A man who died alongside his wife and 1-year-old daughter in August on a California hiking trail reportedly sent a frantic text to a friend before the family succumbed to heat exhaustion.

In October, Mariposa County officials determined that Jonathan Gerrish, 45, Ellen Chung, 30, and toddler Aurelia Chung-Gerrish died from hyperthermia and probable dehydration. Before dying at Hites Gulch, Gerrish wrote a text to an unidentified friend asking for help, according to The San Francisco Chronicle.

“Can you help us. On savage lundy trail heading back to Hites cove trail. No water or ver (over) heating with baby,” he reportedly wrote — but the text was never received.

Officials announced the family’s autopsy results in August. On Thursday, police provided their final update on the case and publicized Gerrish’s cell phone data — which apparently supports that he and his family died from hyperthermia.

The Chronicle reported that the text message Gerrish wrote to his friend on August 15 was never delivered because Gerrish did not have reception on his cell phone, which was found in his pocket.

Previously, Mariposa police dispelled speculation that toxic algae, specifically Anatoxin A, killed the family. Local reports indicated that the Merced River, not far from where the family was hiking, was closed to the public the same month. However, water from their bladders was determined to have come from a tap or bottle.

Police explained that Gerrish used an app to map out their hike, but it did not account for the trail’s mileage or changes in altitude.

On August 15, a witness spotted the family’s truck driving toward Hites Cove Trail Head, before seeing the car parked at the location. It was approximately 72 to 76 degrees in the area and the elevation is about 3880 feet.

The family is believed to have hiked on foot 2.2 miles from Hites Cove Trail Head to U.S. Forest Service Trail 20E01.4 — where the elevation is 1930 feet with estimated temperatures were between 92 and 99 degrees. They reportedly continued 1.9 miles to the Savage Lundy Trail intersection — where the elevation was approximately 1800 feet and the temperature was 99-103 degrees.

The family then embarked two miles up a steep incline on the trail, where temperatures reached 107 to 109 degrees during the early afternoon but dropped to as low as 89 degrees between 4:50 and 8:50 p.m.

The family was found dead on August 17, two days after they embarked on the hike. They were reportedly discovered on a hill that had no shade due to a 2018 fire.

The family dog, an 8-year-old Aussie/Akita mix, also died on the hiking trail. Police said the dog’s official cause of death is undetermined, but its remains and other evidence suggest it also died from heat-related causes.

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[Featured image: Jonathan Gerrish, Ellen Chung, and Aurelia Chung-Gerrish/KTVU]