Unrelenting rain appears to be washing away chances of finding a hiker lost on Y Mountain since Sunday.

Low clouds and a skiff of snow Wednesday morning covered the rocky slopes overlooking Provo where Aaron S. Lowe, 25, is presumed missing. Temperatures dropped into the low 30s overnight."With the weather horrible, the chances of him being all right are getting slimmer and slimmer," said Provo police spokeswoman Karen Mayne.

Rain showers interrupted search efforts for several hours Tuesday, and searchers had yet to return to the mountain Wednesday morning. They'll hold off until the weather breaks, but they don't plan to give up.

"As long as we have any viable clues, we'll keep going," said Lt. Stan Eggen, head of the Provo Police Mountain Rescue Team.

Scents that search dogs sniffed out Tuesday are now diluted from the water. Eggen said search teams found no physical evidence of where Lowe might have hiked, leaving them to look using common sense. "You get up there and say, `Which way would I go?' " he said.

One of Lowe's best friends, David Hymas, joined the search for 14 hours Monday and was anxious to get on the mountain again. He described his former roommate and skiing buddy as "pretty much on top of the world."

Lowe, a senior at Brigham Young University and a native of Woodbury, Minn., was due to leave Provo in a week to prepare for law school this fall at the University of Minnesota, Hymas said.

Lowe's wife, Jacquelyn, gave birth to a boy about 10 days ago, and the couple has an 18-month-old daughter, he said.

Climbing over the top of Y Mountain "was one of the last things he wanted to conquer" before leaving town, said Hymas, who along with Lowe and some friends scaled Squaw Peak just before leaving on LDS Church missions a few years ago.

"He just likes the outdoors," Hymas said.

Lowe, wearing an orange T-shirt and khaki shorts, started up the trail about 2 p.m. carrying a backpack with food and water. He called his wife from his cellular phone at 3 p.m., telling her he was some distance south of the Y and would continue up the mountain. He also told her he would call back for a ride home when he was down.

Jacquelyn Lowe waited all evening, but the call didn't come. She reported her husband missing at 12:25 a.m. Monday. Searchers' repeated calls to Lowe's cell phone went unanswered. Authorities surmised that Lowe might have been injured in a fall.

Dozens of would-be rescuers, including a Utah Highway Patrol helicopter with an infrared camera, two jeep patrols and nine searchers on horseback, have combed the steep, brush-covered mountainside the past two days.