Novel applications for plasma actuators necessitate performance predictions that are reliable at a range of environmental conditions. An experimental setup is used to determine how Single Dielectric Barrier Discharge (SDBD) plasma actuators perform under variable ambient pressure. Measurements of plasma initiation voltage and static thrust were compared to similar data from literature. Recurring trends in the experimental thrust were evaluated against simulations from the Space-Time Lumped Element Model, which was designed strictly for atmospheric pressure. Parameters in the model affected by ambient pressure (capacitance, resistance, and Debye length of the air) were then systematically adjusted to determine their effects on the plasma-produced body force. Even with an empirical approximation of threshold voltage, the model did not predict a body force that changed with pressure in a similar manner to experiment. Filament formation, not physically represented in the model, was very prevalent at pressures above atmospheric and may be responsible for the complicated trends in data.