Abstract: A power line ampacity system called LINEAMPS is invented by object oriented modeling and expert rules of the power line environment. Ampacity is estimated by the solution of conductor temperature differential equations using synthetic generation of meteorological data adjusted to national weather service forecast. The line ampacity system provides hourly values of present and future power line ampacity up to seven days in advance. The program has steady state, dynamic and transient ampacity models which can accurately respond to any weather condition or line currents. The system does not require real time meteorological data, conductor temperature measurements or new hardware on power lines. In the absence of real time meteorological data the system generates power line ampacity from the stored weather patterns of the region located in the weather station objects. LINEAMPS is applicable to all overhead power lines and is easily implemented in all geographic regions.