The flare this morning occurred as follows according to SEC:
Flare # Begin MAX END Size
7000 + 1623 1645 1704 GO8 5 XRA 1-8A X5.3 8.2E-01 9591
This is the largest flare since April, so batten down the hatches. Seismicity
could skyrocket in a couple of days, at least according to some theorists. A
geomagnetic storm began shortly after the flare. This is known as SFE (solar
flare effects). The particle stream should arrive in the next 2-5 days.
Historically, large (M>=7) and great (M>=8) earthquakes occur 4-5 days
after strong flares in regions near the geomagnetic poles and along the
geomagnetic equator. This includes places like northern Canada, Alaska,
Vancouver Island, New Zealand, etc.
The timing of the flare at 16:23 UT means that areas which were directly under
the sun at the time (or on the opposite side of the world) sub-solar or anti-solar
feel the strongest effects. These areas include eastern U.S. and Canada
and the Caribbean and the coastline of So. America which were sub-solar
and Taiwan, Moluccas, Philippines, Honshu, which were anti-solar. A lot
of these areas have high rates of seismicity, so be prepared for a few interesting
days.
Of course, Don also mentioned the possibility in his post that a geomagnetic
storm could increase the magnitude of an earthquake west of L.A.
All this is speculative, of course. All that can be done is to sit back
and wait for whatever happens to happen. This is not a great flare, as
flares go, but since it has been 4 months since the last such, it's impact
may be more than it's size anticipates.

• Solar flares for Aug 25, 2001