Nighttime thermospheric winds and temperatures have been measured over Fritz Peak Observatory, Colorado (39.9¿N, 105.5 ¿W), with a high-resolution Fabry-Perot spectrometer during the March 2, 1983, geomagnetic storm. The winds and temperatures are obtained from the Doppler shifts and line profiles of the [O i> 15,867 K 9630 nm) line emission. The planetary geomagnetic index, Kp, increased abruptly from 4 to 7 during the beginning of the measuring period near 0000 UT on March 2 and remained at nearly that level throughout the night. During the early evening hours near 1900 LT (0200 UT) the zonal winds measured in both the east and west directions fromFritz Peak Observatory were westward at a speed of about 100 m s-1. The westward winds increased in magnitude during the next 2 hours, with the wind speed east of the station reaching 400 m s-1 and the winds to the west of the station reaching 300 m s-1. The westward winds remained at roughly these speeds until about local midnight (0700 UT), when they gradually decreased to about 50 m s-1 in the east, and the winds to the west of the station shifted to eastward at about 50 m s-1. The meridional winds measured in the early evening hours both to the north and south of the station were poleward at speeds ranging between 50 and 10 m s-1. Near local midnight the wind measured north of the station gradually shifted to equatorward, reaching a maximum speed of about 300 m s-1 near 0200 LT (0900 UT) and then decreasing to about 100 m s-1 near dawn. The wind measured south of the station remained poleward throughout the night at speeds ranging between 25 and 100 m s-1. The neutral gas temperature over Fritz Peak Observatory increased throughout the night from about 1300¿ to 1600 ¿K. Calculations made with the National Center for Atmospheric Research thermospheric general circulation model suggest that the observed winds over Fritz Peak Observatory (L≂3) are under the influence of an expanded magnetospheric convection pattern during the storm. Enhanced magnetospheric convection at mid-latitudes characteristically produces westward winds during the early evening hours and a strong equatorward surge in the postmidnight winds.