We also had a pretty nasty earthquake recently.
Earthquakes usually occur pretty deep within the earth.
For example, the depth of the latest earthquake in Los Angeles was about 12 miles. The weight of any added rainfall would be small compared to the weight of 12 miles of earth. However, some people do believe in a connection between weather and earthquakes. The idea is that earthquakes are more likely to occur during hot weather. A scientist, Jerome Namias, from the Scripps Institution of Oceanography, published a paper in 1989 suggesting that earthquakes do occur more often in hot weather.