WMO Climatological Standard Normals for 1991-2020 (NCEI Accession 0253808)

The World Meteorological Organization (WMO) Climatological Standard Normals are a large suite of data products that provide information about typical climate conditions for thousands of locations across the world. Normals act both as a ruler to compare today’s weather and tomorrow’s forecast, and as a predictor of conditions on a calendar basis. The Normals are calculated for a uniform 30-year period, and consist of monthly averages and statistics of temperature, precipitation, and other climatological variables observed in all member countries. Member countries follow a standard set of methods for performing these calculations, WMO No.1203. The Normals are generated every 10 years in keeping with the needs of our users and the requirements of the WMO. These data allow travelers to pack the right clothes, farmers to plant the best crop varieties, and utilities to plan for seasonal energy usage. Many other important economic decisions that are made beyond the predictive range of standard weather forecasts are either based on or influenced by climate Normals. Finally, they are used most commonly in broadcast meteorology. These valuable data are stored by the World Data Center for Meteorology - Asheville.