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Global Ensemble Forecast System (GEFS) 2.5 Degree

Published by NOAA National Centers for Environmental Information | National Oceanic and Atmospheric Administration, Department of Commerce | Catalog Last Checked: April 12, 2026 at 09:14 PM | Dataset Last Updated: October 01, 2007 at 12:00 AM
The Global Ensemble Forecast System (GEFS) is a weather forecast model made up of 21 separate forecasts, or ensemble members. The National Centers for Environmental Prediction (NCEP) started the GEFS to address the nature of uncertainty in weather observations, which are used to initialize weather forecast models. The proverbial butterfly flapping her wings can have a cascading effect leading to wind gusts thousands of miles away. This extreme example illustrates that tiny, unnoticeable differences between reality and what is actually measured can, over time, lead to noticeable differences between what a weather model forecast predicts and reality itself. The GEFS attempts to quantify the amount of uncertainty in a forecast by generating an ensemble of multiple forecasts, each minutely different, or perturbed, from the original observations. With global coverage, GEFS is produced four times a day with weather forecasts going out to 16 days and a 6 hour temporal resolution. This dataset has 2.5 degree horizontal resolution.

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Earth Science > Atmosphere > Altitude > Geopotential Height Earth Science > Atmosphere > Altitude > Planetary Boundary Layer Height Earth Science > Atmosphere > Altitude > Tropopause Earth Science > Atmosphere > Atmospheric Pressure > Atmospheric Pressure Measurements Earth Science > Atmosphere > Atmospheric Pressure > Pressure Thickness Earth Science > Atmosphere > Atmospheric Pressure > Sea Level Pressure Earth Science > Atmosphere > Atmospheric Pressure > Surface Pressure Earth Science > Atmosphere > Atmospheric Pressure > Albedo

