def daily_mean_t(temperature_min, temperature_max):
    """
    Estimate mean daily temperature from the daily minimum and maximum
    temperatures.

    :param temperature_min: Minimum daily temperature [deg C]
    :param temperature_max: Maximum daily temperature [deg C]
    :return: Mean daily temperature [deg C]
    :rtype: float
    """
    return (temperature_max + temperature_min) / 2.0