Most spots are mineral deposits left as rinse water evaporates. Weather decides how quickly that happens.

Two things matter most

  • How fast water evaporates (sun, heat, wind).
  • How much mineral is in the water (hard water = more risk).

Practical drying steps

  • Dry top-down. Use a large microfibre drying towel.
  • Don't rub dry — blot/drag gently to reduce swirls.
  • Open doors/boot briefly to catch drips before they run down clean paint.

If the forecast is hot and still, aim for shade. If it's breezy and mild, drying becomes much easier.