A comprehensive analysis of historical hourly temperature data reveals pivotal insights into the evolving climate dynamics across United States regions, presenting a nuanced understanding that transcends conventional averages. Researchers at North Carolina State University conducted an extensive study investigating temperature variations over the past 45 years, leveraging granular hourly records from 340 weather stations across the contiguous U.S. and southern Canada. Their findings illuminate significant regional disparities in climate change impacts, highlighting critical shifts in the duration of freezing and heat stress conditions with profound implications for ecological systems, agriculture, infrastructure, and public health.
The seminal work underscores the inadequacy of relying solely on average temperature changes when assessing climate impacts. Sandra Yuter, Distinguished Professor of Marine, Earth, and Atmospheric Sciences at NC State and corresponding author, emphasizes the importance of threshold exceedance metrics. “Incremental average temperature increases often mask the real-world consequences of climate change,” Yuter asserts. A modest rise of two or three degrees Fahrenheit may appear trivial for temperate areas averaging 65°F, yet the same increase meaningfully alters conditions near freezing, producing disproportionate ecological and societal effects. This insight directs attention toward the temporal patterns of temperatures crossing key biological and infrastructural thresholds.
The study meticulously analyzed hourly air temperature data extracted from NOAA’s Integrated Surface Database Lite, covering the period from 1978 through 2023. This high-resolution dataset allowed researchers to quantify decadal trends in the cumulative hours per year when temperatures fell below freezing (0°C, 32°F) and when they exceeded heat stress thresholds (30°C, 86°F)—a critical benchmark for plant and animal well-being. Additionally, they evaluated heating and cooling degree hours relative to a baseline of 18°C (65°F), which serves as a proxy for energy demand associated with temperature regulation.
Regional analyses revealed pronounced winter warming in the northeastern United States. Stations located east of the Mississippi River and north of the 37th parallel experienced a loss equivalent to approximately one and a half to two weeks per year of subfreezing conditions relative to early 1980s baselines. This pronounced reduction in below-freezing hours signals diminished frost duration, with wide-reaching consequences for ecosystems dependent on cold periods for lifecycle events, such as dormancy and pest control. It also modifies heating requirements for residential and commercial buildings, with potential secondary impacts on energy infrastructure.
Conversely, substantial increases in heat stress duration emerged in the southwestern United States and southern Texas. Locations within Arizona, New Mexico, southern Nevada, southern California, and southern Texas have accrued roughly one and a half weeks more per year of temperatures exceeding 86°F. This escalation in heat stress interval poses significant risks to agricultural productivity through enhanced evapotranspiration, water stress, and heat-related crop damage. Livestock are similarly impacted, grappling with thermoregulatory challenges that can reduce yield, growth, and reproductive success. The findings thus delineate hotspots where adaptation efforts must prioritize mitigation of thermal extremes.
Intriguingly, the Midwest displayed minimal systematic trends in either freezing or heat stress hours, likely attributable to its inherent climatic variability and transitional geography. This absence of clear directional change accentuates the complexity of detecting climate signals in regions with highly fluctuating temperature regimes. Such variability necessitates improved predictive models and localized data to inform resilient adaptation strategies tailored to variable climates.
Crucially, the research highlights that the duration of temperature extremes — rather than isolated peak values — carries greater ecological and societal weight. Yuter explains, “A maximum temperature of 90°F sustained for six consecutive hours impacts organisms, infrastructure, and energy systems differently than a brief spike lasting only one hour.” This temporal dimension enhances understanding of stress exposure and informs the design of mitigation measures addressing cumulative heat load and cold exposure.
Energy usage patterns mirror these climatic shifts, with many northern areas experiencing a faster decline in heating degree hours compared to gains in cooling degree hours. This evolving energy landscape challenges utility planning, infrastructure investment, and energy policy. The temporal trends in temperature thresholds provide actionable metrics for quantifying future energy demand scenarios and optimizing resource allocation in response to climate change.
The study’s innovative approach integrating high-frequency temperature data enriches the climatology field by complementing traditional daily minimum, maximum, and average temperature analyses. It offers a pragmatic lens for decision-makers, translating abstract average increases into tangible lived experiences reflecting ecological rhythms and human comfort. This granularity facilitates enhanced communication about climate risks, fostering informed community engagement and policy formulation.
Looking forward, these empirical insights equip stakeholders across sectors — policymakers, urban planners, agricultural managers, and public health officials — with vital evidence to tailor climate adaptation efforts regionally. Understanding the spatiotemporal nuances of threshold exceedances enables targeted interventions ranging from modifying crop calendars and livestock management practices to upgrading infrastructure designed for thermal resilience and optimizing energy consumption patterns.
The research underscores the imperative of using hourly temperature metrics as a foundation for more precise climate risk assessments. Such data-driven strategies promise to accelerate adaptation actions responding to ongoing and anticipated climate vulnerabilites. By illuminating distinct patterns of warming and cooling hour shifts, this work charts a course toward more effective, localized climate resilience planning rooted in the realities of everyday temperature fluctuations.
Published in the renowned journal PLOS Climate, this study—entitled “The power of hourly weather data: Observed air temperature climate trends for pragmatic decision-making”—represents a collaborative effort led by former NC State undergraduate Logan McLaurin, with significant contributions from Sandra E. Yuter, Kevin Burris, and Matthew A. Miller. The research was generously supported by the NC State University Provost Professional Experience Program, NASA, the Office of Naval Research, and the Robinson Brown Ground Climate Study donation fund. The detailed analyses therein are poised to influence climate science discourse and practical adaptation policies alike.
By shifting focus from averages to threshold exceedances over time, this work pioneers a more visceral understanding of how regional climates are evolving amid global change. It invites stakeholders to reconceptualize climate change impacts in terms that align with observable, lived conditions, thereby mobilizing pragmatic, evidence-based responses to one of the most pressing challenges of our era.
Subject of Research: Analysis of Historical Hourly Air Temperature Data to Assess Regional Climate Change Impacts
Article Title: The power of hourly weather data: Observed air temperature climate trends for pragmatic decision-making
News Publication Date: November 12, 2025
Web References:
- https://journals.plos.org/climate/article?id=10.1371/journal.pclm.0000736
- http://dx.doi.org/10.1371/journal.pclm.0000736
References:
McLaurin L., Yuter S. E., Burris K., Miller M. A. (2025). The power of hourly weather data: Observed air temperature climate trends for pragmatic decision-making. PLOS Climate. https://doi.org/10.1371/journal.pclm.0000736
Keywords:
Hourly temperature data, climate change, freezing point trends, heat stress thresholds, regional climate impacts, temperature variability, energy usage, climate adaptation, northeastern U.S. warming, southwestern heat stress, NOAA Integrated Surface Database, ecological impacts
