Sorry I meant she might have quit for this year. They will quit laying before the fall molt, which will generally start at the end of August and go to December. Some start the molt earlier than others.
She also could be taking a break which many hens do when it gets hot out. They will resume...
Could be something is wrong, or it could be she's starting to shut down for the season. If she's acting normal I wouldn't worry, if she's acting off there could be something wrong internally, than you would have to find a vet to have a look at her.