The Fairfield Health Department issued the alert on the morning of Sunday, July 17.
"Please be advised that there are reports of stinging jellyfish in the waters at Jennings and Penfield Beach, but could be possible at other beaches," the department said in a Facebook post. "The presence of jellyfish can vary based currents, wind and tides, please be cautious when swimming."
Swimming at the beaches remained open as of the update from the health department.
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