I appreciate very much your sense of observation Aaron (which maybe correlated to your gift for illustration):
"I have more seizures before a thunderstorm."
"I think that the correlation is with the barometric pressure."
You could also add another possibility: the influence of electric fields.
A psychological stress or an excitation could also be other possible causes.
How could we test these hypothesis?
Probably no easy way!
Controlling the air pressure in your house is for sure very difficult.
However, you could easier check if a stay at the mountain has an impact.
From the air pressure vs altitude table (1), you can see that an altitude of 2000 m would be relevant.
(a decrease by 20 kPa already means bad weather)
So this looks a feasible approach.
Controlling the electric fields is a bit easier.
You "simply" need to shield the room you live in.
As nearly static fields are involved, the shielding can be very simple: conductors around your room, correctly grounded.
They don't need to be very close to each other.
Long strips of aluminium foils could be excellent.
Maybe there are also conducting paints.
Note that I think electric fields a less probable reason: the human body is nearly equipotential because of its excellent conductivity.
Psychological stress or excitation effects might be much more difficult to test.
(1)
http://www.engineeringtoolbox.com/air-altitude-pressure-d_462.html