PANTHER JUNCTION, Texas (KTRK) -- Kicking off Fourth of July weekend, park officials are urging hikers to get off trails by the time temperatures reach 95 degrees, which is usually between 10 a.m. and 11 a.m.
The warning comes after an avid hiker and father was found dead at Big Bend National Park.
RELATED: Friendswood man found dead at Big Bend National Park after rangers find note about hiking plans
Now, his friend is sharing his story in hopes of keeping others safe. Dave Locke says he's still in shock after hearing the news that his close friend died while hiking.
"Richard knew the risks," Locke said.
On Tuesday, 54-year-old Richard Merrill of Friendswood died while hiking on the Marufo Vega Trail.
Park rangers say they found a note with Merrill's plan to hike from 7 a.m. to 2 p.m., with a request to notify the park if he hadn't returned by then.
"He was going to go on this trail, but was afraid it might be a little too hot. At the last minute, he decided to try and get it knocked out first thing in the morning before the heat hit. That was the last we heard of him," Locke said.
During a search and rescue mission, park rangers found Merrill's body about a quarter mile off the trail near the junction of the Strawhouse and Marufo Vega trails.
Big Bend National Park expressed its sadness on Facebook, and suggested that extreme heat was to blame.
"Richard was no dummy. Richard was very smart, very smart. In fact, he was the smartest person I knew," Locke said.
Locke, the creator of the Big Bend Chat Facebook page, said Merill was a moderator and a source of information for others.
"The level of experience that he had and the knowledge that he had, and he still perishes on that trail or in the park at all. The fact that he did, is a testimony to how dangerous that place is," Locke said.
Locke hopes his friend's story will keep other hikers safe.
Locke and the other members of the Big Bend Chat are working to set up a GoFundMe for Merrill's teenage daughter.
Follow Brhe Berry on Facebook and Twitter.
Park officials warn of extreme heat on trails after hiker found dead at Big Bend National Park