sääkarttoja

Sääkarttoja, the Finnish term for weather maps, are meteorological charts that visualize current and forecast weather conditions for a defined region and time. They combine data from weather stations, satellites, radar, and other observation networks and present it in a spatial format that allows forecasters and decision makers to interpret atmospheric patterns. Common elements include isobars (lines of equal pressure), isotherms (lines of equal temperature), precipitation areas, wind barbs indicating speed and direction, cloud cover, and fronts.

There are several key types of sääkarttoja. Surface weather maps (pinta sääkartat) show conditions near the Earth's surface, including temperature, humidity, pressure, wind, and precipitation. Upper-air charts (yläilmakehän kartat) depict atmospheric conditions higher in the atmosphere, such as geopotential height and temperature in different layers. Satellite-based maps illustrate cloud patterns and infrared or visible temperatures, while radar maps display precipitation intensity and movement. Forecast maps derive from numerical weather prediction models and project conditions at future times, often at multiple forecast horizons.

Production and use involve collecting observations from a wide network and processing them into interpretable formats. Meteorologists analyze these maps to identify weather systems, fronts, and impending weather changes, supporting short-term nowcasting and longer-range forecasts. Sääkarttoja are produced by national meteorological institutes, such as Finland’s Ilmatieteen laitos, and by international centers, and are widely accessible online and through apps and other media for aviation, maritime, agriculture, and public safety uses.