Bubba turned on heater 3A yesterday to help deal with the cold conditions. You can see in the plot that the heater is cycling, probably on a protective temperature switch.

Nutsinee reported some misbehavior in the LVEA 10-30 Hz seismic activity.

I'm not sure there is any correlation between these two events but someone might look at this. The heater is likely ~25kw so there is some significant EMI from the contactor opening and closing.