Every year is different. Most likely the road will be closed. I got there in May of last year and wasn't able to get to McDonald until the end of May. Montana is also having a pretty rough winter this year.
The Village is almost always kept clear and by April some of the shops may be open. The chance of getting any further than the walk of cedars in April are very slim. Are you coming to Montana to tour or specifically to Glacier? If you specifically are comimg for Glacier you should reschedule.... With our snow this year it is completely possible that the pass will not be clear until June.
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