The outside wood rail was painted with white latex paint. It dried for two days and then it rained. The paint cracked and blistered. Once the sun came out and dried the paint it looked fine. Every time it rains the paint softens and blisters. How do I fix the problem?
Two things might be happening. One, water is getting underneath the paint. This will cause the bubbling. Two, the paint didn't cure enough or properly before exposure to the water.
I recommend repainting when the weather is dry for several days. Remove any loose or peeling paint and this time check every joint for caulking. Apply a primer before painting.