Space weather events on the Sun, such as coronal mass ejections and solar flares, can lead to a worldwide disturbance of the geomagnetic field and associated ionospheric and thermospheric disturbances. These events can, and do, impact the performance and reliability of space-based and ground-based operational systems. This paper presents specific examples of the operational impact of space weather events on space surveillance systems. The paper concentrates on the 14 July 2000 event during which the solar-terrestrial environment experienced its largest disturbance in the past 11 years. We report on effects that were detected during the July storm with the Space-Based Visible (SBV) sensor, a visible-band electro-optical system that operates as a contributing sensor for the U. S. Space Surveillance Network. We also discuss the impact of this space weather event on the Global Positioning System (GPS) and on satellite tracking observations by ground-based radars.