Ford focus stalling

I have a 2000 ford focus, inherited from my grandmother 3 years ago. It arrived with 27,500 miles and today it has around 68,000. Lately, I have had three experiences where, on either a damp or chilly day, I will start the car, put the car in reverse or drive and as I step on the accelerator, it stalls. When this happened the last two times, I waited anywhere from 5 ? 15 mins, started the car and drove away without incident.

Today, a damp day, when I stepped on the accelerator, it stalled and many hours later it is still parked where I left it; it turns over but does not start. This was 6 hours ago. Perhaps related: I have also had the car stall on me, while accelerating onto a highway (car started after waiting 5 mins) or feel as though it was about to stall as I came to a stop.

Any thoughts as to what may be happening?

I got a 2001 ZX3 with a manual transmission and it is starting to stall when I back up also. Do not have the wait problem you have starts right up. Hutch KS. I have 99k miles.
Mine chuggs and/or misfires on heavy acceleration in 2 & 3, starting to do it in all gears.

Problems in rain or high humidity could point to moisture in distributor cap or old spark plug wires. Particularly under hard acceleration conditions. Athough this would cause more of an engine misfiring rather than a complete stall.

Any check engine lights on?