A study was made to examine the near-surface water balance of a dry prairie site in west-central Florida. The water balance, which was defined on a unit area basis and for a depth of 5.5 meters, was described for the period June 1991 to October 1992. Precipitation during the 498 days of field measurements was 2,245 millimeters. Evapotranspiration, the second largest component, was 1,419 millimeters. Water yield was 808 millimeters and the change in soil water storage was 19 millimeters. Computed vertical water flux was less than 4 percent of evapotranspiration because of the small hydraulic conductivity of a clay layer that began at a depth of 5.5 meters.