While the record-melting Sierra snowpack has created some dazzling waterfall imagery, it also carries a high risk for floods and fast-moving rivers at Yosemite National Park. These treacherous waters can run exceedingly cold with sneaky strong currents, and there is cause for alarm now that the National Park Service has issued a Missing Person Alert for a 24-year-old enlisted Navy member who went out hiking at Yosemite last Wednesday and hasn't been seen since.

Alexander Joseph Sevier of Virginia was staying at Housekeeping Camp in Yosemite Valley, and his whereabouts have been unknown since the morning of May 3. Seen above, Sevier is described as 5-feet 6-inches tall, weighing 126 pounds, and with black hair and brown eyes.

“People in the camp said they saw him Wednesday morning, going out on a day hike, and he just hasn’t been seen since,” said National Park Service spokesman Scott Gediman, according to the Chronicle.

Sevier had been scheduled to check out of the camp on Saturday, but did not return from a hike. Adding to the concern, his possessions were still at the camp Sunday and he missed a scheduled flight back to Virginia.

Anyone with information on Sevier’s whereabouts is asked to call (888) 653-0009. Campers and hikers are also being encouraged to exercise caution around the Merced River, which is running much cooler and with faster currents than normal.

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