Uppsala, where it's located

The climate of Uppsala is Baltic, that is, moderately continental, with cold winters, during which the average temperature is a few degrees below freezing, and mild to pleasantly warm summers.
The city is located in southern Sweden, 25 km (15 mi) north-west of Stockholm.
The average temperature of the coldest month (February) is of -3.1 °C (27 °F), that of the warmest month (July) is of 17.6 °C (64 °F). However, during polar cold spells, the temperature can drop to -25 °C (-13 °F) or below, while in summer, it can reach 28/30 °C (82/86 °F), although rarely. Here are the average temperatures.
Uppsala - Average temperatures
Min (°C)-6-6-3059121273-1-4
Max (°C)0041016202321161041
Min (°F)212127324148545445373025
Max (°F)323239506168737061503934

Precipitation amounts to 575 millimeters (22.6 inches) per year: so, it is at an intermediate level. It ranges from 30 mm (1.2 in) in the driest months (February, April) to 75 mm (3 in) in the wettest (August). Here is the average precipitation.
Uppsala - Average precipitation

On average, there are around 1,775 sunshine hours per year. Here are the average sunshine hours per day.
Uppsala - Sunshine


Best Time

The best time to visit Uppsala is the summer, from June to August, since it is the mildest season. However, you must take into account some rainy days and a bit of cold at night.