The frontal passage of Thursday and Friday brought an interesting conclusion to a warm, wet, and windy week in the San Joaquin Valley.
The first wave of heavy rainfall from Thursday's storm moved into Turlock shortly after noon, and was accompanied by quite a bit of thunder and lightning. In a one-hour time period, .45 of an inch of rain fell at my station. Two more bouts of heavy rain, lightning, and thunder swept through the area during the evening of the 21st, boosting the day's rainfall total to .80 of an inch. Thunderstorms continued to fire up over the Sierra Nevada foothills well into the morning of the 22nd, providing a spectacular display of lightning to the east all night long.
After moderate rain showers passed through the area after sunrise on the 22nd, skies cleared. The sun was out long enough to allow the temperature to rise into the mid-60s by noon. However, the dew point was near 60F, and a brisk wind had picked up out of the south, so I had a feeling it was a matter of time before the atmosphere began to "pop". Sure enough, cumulus towers off to my southeast began shooting rapidly towards the tropopause at 1300, while an organized line of heavy showers was showing up on radar about 40 mi to my NW. Unfortunately, my location does not exactly provide a good view of the horizon in any direction, so I got in my car at 1330 and headed into rural areas of eastern Stanislaus County where I would have a better view.
Once I had a clear view to the east and southeast, I noticed some suspicious lowerings along the base of what had now become a cumulonimbus. I thought about pursuing this cloud for a moment, but decided to stick to my main focus of watching the line of Cb approaching from the northwest. It appeared that some Cu was beginning to build up southwest of the line, and that the Cu was headed towards Turlock. I decided to head back home shortly before 1400, a decision I would later learn was unwise.
The line of Cu did look threatening as it finally arrived in Turlock at 1600, but resulted in little more than a very light sprinkle a gradual wind shift to the west as it moved overhead. The Cb to the southeast I mentioned earlier turned out to become quite potent. At 1400, a tornado touched down at a golf course three miles northeast of Merced. Had I stuck to my guns and headed southeast, I would have arrived in Merced around 1400, possibly just in time to witness the tornado touch down. But had I actually headed towards Merced, I probably would have jinxed the tornado. :-)
From Saturday the 16th to Friday the 22nd, I recorded 1.92 inches of rain. The rainfall total for the season is already an impressive 3.75 inches, a far cry from the .03 of an inch season total at the same time last year.