On a clear day in June the terrace has sun 07:00–13:40, about 6.5 hours in total. In short: sun at lunch.
The story of Cafe Söderberg
Café Söderberg opened in 1994 beside Jakob's Church in Kungsträdgården, across from the Royal Opera. It is named after the writer Hjalmar Söderberg.
A water kiosk once stood on this spot, open from 1850 until 1933. In Söderberg's 1905 novel Doctor Glas, this is where the title character poisons Pastor Gregorius. A literary plaque telling the story has stood here since 1992, one of the first the City of Stockholm put up.
The café is built in a turn-of-the-century style and looks out towards Strömmen. It is open all year, and in summer the terrace seats more than 150.
Sources: Wikipedia: Café Söderberg · Café Söderberg: Om oss
How Stoligt works it out
Every ten minutes we draw a line from each terrace toward the sun and check whether a building or hill is tall enough to block it. Building heights come from OpenStreetMap and ground heights from Lantmäteriet, the Swedish mapping agency. The times assume a clear day, so clouds are not included here. They are on the live map, which shows today's weather.
Trees, parasols and awnings are not in the model, and we don't know exactly where on the pavement the tables stand. Treat the times as an educated guess, often accurate to within ten minutes.