Nobody knows what the price will be in 1 months, 6 months, etc.
There is always some degree of risk. Don't risk anymore then you can afford to lose.
The best time to start Ethereum mining was in January.
Certainity is always there,but even if the price fall and I keep on mining,I dont mind getting the ROI some time later.At least I will be keeping up generating ethers,No?
If the price is below the cost of mining, it is better to buy the coins instead of mining the coin directly.