Space weather refers to the Sun's influence on Earth and its surrounding space and is one of the pillars of establishing and maintaining timely and actionable space situational awareness. This is due to different types of solar storms affecting the atmosphere and satellite orbits, especially in low earth orbits. The report aims to offer the reader a general understanding of the effects of space weather, and how they affect space domain awareness. It is of particular interest as the Swedish Armed Forces plan to own and operate their own satellites by 2030. By using open literature, data and models for space weather, space weather is described at a general level, and concepts and phenomena are visualized to exemplify how space weather affects the Swedish Armed Forces' operations. We aim to give an overview of all affected systems relevant for space domain awareness and the effect space weather has on them. Solar flares and coronal mass ejections affect several systems of interest, for example shortwave radio, satellite navigation, aviation, satellites, power grids, and the monitoring and surveying of space objects. Forecasts of space weather are difficult to make and currently relatively uncertain due to limitations in the models, number of observations, computational resources and that the physics not being fully understood. We review the most used methods for different types of storms. We also study the limitations of forecasts and review and evaluate the most used methods. The Swedish Armed Forces' current forecasts and future needs are reviewed, and we present recommendations for what a space weather service might look like in the future.