Medium Transport; Low Wing; 2 Turbojet Eng
Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine; Flight Crew Instrument
Flight Crew Last 90 Days 70; Flight Crew Total 7800; Flight Crew Type 300
Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
General None Reported / Taken
Weather; Human Factors
We were cleared for taxi to Runway 1. We exited the ramp at Taxiway D and proceeded southbound on Taxiway A. In order to maximize available runway; we followed the second (southernmost) curved taxiway center line onto Taxiway A1; toward the active runway. We observed the enhanced taxiway center line markings; however as the Taxiway A transitioned to Taxiway A1 the hold-short line was completely obscured by packed snow.We stopped the aircraft approximately 60 feet past what we estimate to be the location of the hold-short line and immediately notified the Tower of our error. We were instructed to perform a 180 back to Taxiway A. The incursion did not present any immediate conflict to other aircraft. Another aircraft was simultaneously taxiing on the active runway for the north de-icing pad. The nearest arriving aircraft was greater than 10 miles away and had not yet been cleared to land.Upon further analysis of the error; we (the crew) determined that the short taxi certainly contributed to the confusion. The Holding Position sign for RWY 1-19 is situated on the northern edge of Taxiway A1 and angled to the northeast; in a manner that makes it very easy to miss when entering Taxiway A from Taxiway D. By the time the aircraft is established on Taxiway A; that sign is already abeam the aircraft. From the perspective of the pilot flying from the left seat; that sign is not visible in this situation. But the most significant factor in our misstep today was the nearly complete obscuration of the hold short line at the intersection of taxiways A and A1.
Pilot reported a runway incursion at JAC airport and cited snow obscuring the hold short line and the position of the Holding Position sign contributed to the event.