If it helps, I look up dates for CL here:
Light Sweet Crude Oil

You do NOT want to be trading front month on the Settlement Day!! A Good broker will give you a call if you are still trading it the day before, but hopefully you would notice the volume has gone...

I also use this site to check front month volume levels to decide when to switch each month:
Light Sweet Crude Oil

Brokers usually follow rules and will close out your position days or hours before first notice (long position) or last trading (short position). Last trading day is too late for CL to roll. As it is a commodity with physical supply and demand (unlike financials or gold), the old contract is heavily influenced by the cash market. Positions have to be delivered to the middle of nowhere (Cushing, Oklahoma), and delivery constraints can increase volatility of the old contract. Need to roll at least 3 days prior to last trading.

As a rule of thumb you would roll around the 18th/19th, during the last years it always fell within the period from 15th to 21st of a month. So nex roll date for CL 08-10 will be around June, 18.

LostTrader 

If it helps, I look up dates for CL here: Light Sweet Crude Oil You do NOT want to be trading front month on the Settlement Day!! A Good broker will give you a call if you are still trading it the day before, but hopefully you would notice the volume has gone... I also use this site to check front month volume levels to decide when to switch each month: Light Sweet Crude Oil

Fat Tails 

As a rule of thumb you would roll around the 18th/19th, during the last years it always fell within the period from 15th to 21st of a month. So next roll date for CL 08-10 will be around June, 18.

As a rule of thumb, you would roll when larger volume rolls from the July to the Aug contract. I used to associate that with the equity options expiration but have since learned better.

Do you really believe trading volume will be greater on the Aug contract next Friday?
Or do you actually roll regardless of volume?

I've said before, the third Thursday is usually very near the exact time when volume overtakes from one contract to another, and you switch.

For me, it doesn't have to be an exact science. I don't switch contracts in the middle of the day the moment volume takes over. If I am a day off, the world is not going to end. So, I use the third Thursday rule more or less and just make it consistent.

Mike

Last trading day for the July contract is Tuesday, June 22. So probably volume will shift on Thursday, June 17. Agree with Mike, this is no science. For commodity futures there are no specific rollover dates. Volume cross-over depends on the cash market.

LostTrader 

As a rule of thumb, you would roll when larger volume rolls from the July to the Aug contract. I used to associate that with the equity options expiration but have since learned better. Do you really believe trading volume will be greater on the Aug contract next Friday? Or do you actually roll regardless of volume?

Oh, I agree it isn't science. Just common sense and looking at the data.