This week's Premier League games at Aberdeen, St Johnstone, Kilmarnock and Hamilton have both been postponed over public safety fears.
Tuesday's scheduled clash between Aberdeen and Falkirk and Wednesday's Hamilton-St Mirren game have been called off due to adverse weather conditions.
An SPL spokesman said: "The playing surfaces were in order but in both cases the police made the decision on the grounds of public safety.
"We are touch with our clubs about the other games and will keep everyone updated with any developments.''
St Johnstone's clash with Hibernian, which was due to take place at McDairmid Park in Perth on Wednesday, has also been postponed by the Scottish Premier League for the same reasons.
Celtic's bid to enter the new year by narrowing the gap to leaders Rangers was hit by the postponement of their clash at Kilmarnock.
Once again it was ruled unsafe for spectators to travel to the game, which was due to be staged at Rugby Park on Wednesday.
Celtic chief executive Peter Lawwell has blamed Kilmarnock for their clash being postponed. Celtic believe the Ayrshire club neglected its responsibility to "ensure the stadium locality is safe''.
Lawwell told Celtic's official website: "Clearly, we are extremely disappointed that the match has been postponed. We have been told that the pitch is perfectly playable, but we have also been informed that the match cannot proceed due to the stadium footprint (area surrounding the stadium) not being cleared.
"Naturally this is very frustrating for the club and its supporters. As is always the case, it is the responsibility of home clubs to ensure that their own footprint or locality is safe and obviously in this case, this has not been achieved.''
It left Rangers' clash with third-placed Dundee United and Hearts' match with Motherwell as the only fixtures set to take place this week.
The Tynecastle clash will be subject to a 2pm pitch inspection on Wednesday to assess supporter safety and accessibility.
The pitch was playable this afternoon but Hearts staff are clearing ice and snow and laying salt around the stadium. The club are expecting a delivery of salt supplies on Wednesday morning.
A club spokesperson said: "We are hopeful that the game will proceed as planned. We are continuing to sell tickets for the game and are expecting a large crowd at Tynecastle.
"We are therefore doing everything we can to clear the ice and snow-covered areas around the stadium. Naturally we will also be monitoring the weather forecast between now and then.
"We are also very conscious of the distances that supporters of both Hearts and Motherwell have to make in order to get to the game and, as such, we fully intend to release a statement as soon as possible after the 2pm inspection.''