may happen is more likely than something that might happen. You’re more likely to get wet if the forecaster says:
It may rain to-day, than if she says: it might rain
Please note that “May" is mainly used for a question and "might" for a statement.
You say: "May I go to the bathroom?" NOT "Might" I go to the bathroom?.
Also remember that might is the past tense of may. So you have to use might when you are referring to the past. For example, even if it's likely that your friend went to a party last night:
You shouldn't say, “My friend may have gone to the party.’ (Not correct)
you should say, “My friend might have gone to the party.”
To learn more about the difference. Please read:http://www.usingenglish.com/forum/as.../27115-ms.html,
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