mev

Here is what I do. It depends a bit on the specific weather forecast, e.g.
* if it says "40% chance of thundershowers, 0.1 inch accumulation", then I just go and hope for the best.
* if it says, "80% chance of rain, 0.75 inch accumulation", then unless I have other constraints, I'll cancel a weekend overnight.

I frequently do these sorts of short weekend overnights here in TX during the cooler months. Reservation times on TX State Parks are so long that I reserve a weekend before knowing specific weather forecast.

I've been wrong once or twice and had a heavier rain storm but those turned out to be OK. It has helped that (a) I can occasionally shift times, e.g. wait to depart until something passes (b) campgrounds sometimes have a covered place where I can pack up before departing (c) once I'm in my tent, all is pretty dry (d) it is rare that central TX has particularly cold rain in contrast to other places I've lived. I've also had multiple weekends where the forecast showers never materialized.

On the weekends when a major front is forecast to go through and predictions are for 0.75inch or more of rain and more a question of "when" than "if", then I'm more inclined to make second thoughts on cycling a rainy weekend.

On weekends when I'm pretty sure I'll cycle regardless of the weather, then I might instead make a motel reservation. For example, I bought some train tickets recently that bring me to Longview TX and three days later back from Texarkana, AR/TX. Only 90 miles but I'll cycle between them unless the weather is horrendous (e.g ice storm), so I have motel reservation as well as train reservation.