A laser ceilometer, an acoustic sounder, and a microwave radiometer were used to estimate cloud thickness and the adiabatic and integrated liquid water content of shallow stratocumulus clouds continuously for three days using two-minute averages. Although the observed liquid water path was close to the theoretical adiabatic value for most of the three days, there was one four-hour period when the liquid water content dropped to about 50% of the adiabatic value. Hourly-averaged values for a 19-day period of intensive observations show that the cloud water content was generally close to the adiabatic value. Occassionally there were clouds greater than 300 m in depth in which the water content was clearly less than adiabatic. ¿ American Geophysical Union 1990