A process fluid temperature calculation system comprising: a first temperature sensor disposed to measure an external temperature of a process fluid conduit; a stem portion having a known thermal impedance; a housing attached to the stem portion, the housing comprising: a second temperature sensor spaced from the first temperature sensor by the stem portion, the second temperature sensor being coupled to a terminal block within the housing and being configured to provide a terminal temperature measurement; a measurement circuitry coupled to the first and second temperature sensors (152, 162); a memory configured to store a thermal impedance parameter of the stem portion and a thermal impedance parameter of pipe material; and a microprocessor coupled to the measurement circuitry, and configured to receive temperature information from the measurement circuitry and to calculate a process fluid temperature output using a heat flux calculation, the process fluid temperature being calculated based on the received temperature information and the thermal impedance parameters of the stem portion and pipe material stored in the memory, wherein the microprocessor is configured to dynamically compensate the temperature output based on a rate of change of temperature measured by the first temperature sensor in comparison to a rate of change of temperature measured by the second temperature sensor, by adjusting the thermal impedance parameter of the stem portion stored in the memory. a first temperature sensor disposed to measure an external temperature of a process fluid conduit; a stem portion having a known thermal impedance; a housing attached to the stem portion, the housing comprising: a second temperature sensor spaced from the first temperature sensor by the stem portion, the second temperature sensor being coupled to a terminal block within the housing and being configured to provide a terminal temperature measurement; a measurement circuitry coupled to the first and second temperature sensors (152, 162); a memory configured to store a thermal impedance parameter of the stem portion and a thermal impedance parameter of pipe material; and a microprocessor coupled to the measurement circuitry, and configured to receive temperature information from the measurement circuitry and to calculate a process fluid temperature output using a heat flux calculation, the process fluid temperature being calculated based on the received temperature information and the thermal impedance parameters of the stem portion and pipe material stored in the memory, wherein the microprocessor is configured to dynamically compensate the temperature output based on a rate of change of temperature measured by the first temperature sensor in comparison to a rate of change of temperature measured by the second temperature sensor, by adjusting the thermal impedance parameter of the stem portion stored in the memory. a second temperature sensor spaced from the first temperature sensor by the stem portion, the second temperature sensor being coupled to a terminal block within the housing and being configured to provide a terminal temperature measurement; a measurement circuitry coupled to the first and second temperature sensors (152, 162); a memory configured to store a thermal impedance parameter of the stem portion and a thermal impedance parameter of pipe material; and a microprocessor coupled to the measurement circuitry, and configured to receive temperature information from the measurement circuitry and to calculate a process fluid temperature output using a heat flux calculation, the process fluid temperature being calculated based on the received temperature information and the thermal impedance parameters of the stem portion and pipe material stored in the memory, wherein the microprocessor is configured to dynamically compensate the temperature output based on a rate of change of temperature measured by the first temperature sensor in comparison to a rate of change of temperature measured by the second temperature sensor, by adjusting the thermal impedance parameter of the stem portion stored in the memory.