The Department of Infrastructure says the Mountain Road is unlikely to open this weekend.
On Facebook, it says more freezing weather looks set to bring further wintry showers along the route.
It closed the length of the road earlier today after heavy snow overnight.
The DOI says it'll continue monitoring conditions and will reopen it sooner if it's safe to do so - but adds it's likely to open again on Monday, February 16.
Fuel price hit may last into winter, says government
Further temporary speed limits on TT course
Western homes to be without water tomorrow
Co-Op ordered to hand over evidence in blind worker's tribunal
Who'll be getting meningitis vaccines?
New atlas shows dramatic fall in Island birth rate
Autocar lavishes praise on Island's roads
Super Unleaded hits almost 165p a litre