After driving 300 miles to see storms on Monday, I was treated to some storms much closer to home Tuesday.
Showers and thunderstorms took much longer to get going over the valley Tuesday than they did Monday. Cb's had built up seemingly over the entire Coast Range and Sierra Nevada by noon, yet only SCT fair-wx Cu built up over the valley. But at 1600, a cell developed in the valley right over Modesto. This cell drifted SE over Turlock - giving us heavy rain and 1/4 inch hail from 1637 to 1645 before dissipating. Over the next two hours, more Cb's went up over the valley - most notably in San Joaquin and northern Stanislaus County. I hadn't planned on doing any chasing - in fact, I was looking forward to a nice evening relaxing at home. That was until this report came over the wire....
ZCZC SFOSPSSAC TTAA00 KSAC 150149 CAZ019-150230- SPECIAL WEATHER STATEMENT NATIONAL WEATHER SERVICE SACRAMENTO CA 640 PM PDT TUE APR 14 1998 ...FUNNEL CLOUDS OBSERVED ACROSS NORTHERN SAN JOAQUIN VALLEY... SEVERAL REPORTS OF FUNNEL CLOUDS WERE RECEIVED AT AROUND 630 PM IN THE ESCALON AND OAKDALE AREAS OF EASTERN SAN JOAQUIN AND STANISLAUS COUNTY. LAW ENFORCEMENT PERSONNEL REPORTED NO TOUCHDOWN IN THESE AREAS. DOPPLER WEATHER RADAR IN SACRAMENTO CONTINUES TO SHOW SHOWER AND THUNDERSTORM ACTIVITY IN THESE AREAS BUT A WEAKENING TREND WAS BEING NOTED. PERSONS IN EASTERN SAN JOAQUIN AND EASTERN STANISLAUS COUNTY WILL WANT TO STAY ALERT FOR THE POTENTIAL OF ADDITIONAL FUNNEL CLOUDS BUT REALIZE THAT THEY ONLY RARELY TOUCH THE GROUND. IF ONE IS SPOTTED IN YOUR LOCATION AND APPROACHES THE GROUND...MOVE TO A PLACE OF SAFETY. THE SHOWER AND THUNDERSTORM ACTIVITY...WHICH MAY PRODUCE PEA TO MARBLE SIZE HAIL...SHOULD DECREASE BY EARLY THIS EVENING. SWANBERG
Needless to say, I was out the door and gone within two minutes.
As I was heading north on Route J-14 out of Turlock, I could see the Escalon/Oakdale activity was raining itself out. However, new cells were regenerating to the SW, W, and NW of this dying Cb. The focus of the activity was just to the north of Escalon and Oakdale, so once I was in Oakdale, I turned left on Hwy 120 from J-14 and headed west towards Escalon.
In Escalon, I saw the first lightning flash from the redeveloping storms at 1925. From here I could clearly see the trend of storms going up to the NW and training off to the SE. I continued west on Hwy 120 to Manteca. For the most part, I was able to stay out of precip - Hwy 120 seemed to be the rain/no rain line. I did get into some lgt-mdt rain from time to time, and even some 1/4 inch hail between Escalon and Manteca at 1937.
By the time I had gotten to Manteca, I hadn't seen any funnel clouds. I had to decide whether or not to go back home or continue the chase. Towers continued to build to the NW towards Stockton, and occasional in-cloud, cloud-to-cloud, and cloud-to-ground lightning flashed from storms to the north. There was still a little bit of daylight left, so I turned right on Hwy 99 and headed north towards Stockton to see what happened there. But by the time I got to Stockton, darkness had set in - and there was little chance of seeing a funnel. At the Mariposa Rd exit, I turned around and headed home - and this is when things got interesting.
As I drove on the Mariposa Rd overpass, a brilliant green cloud-to-cloud lightning strike lit up the sky directly overhead, followed by very loud thunder. Once southbound on Hwy 99, I encountered numerous pockets of heavy rain and 1/8-1/4 inch hail between 1955 and 2000. The worst conditions were between Stockton Airport (SCK) and the French Camp Rd exit at 2000. Here, extremely heavy rain and 1/4 inch hail reduced the visibility to near zero. There was almost enough hail to cover the road. At the same time, the temp was 43F, and winds were out of the WNW around 20-30 mph. (NOTE: SCK reported 3 mi vis in small hail, light rain and thunder with 48F temp and winds NW 12 mph gusting to 22 at 1958. Temp fell to 43F at SCK by 2014) Conditions improved dramatically S of French Camp Rd, and didn't I encounter any more rain or hail the rest of the way home.
Sacramento TV stations showed footage of some odd-looking funnels in the Escalon-Oakdale area Tuesday evening. One funnel was vertical and cigar-shaped, extending about 40% from the cloud base. There was a slightly thinner, longer funnel slanted at a 45-degree angle in front of the vertical funnel. The two funnels together formed what looked a little like the letter "X". Hard to judge from only a few seconds worth of footage, but I'd imagine the vertical funnel was the dominant one, and it was drawing the other funnel in its rotation (therefore causing the slant). Incredible week in what's been an incredible winter/spring....