internal cooking temperature for medium prime rib roast
30 minutes before the end of the cooking time remove the prime rib roast from the oven and check the internal temperature. For the roast to be rare the internal temperature should be 120Â°F to 125Â°F but remove from the oven when it is 115Â°F to 120Â°F and allow to stand for 20 minutes.0 minutes before the end of the cooking time remove the prime rib roast from the oven and check the internal temperature. For the roast to be rare the internal temperature should be 120Â°F to 125Â°F but remove from the oven when it is 115Â°F to 120Â°F and allow to stand for 20 minutes.