Learn about temperature statistics
Short guides on how temperature is measured, averaged and compared.
How temperature is measured
Height, shade, sensors and reading times: how SMHI measures air temperature, and which of its series Temperaturkollen uses.
Daily mean temperature
How SMHI calculates a daily mean, which day it belongs to, and how Temperaturkollen turns daily means into weekly, monthly and annual values.
Why climate normals matter
A temperature on its own says little. What a climate normal is, what it is used for, and why it is not the same as "usual".
The 1991–2020 normal
How SMHI's official 1991–2020 normals are calculated, how much warmer they are than 1961–1990, and how Temperaturkollen derives a daily reference.
Temperature records
Sweden's highest and lowest measured temperatures, why records need care, and when Temperaturkollen uses the word "record".
Observation vs forecast
Temperaturkollen shows measurements only. How an observation differs from a model value and a forecast, and how the "right now" value is chosen.
Why stations differ
Valleys, coasts, towns and clear nights: why two nearby stations can differ noticeably, and how Temperaturkollen picks a station for a place.
How comparisons work
The exact rules behind the comparison chart: calendar dates, leap days, cut-off at yesterday, coverage and the three key figures.