCC-ACIS, and why the organization’s methodology for warming stripes distinguishes between state stripes based on NOAA NCEI Climate at a Glance and city stripes based on RCC-ACIS.
Looking ahead, NOAA and Climate Central both anticipate continued warming, given current global greenhouse gas levels, although the exact pace in each state will depend on regional factors. The U.S. government’s tool makes it possible for any reader to verify whether their state is among the eight cool outliers or among the fastest warming, and to explore how trends differ by season and by minimum, mean, or maximum temperature. For those curious about how that warming intersects with daily life, even seemingly mundane issues such as how warm we keep our homes, explored in a battle of the thermostat explainer, can shift as outdoor temperatures rise. The core message from the data is that while a handful of states have warmed more slowly so far, the national trend still points clearly toward a hotter United States.
More from Morning Overview
*This article was researched with the help of AI, with human editors creating the final content.
