Where Tahoe spots come from
Water spots form when water dries and leaves behind what was in it: minerals, dirt, pollen or road residue. In South Lake Tahoe, the sources are a little different from the valley:
- Snow melt dripping off roof edges, eaves and pine branches onto parked cars
- Slush and de-icer spray that dries into a gray, spotty film on doors and glass
- Lake water left to dry on the car after loading a boat, kayak or paddleboard
- Spring rain mixed with pine pollen, which dries into yellow-ringed spots
- A home rinse with a hose on a sunny day, left to air dry
Why they bake in fast up here
At about 6,200 feet, the air is thin and dry and the sun is strong. A drop of water on a dark hood can dry in minutes on a clear day, even when it’s cool outside. That leaves less time to wipe it off before it sets.
Cars parked under the drip line of a roof or a big pine get hit over and over as snow melts during the day and refreezes at night. By spring, the hood, roof and windshield can be covered in rings.
Dark paint shows it the most. A black or deep blue SUV parked under a dripping roof edge can be covered in white or gray rings after a single sunny week.
At first, spots sit on top and come off with the right product. Left long enough in the sun, some can etch into the clear coat or bond to glass, and those need more work.