It just bothered me because I live in the same area in terms of climate and knew it could not have been the reported 106/107 temp at 11 AM.
Please take my question off the list if you still have time to edit.
The actual temperature is a subject of much debate, but it matters less than folks think. At the lower bound it was hot enough to get him in trouble in under 30min of running.
this said I’ll lay out why I think it was hotter than the reading
Another commenter correctly noted that temps are often taken as shade readings 8’ or more above ground level. This means actual temps felt by a human will be higher usually, especially in exposed areas such as Philip’s route.
additionally the Pleasanton readings are for Pleasanton, not the ridge. The ridge and the small valley inside it are typically hotter, sometimes significantly so and reports from others up there during that timeframe (11am-1pm) that day all describe it as being hotter than the base.
personally I’ve noticed that temperature readings generally in the Bay Area lag actual temps by a few hours. Probably due to their being shade readings. When heading out for a run around 10am it’s almost always whatever temp the forecast says it would be around noon.
I took a run up there with heat gear and water last week on a shadier climb up (courdet) to check out a couple of spots we wanted to think about. It was 101f at the base. I felt fine with the temps until about 75% of the way up, then once I hit the exposed top it shifted into a serious battle to stay cool.
the lower bound of good temp readings for the time of Philips run starting is low 90s, it’s highly likely it was already at least mid to upper 90s. Philip could have experienced heat exhaustion in temps in the low 80s so this was already a danger zone.
regardless of base temp, by the time he was running through the hotter and exposed ridge portion at 11-11:30am he’s running in temps that were likely around 98-102f, and in the hours after that he would have faced temps of 110+ if he were still in exposed areas and 100+ in shaded areas.
It doesn’t matter if Philip got lost or hurt before or after the heat took it’s toll, the fact is the 48 hours after he went missing that park was baking and whether it was very soon into the activity or longer until the activity regardless eventually the heat would be a compounding problem.
personally, and I do heat train, I’ve had times I’ve cooked myself into trouble in only 20min when the temps were 80-85 and only 10ish above my usual climate by pushing a hill at the start of a run.
lastly, if Phil was shirtless, which we still have strong suspicion he was, then the sun and heat would have cooked him even faster. You lose the evaporative cooling advantage of sweat laden clothing, lose the ability to wet the shirt at a water source, and lose the protective barrier that reflects so much of the sun’s rays when in an exposed area.
Shirtless is possibly one of the components of why we haven’t been able to find him: since it diminishes greatly the ability of someone with heat illness to recover when reaching a water source and gives us far less material to search for once wildlife is involved.
