Satellite view of hurricane Hugo in 1989
Extreme events such as heat waves, droughts, tornadoes, and hurricanes have affected the United States since the dawn of time. NCDC provides a variety of information detailing these events categorized by type of event.
This tool lists and maps records tied or broken on a given date for weather stations across the 50 United States. Records are distinguished as daily (largest/smallest for that day on the calendar), monthly (largest/smallest value during that month) or all-time (largest/smallest value ever observed at that station). Summary information for recent periods (year-to-date, month-to-date, last 30 days) is provided in tabular format.
Climate Extremes Index
This index charts the occurrence of specific extreme events over time since 1910. In most cases, extreme events are defined as lying in the outermost (“most unusual”) ten percent of a place’s history. Analyses are available at the national and regional levels.
The U.S. Billion-dollar Weather/Climate Disaster report provides readers with an aggregated loss perspective for major weather and climate events from 1980 to present. This report provides information such as economic loss, deaths and other impacts for numerous weather and climate disasters including: tropical cyclones, floods, droughts / heat waves, severe local storms (e.g., tornado, hail, straight-line wind damage), wildfires, crop freeze events and winter storms.
National Climate Extremes Committee
The National Climate Extremes Committee (NCEC) was established in 1997 to assess the merit of extreme events and provide a recommendation to NOAA management regarding the validity of related meteorological measurements. The NCEC is also responsible for disseminating NOAA's recommendation of the event and coordinating any media inquiries with the appropriate public affairs offices. The NCEC is chaired by a representative from NCDC, with additional representatives from the National Weather Service and the American Association of State Climatologists.
State Climate Extremes Committee
The State Climate Extremes Committee (SCEC) is an ad hoc committee established to evaluate the climatological records of individual states. The program was created in 2006 to provide a comprehensive evaluation of observations, which may have tied or exceeded existing statewide all-time record values. Climatic extremes are an important component of a location's climatology and are used for quality controlling meteorological observations, setting engineering limits, and helping authorities to develop climate-related safety plans, among other things.
Special Reports on Extreme Climate Events
Some significant climate events are subject to a deeper analysis than is possible on NCDC’s operational monitoring time scales. This section catalogs significant events beginning in the late 1990s and details specific storms or events including, but not limited to: hurricanes, droughts, wildfires and flooding.
The Global Hazards report provides summary information related to notable and significant weather and climate events around the world. These reports often draw upon real-time information from external sources (international bodies, relief organizations, media reports), so they cannot be considered comprehensive and complete. When possible and appropriate, additional data and analysis is performed to provide stronger historical context for the reader.
International Best Track Archive for Climate Stewardship (IBTrACS)
IBTrACS provides tropical cyclone best track data in a centralized location to aid understanding of the distribution, frequency, and intensity of tropical cyclones worldwide.
NCDC monitors and provides access to a host of drought-related information including the current U.S. Drought monitor map, the National Integrated Drought Information System Drought Portal, U.S. Palmer Drought Indices, the U.S. Standardized Precipitation Index, and U.S. State and Regional Precipitation Status.
The U.S. tornado climatology page, which was developed in coordination with NOAA’s Storm Prediction Center, examines tornado activity across the United States on both the temporal and spatial scale. The contiguous United States is the most active tornado region in the world, with an average of 1,253 tornadoes occurring annually. The information and data included in the U.S. tornado climatology page serves as a baseline for comparison of current tornado activity against what has happened in the past, providing a complete historical perspective.
U.S. Snow Climatology
Here you can access snowfall and snow depth statistics for several thousand non-airport stations in the National Weather Service (NWS) Cooperative (COOP) Network across the contiguous U.S. and Alaska. These snow climatologies enable NOAA to better respond to user requests for snow information for use in economic and engineering decision-making, and provide the Federal Emergency Management Agency (FEMA) with an objective basis for declaring federal snow disasters.
Regional Snowfall Index
NCDC produces the Regional Snowfall Index (RSI) for significant snowstorms that impact the eastern two thirds of the United States. The RSI ranks snowstorm impacts on a scale from 1 to 5, similar to the Fujita scale for tornadoes or the Saffir-Simpson scale for hurricanes.
Northeast Snowfall Impact Scale
The Northeast Snowfall Impact Scale (NESIS) characterizes and ranks high-impact Northeast snowstorms. This index differs from other meteorological indices in that it uses population information in addition to meteorological measurements. Thus, NESIS gives an indication of a storm's societal impacts.
Severe Weather Data
Links to NCDC's severe weather data, which includes the Storm Events Database, the Severe Weather Data Inventory (SWDI), and the International Best Track Archive for Climate Stewardship (IBTrACS). These databases provide online access to files for storm and hurricane data in formats that include Shapefiles (for GIS), KMZ (for Google Earth), CSV (comma-separated), and XML.
North American Climate Extreme Monitoring (NACEM)
The NACEM product was developed to provide an accessible analysis tool to improve understanding of observed changes in extreme climate conditions by providing users the ability to examine trends and occurrences of certain types of extreme or threshold events at the station-by-station level. It currently provides data and analysis for eight indices that have been defined by the World Meteorological Organization (WMO) Commission for Climatology Expert Team on Climate Change Detection Monitoring and Indices. Additional indices will be added to the NACEM at a later time. The NACEM computes each available index at the station-level and provides corresponding anomalies, data permitting, with respect to the 1961–90 long-term average. An interactive map allows users to select a month, season, or specific year (from 1955 to present) to view a snapshot of values for a specific index across North America. There is also an option to view time series graphics for a station of interest by simply selecting the station.