The weather on the summit is not easily
predictable. Which means it is impossible to predict whether you
will be able to view the scenery of Maui from the summit or not.
We visited Maui in April and we went to Haleakala the second day
of our trip. The weather turned out to be nasty, it was cloudy and
foggy and it was impossible to see anything. For short periods of
time the fog will part and you'll get a glimpse of the crater
enought to make you gasp and than it will all be covered in fog again.
So we decided to come to the summit once again and did so on the
last day of our vacation, seven days later. This time the weather
was glorious, sunny and clear and we were able to hike into the
crater and take beautiful pictures. There is one more thing that
I want to mention: just because you see clouds while driving up
the mountain, doesn't mean they won't clear by the time you reach
the summit so don't give up early.