The State Climate Summaries were created to meet a demand for state-level information following the publication of the Third National Climate Assessment (2014). The goal was to provide more granular information that could assist decision-makers in government and the private sector, although the summaries have since reached a much broader audience. The first edition of the summaries was published in 2017, the second in 2022. This third version presents an updated summary for each state with the latest information on both observed changes—including long-term trends and extreme weather events—and projections of potential future trends.
Each state’s summary is available on this website and as a downloadable PDF. High-resolution figures, slide decks, and lists of observing stations used in the historical analyses can be found on the Downloads page alongside the PDFs.
Key updates and improvements since the last version of State Climate Summaries include the following:
More up-to-date data: Most observed figures and associated text are now based on data through the end of 2024 (the previous summaries had data through 2020).
Recent extreme events: Many notable climate and weather events from recent years have been added.
Enhanced communication: Key Messages and other sections of text have been revised to reflect updated data and to enhance both clarity and consistency. Website design and functionality have also been improved, increasing accessibility.
Updated models: Projected changes are now based on CMIP6 and the SSP-RCP scenarios (rather than CMIP5 and the older RCP scenarios).
Broader scenario ranges: Figures showing projected temperature trends now feature three scenarios—lower, intermediate, and higher—rather than two, in order to explore a wider range of potential future outcomes. In addition, precipitation projection maps now use the intermediate (rather than high) scenario.
New sea level projections: Sea level and tidal flooding scenarios have been updated based on the 2022 NOAA Sea Level Rise Technical Report, and observed and projected sea level analyses are now shown at the US and state (rather than global) levels.
Improved metadata: More comprehensive figure metadata is presented to allow for full traceability and transparency of data and methods.
New data visualization tool: The summaries are concise and therefore include only a limited set of figures showing the metrics most relevant to each state. The new web-based Data Explorer tool—developed in collaboration with the National Environmental Mapping and Applications Center at UNC Asheville—allows users to access a full suite of temperature and precipitation metrics for all states, as well as data at regional and national scales. The tool also provides data for a wider range of scenarios for temperature and precipitation projections.
Descriptions of historical climate conditions for each state, as well as of notable extreme events, are intended to provide context for the assessment of recent changes and potential future impacts. Information on these historical conditions is based on an analysis of core climate data (primarily from NOAA sources). Climate experts from around the country—in particular, staff members from the NOAA Regional Climate Centers (RCCs) and from state climatology offices—helped prioritize, describe, and contextualize the most significant climate conditions in each state.
The future climate scenarios are intended to provide a set of climate conditions that can inform analyses of potential impacts of climate change. The scenarios are not intended as predictions, as there are no probabilities for their future realization attached. Instead, they simply represent an internally consistent climate picture under certain assumptions about the future pathway of greenhouse gas emissions and other human activities (such as land-use change, aerosol emissions, and socioeconomic factors). “Internally consistent” means that the relationships among different climate variables and the spatial patterns of these variables derive directly from the same set of climate model simulations and are therefore physically plausible. The future climate scenarios are based on global climate model simulations. No regional climate model simulations or downscaled datasets were used in these state climate summaries.
For more information on historical data, scenarios and climate projections, analysis methods, and more, please see the Technical Details and Additional Information page as well as the metadata for individual figures (accessed by clicking the metadata button at the top right of each figure).
The State Climate Summaries are produced by the North Carolina Institute for Climate Studies (NCICS), which is part of North Carolina State University. NCICS is based in Asheville, North Carolina, where it is co-located with the headquarters of NOAA’s National Centers for Environmental Information (NCEI).
Primary funding for NCICS comes from NOAA for operation of the North Carolina location of the Cooperative Institute for Satellite and Earth System Studies under Cooperative Agreements NA19NES4320002 (through June 2025) and NA24NESX432C0001T101 (from July 2026). The initial version of State Climate Summaries (2017) was supported through a similar collaborative research agreement with NOAA, known as the Cooperative Institute for Climate and Satellites.
The first version of the State Climate Summaries, released in 2017, was developed by NCICS staff, with significant contributions from staff at NCEI and the RCCs, as well as from state climatologists around the country. The 2017 summaries underwent an anonymous peer review, with at least two expert reviewers for each state. The 2022 summaries were revised and reviewed by staff at NCICS, NCEI, and the appropriate RCC, as well as, in most instances, by the relevant state climate office.
For this new version, each state’s summary was updated by NCICS staff and reviewed by the appropriate RCC. The authors listed in the recommended citations for the 2025 summaries are NCICS staff members, reflecting the significant updates they made to this version. However, much of the content can be traced back to the previous versions; names of authors of these earlier versions can be found in the 2022 version of the summaries.
Expert review of the 2025 State Climate Summaries by the RCCs was coordinated by NCEI’s Tamara Houston. NCEI’s Communications and Outreach Branch provided further assistance with layout and design. See the individual state pages for additional information about contributors.
For questions related to information, data, and methods used in the State Climate Summaries, please email info-state-summaries@ncics.org.
To provide feedback on the value and utility of the State Climate Summaries, please email scs_engagement@ncics.org.