Here is the BTC dominance graph.
Currently its at 69.31%.
Todays highest dominance was 69.78%
The highest on 6th Dec 2017 was 69.99% and from there it dumped for almost 50%.
But this time,case is different.
BTC seems to be breaking the level of 70%. If we break that level and if we close above 70%,then we will be moving towards 75% dominance which means there will be more blood on the streets.
Unless BTC dominance comes down,its better to stay out of alts.
Stay safe.
Cheers!!!