how accurate are the predictions for coronal mass ejections-(location, timing and magnitude)? I suppose this applies to all solar events.

I know centuries ago they knew the quantity of these things fluxuated in  solar cycles. Apart from that I know there has been advancement in solar weather forecasting but how accurate is it? Could, say ESA, have enough foreknowledge to launch a satellite or have one poised in solar orbit to 'go fishing' to investigate the emissions in someway? ?composition of particles- for example?
Old question; I hope you’re still active here…
Basically, we CAN’T predict coronal mass ejections in advance. See http://solar.physics.montana.edu/press/ssu_index.html
Other solar events, such as the number of sunspots, are somewhat predictable—not precisely, but at least have an idea about them. For example, sunspots follow a cycle of approximately 11 years. However, we don’t know before a cycle if it will be strong or not—our models are still too imprecise, though, like you wrote, there has been some advancement, but not much.