Most everyone who has lived in California for a while has heard of earthquake weather. I've lived in Southern California all my life and am very much aware of and in tune with the phenomena. Basically, when the weather makes dramatic, short-term changes from cool to hot to cool or hot to cool to hot, we can expect an earthquake. It's not science, I know, but the two have gone hand-in-hand often enough that it has become predictable.

Sunday, Monday, and Tuesday were uncharacteristically hot for April in Southern California. We had a mini heatwave that increased our temperature from the norm in the 70s to upwards of 90 degrees. When the heatwave ended, we went from 93 in the daytime to a nighttime low of 54! Now that's a dramatic fluctuation in the temperature and the hallmark of "earthquake weather." Whether it's intuition or experience, I can't say, but through the years, I've become pretty doggone good at recognizing the weather patterns that portend a temblor and am seldom off when I predict a quake. In fact, family and friends have been known to ask me whether or not we're having "earthquake weather."

It was not a major surprise then, for me at least, that we had two quakes yesterday.

Both of the quakes were centered in Yorba Linda, hometown of Richard M. Nixon, about 2 miles from our business in Fullerton which is where I was when the first quake hit. From someone who has experienced several major and memorable California quakes, including

• 6.6 Sylmar (San Fernando) Quake on 2-9-71 -- This one cracked the foundation of our home, some 30 miles away from the epicenter!
• 5.9 Whittier Narrows Quake on 10-1-87
• 5.0 Pasadena Quake on 12-3-88
• 5.4 Upland Quake on 2-28-90
• 6.1 Joshua Tree Quake on 4-22-92
• 7.3 Landers Quake at 4:57 AM on 6-28-92 -- This was the most frightening earthquake I have ever experienced, mostly because it was followed by several very strong aftershocks; it caused so much shaking that the water from our swimming pool overflowed from the deck into our living room! Some amazing photos, including a few that show the crack (total length is about 53 miles!) in the earth's surface that resulted from this quake, are available here.
  
• 6.4 Big Bear Quake at 8:05 AM on 6-28-92 -- Technically, this one was an aftershock from the Landers Quake -- the biggest of the aftershocks the followed it -- but it occurred on a completely different fault than Landers
• 5.7 Mojave Quake on 7-11-92
• 6.7 Northridge Quake at 4:30 AM on 1-17-94 -- Although not as strong on the seismograph as the Landers quake, this one shook longer and harder. Because the epicenter was directly beneath a heavily populated city, this quake collapsed several sections of a major freeway, toppled the crown of a landmark artdeco skyscraper in Hollywood, and triggered the collapse of several buildings. You can see some amazing photos of the damage here.
• 5.4 Ridgecrest Quake on 8-17-95 -- Not big as far as earthquakes go, but this one is rememberable for the more than 2,500 aftershocks that followed, some of which measured in at 6.0!
• 7.1 Hector Mine Quake on 10-16-99 -- This quake happened so far out in the desert that although it was really strong, it didn't cause much damage beyond a surface split and lots of rattled nerves.

I can honestly say that yesterday's temblors weren't very impressive. Both were short in terms of time (barely 2-3 seconds long) and shaking. Actually, there wasn't any shake to these quakes -- they were snapping motions. The aftershocks and microquakes continue, with the last one happening about an hour ago (it is currently 4:43 AM PDT). It will be interesting to see what, if anything, develops over the next few days. We live on the San Andreas Fault, one of the most active fault lines in the state. Since it's been a while since we had a big one, I suppose now would be a really good time to give the old earthquake survival supplies box a quick once over.