Recently, researchers studying satellite images of the sun have paid special attention to great, S-shaped twists of plasma called sigmoids that they now believe are an early stage of CME formation. Find a sigmoid, and within a few days you'll probably see an explosion. Since it takes an additional four days for the solar tsunami to reach Earth, you can double today's early-warning time. That time can be well used. Satellite operators who know a cme storm front is coming can briefly shut their systems off to prevent short-circuiting.
Astronauts planning a space walk can stay indoors until the danger passes.
Now, it seems, humanity may have a better chance of dodging the bullet.