Did you recently move them outdoors? Or just plant them?

If so, could be windburn, sunburn, and/or leaf drying.

Can you post an image or two?

I will take pictures this evening and post them. The squash was recently planted from seedlings but the cucumbers were new sprouts from seeds.

Did you get a freeze during that cold front that blew through last weekend? If so, did you cover them adequately? If the answer to the first question is yes and the second is no, then it's most likely frost damage. It shows up as thin-looking leaves (and parts of leaves) the next day that turn brown and crispy over the next couple days.

We didn't get a freeze but it did get chilly. The leaves on the cucumber plants are white and thinning. This evening when I went out to check some of them had wilted and were on the ground. I have pictures but can't figure out how to post them and link them to the posting.

The gray sounds like a mold. How much rain/watering has occurred in the past week or so?

They are planted in a top soil compost mix that is very loose. I was afraid they were getting too dry so I have been watering them every other day or so with a sprayer. Yesterday I watered them with the sprinkler for about 45 minutes or so. They didn't seem to be overly wet though. That soil seems to dry out very fast. It has been very windy and I was afraid that was drying them out also.

Did they look like this mine snapped back and are growning well now .
{{gwi:31650}}

I have had this problem with all of my vines. It has affected all of my gourds, cucumbers, squash, pumpkins. I think it is a fungus either Colletotrichum orbiculare or Alternaria leaf blight. Is there any cure for this or should I just start over? Will I have this problem if i dont treat the soil? Anyone?

Here is a link that might be useful: Leaves turning brown

Environmental stress -- heat, breeze/wind, lo humidity -- compared to what they previously had.

Not a disease of any sort.

Temporary protection is likely to help. Try row covers.