Large Transport
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 9
Distraction; Other / Unknown; Situational Awareness
ATC Issue All Types; Conflict Ground Conflict; Critical; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
Air Traffic Control Issued New Clearance; Air Traffic Control Issued Advisory / Alert; Air Traffic Control Separated Traffic; Flight Crew Requested ATC Assistance / Clarification; General Flight Cancelled / Delayed
Airport; Human Factors; Weather
Aircraft Y was cleared for an approach and was cleared to land. Aircraft X called Ground to taxi and was given taxi instructions. This instruction should have resulted in Aircraft X coming out of the Ramp and making a right turn on to the taxiway. Aircraft X instead crossed the taxiway and made a right turn onto the runway. When Aircraft X entered the runway; Aircraft Y immediately stated; 'There's something on the runway;' and I initiated a go around. Aircraft Y went around and conducted another ILS approach to successfully land. Aircraft X exited the runway and continued down the taxiway to Runway 07; where they then departed.Aircraft Y was at 300 ft. at a ½-mile final when the go around was initiated. I asked the pilots of both aircraft to contact the Tower and notified them that I would file a report on the event. I did not say the words 'possible pilot deviation' to Aircraft X; as required to issue a proper brasher warning. I also did not get the pilots' names; phone numbers; and certificate numbers; as I did not know that these items were required until I began filling out the report. I did note on the report that the aircraft were both air carriers; and the information was able to be obtained by referencing the callsigns.I believe the weather was a contributing factor to Aircraft X making an incorrect turn; as it was raining moderately with periodic gusting wind. A ground based radar system or a taller Control Tower would have been incredibly helpful in this circumstance; as the taxiway and runway are pretty much indistinguishable from each other at night. The lights of the two blend together and you cannot tell which is which.
Tower Local Controller reported a taxiing aircraft entered an active runway while an arriving aircraft was on short final and issued a go around to the arriving aircraft.