What do you folks do on a tour if a couple of days heavy rain kreeps in?
In all seriousness, California has a Mediterranean climate, which means it only rains in winter (mostly) and generally stops by April.
No rain for six months is the norm over the summer. We only chance rain during the early-spring tours- March, April, and that's about it. Maybe our late-season tours in October. Normally no rain till November or December and our tour season is over by then. I do have fair-weather riders who are regulars (and local) and will cancel if the weather outlook is lots of rain. I'm a bit of a diehard rider and don't care if it's raining, snowing, or cold. I hate riding in high heat (over 100 degrees) as I'm always in full armored leathers & leather is hot. I'm also wearing a Dainese air vest and the air vest makes you even more hot. Worth noting, the timing and sequencing of my tours are all centered around the seasons. In March, we ride desert regions (ie Death Valley), in spring, we ride the mountain foothills below the snow line, June we head over the mountain passes, summer we head to the ocean where it's 20 degrees cooler. We have had tours where an inch of rain was predicted for Sunday, so the fair-weather riders all cancel and the diehards all ride, and we just rode home a day early. Another time I had our lodging booked at a place at 4000 ft and that's the snow line in the mountains, huge storm was predicted, and I moved the tour region across the state just days before the scheduled ride. We still rode, but I moved the entire tour route away from the storm where there was no rain, good thing, my lodging place got 4 inches of snow that weekend.
Heavy rain (ie flooding) here is actually quite rare, and the 2023 winter we've had is likely a 50-year-event (once every 50 years?) We've ridden three tours already by early-April, and we've gotten lucky all three times to ride in-between the waves of rain. Next ride is this coming weekend and 70 degree temps predicted. So just plain luck is also a factor.
If it rains, I just put on a rain suit and go.