Small transport pilot reported a runway excursion due to snow on the runway.

Attributes
ACN	1715190
Time
Date	201912
Local Time Of Day	0001-0600
Place
Locale Reference	ZLC.ARTCC
State Reference	UT
Environment
Flight Conditions	VMC
Aircraft 1
Make Model Name	Small Transport
Flight Phase	Landing
Route In Use	Visual Approach
Flight Plan	IFR
Person 1
Function	Captain Pilot Flying Single Pilot
Qualification	Flight Crew Instrument Flight Crew Multiengine Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 90 Flight Crew Total 5300 Flight Crew Type 2500
Events
Anomaly	Ground Event / Encounter Loss Of Aircraft Control Ground Excursion Runway Inflight Event / Encounter Weather / Turbulence

Narrative:

No WX was available because its a VFR airport; no WX. Cny reported ceiling 9500 calm winds. Bdg reported clear calm winds. I checked area forecast; no significant WX. I checked notams; no notams for U64. On short approach to runway 34; I saw evidence of the runway having been plowed. I saw snow on the runway. I perceived that to be a very small amount of snow due to the plow indications. On touchdown; the snow was much deeper; and pulled aircraft off the runway to the right. After I shutdown the aircraft; I walked back through my tracks; snow was shin deep with drifts that were knee deep. Due to the darkness; I had no depth perception of the depth of the snow.

Original NASA ASRS Text

Title: Small transport pilot reported a runway excursion due to snow on the runway.

Narrative: No WX was available because its a VFR airport; no WX. CNY reported ceiling 9500 calm winds. BDG reported clear calm winds. I checked area forecast; no significant WX. I checked NOTAMs; no NOTAMs for U64. On short approach to Runway 34; I saw evidence of the runway having been plowed. I saw snow on the runway. I perceived that to be a very small amount of snow due to the plow indications. On touchdown; the snow was much deeper; and pulled aircraft off the runway to the right. After I shutdown the aircraft; I walked back through my tracks; snow was shin deep with drifts that were knee deep. Due to the darkness; I had no depth perception of the depth of the snow.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.