30-day long-range forecast
Choose a city for a 30-day forecast. Days 1-14 come from global weather models; days 15-30 are synthesised from SMHI’s climate normals 1991-2020 — season-typical values with weekly variation, NOT an exact forecast that far ahead.
Major cities
About synthesised forecasts
Climate normals 1991-2020 from SMHI
Real weather forecasts have a horizon of ~14 days — beyond that the uncertainty becomes larger than the variation. For days 15-30 we show season-typical values: the month’s average Tmax and Tmin from SMHI’s climate normals 1991-2020, adjusted for the location’s latitude and with a mild weekly variation. Good for planning ("roughly how warm does it get in Stockholm in the third week of July") — NOT an exact forecast for a specific day.