Here is a useful service if you want to be notified about any geomagnetic storms:
https://mailman.rice.edu/mailman/listinfo/spacalrt
This mailing list only sends you a brief message whenever there is any GM storm going on.
It is very convenient.
Danny
LunaticTrader Blog 
Danny, based on the Boyle Index (as you know), this alert is highly reliable and I have found it to be more predictive than many other indices and services.