A heat flux temperature sensor probe includes a first mineral-insulated cable portion and a second mineral-insulated cable portion. The first mineral-insulated cable portion has a first metallic sheath, a first plurality of thermocouple conductors extending therein, and an inorganic insulative material insulating the first plurality of thermocouple conductors from one another and from the first metallic sheath. The second mineral-insulated cable portion has a second metallic sheath, a second plurality of thermocouple conductors extending therein, and an inorganic insulative material insulating the second plurality of thermocouple conductors from one another and from the second metallic sheath. A first thermocouple is formed between at least one of the first plurality of thermocouple conductors and one of the second plurality of thermocouple conductors proximate a first end of the second mineral-insulated cable portion. A second thermocouple is formed between at least two of the second plurality of thermocouple conductors proximate a second end of the second mineral-insulated cable. A sheath is operably coupled to and connects the first and second mineral insulated cable portions, a portion of an interior of the sheath is filled with a non-conductive material.