Complete Metadata
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accessLevel public
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describedByType application/octet-steam
description The Global Ensemble Forecast System (GEFS) is a weather forecast model made up of 21 separate forecasts, or ensemble members. The National Centers for Environmental Prediction (NCEP) started the GEFS to address the nature of uncertainty in weather observations, which are used to initialize weather forecast models. The proverbial butterfly flapping her wings can have a cascading effect leading to wind gusts thousands of miles away. This extreme example illustrates that tiny, unnoticeable differences between reality and what is actually measured can, over time, lead to noticeable differences between what a weather model forecast predicts and reality itself. The GEFS attempts to quantify the amount of uncertainty in a forecast by generating an ensemble of multiple forecasts, each minutely different, or perturbed, from the original observations. With global coverage, GEFS is produced four times a day with weather forecasts going out to 16 days and a 6 hour temporal resolution. This dataset has 2.5 degree horizontal resolution.
distribution 
                                            [
  {
    "@type": "dcat:Distribution",
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    "mediaType": "text/html",
    "description": "The information provided on this page seeks to define how the GCMD Keywords are structured, used and accessed. It also provides information on how users can participate in the further development of the keywords.",
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    "description": "Web site providing overview and technical documentation for the GEFS.",
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identifier https://data.noaa.gov/waf/NOAA/NESDIS/ncei/aim/iso/xml/C00692.xml
issued 2007-10-01T00:00:00.000+00:00
keyword 
                                            [
  "Earth Science > Atmosphere > Altitude > Geopotential Height",
  "Earth Science > Atmosphere > Altitude > Planetary Boundary Layer Height",
  "Earth Science > Atmosphere > Altitude > Tropopause",
  "Earth Science > Atmosphere > Atmospheric Pressure > Atmospheric Pressure Measurements",
  "Earth Science > Atmosphere > Atmospheric Pressure > Pressure Thickness",
  "Earth Science > Atmosphere > Atmospheric Pressure > Sea Level Pressure",
  "Earth Science > Atmosphere > Atmospheric Pressure > Surface Pressure",
  "Earth Science > Atmosphere > Atmospheric Pressure > Albedo",
  "Earth Science > Atmosphere > Atmospheric Pressure > Land Cover",
  "Earth Science > Atmosphere > Atmospheric Pressure > Soil Moisture/Water Content",
  "Earth Science > Atmosphere > Atmospheric Pressure > Soil Temperature",
  "Earth Science > Atmosphere > Atmospheric Pressure > Sea Surface Temperature",
  "Earth Science > Atmosphere > Atmospheric Radiation > Albedo",
  "Earth Science > Atmosphere > Atmospheric Radiation > Heat Flux",
  "Earth Science > Atmosphere > Atmospheric Radiation > Incoming Solar Radiation",
  "Earth Science > Atmosphere > Atmospheric Radiation > Longwave Radiation",
  "Earth Science > Atmosphere > Atmospheric Radiation > Outgoing Longwave Radiation",
  "Earth Science > Atmosphere > Atmospheric Radiation > Radiative Flux",
  "Earth Science > Atmosphere > Atmospheric Radiation > Shortwave Radiation",
  "Earth Science > Atmosphere > Atmospheric Radiation > Solar Radiation",
  "Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Air Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Atmospheric Stability",
  "Earth Science > Atmosphere > Atmospheric Temperature > Boundary Layer Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Dew Point Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Maximum/Minimum Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Potential Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature > Skin Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Surface Temperature",
  "Earth Science > Atmosphere > Atmospheric Temperature > Upper Air Temperature",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Dew Point Temperature",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Processes > Evaporation",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Humidity",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Indicators > Total Precipitable Water",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor",
  "Earth Science > Atmosphere > Atmospheric Water Vapor > Water Vapor Profiles",
  "Earth Science > Atmosphere > Atmospheric Winds > Boundary Layer Winds",
  "Earth Science > Atmosphere > Atmospheric Winds > Wind Dynamics > Convection",
  "Earth Science > Atmosphere > Atmospheric Winds > Surface Winds",
  "Earth Science > Atmosphere > Atmospheric Winds > Upper Level Winds",
  "Earth Science > Atmosphere > Atmospheric Winds > Wind Dynamics > Vertical Wind Velocity/Speed",
  "Earth Science > Atmosphere > Atmospheric Winds > Wind Dynamics > Vorticity",
  "Earth Science > Atmosphere > Atmospheric Winds > Wind Profiles",
  "Earth Science > Atmosphere > Atmospheric Winds > Wind Dynamics > Wind Shear",
  "Earth Science > Atmosphere > Precipitation > Liquid Precipitation > Rain > Freezing Rain",
  "Earth Science > Atmosphere > Precipitation > Precipitation Amount",
  "Earth Science > Atmosphere > Precipitation > Precipitation Rate",
  "Earth Science > Atmosphere > Precipitation > Liquid Precipitation > Rain",
  "Earth Science > Atmosphere > Precipitation > Solid Precipitation > Ice Pellets > Sleet",
  "Earth Science > Atmosphere > Precipitation > Solid Precipitation > Snow",
  "Earth Science > Atmosphere > Air Quality > Tropospheric Ozone",
  "Earth Science > Terrestrial Hydrosphere > Snow/Ice > Albedo",
  "Earth Science > Terrestrial Hydrosphere > Snow/Ice > Snow Cover",
  "Earth Science > Terrestrial Hydrosphere > Snow/Ice > Snow Depth",
  "Earth Science > Terrestrial Hydrosphere > Snow/Ice > Snow Water Equivalent",
  "Earth Science > Oceans > Sea Ice > Sea Ice Concentration",
  "Earth Science > Land Surface > Surface Radiative Properties > Albedo",
  "Earth Science > Land Surface > Land Use/Land Cover > Land Use/Land Cover Classification > Vegetation Index",
  "Earth Science > Land Surface > Soils > Soil Moisture/Water Content",
  "Earth Science > Land Surface > Soils > Soil Temperature",
  "Earth Science > Oceans > Ocean Temperature > Sea Surface Temperature",
  "Geographic Region > Global",
  "Vertical Location > Boundary Layer",
  "Vertical Location > Land Surface",
  "Vertical Location > Sea Surface",
  "Vertical Location > Troposphere",
  "Vertical Location > Stratosphere",
  "NOMADS > The NOAA Operational Model Archive and Distribution System",
  "250 km - < 500 km or approximately 2.5 degrees - < 5.0 degrees",
  "DOC/NOAA/NESDIS/NCDC > National Climatic Data Center, NESDIS, NOAA, U.S. Department of Commerce",
  "DOC/NOAA/NESDIS/NCEI > National Centers for Environmental Information, NESDIS, NOAA, U.S. Department of Commerce"
]
landingPage https://www.emc.ncep.noaa.gov/emc/pages/numerical_forecast_systems/gefs.php
language 
                                            []
license https://creativecommons.org/publicdomain/zero/1.0/
modified 2007-10-01T00:00:00.000+00:00
publisher 
                                            {
  "name": "NOAA National Centers for Environmental Information",
  "@type": "org:Organization"
}
spatial 180.0,-90.0,-180.0,90.0
temporal 2008-01-01T00:00:00+00:00/2020-09-23T00:00:00+00:00
title Global Ensemble Forecast System (GEFS) 2.5 Degree

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