I think it's because the programmers' of ASOS knew their could (would) be rapid fluctuations in temp based on design/automation. -- thus a 5 minute avg. Why it hasn't been reprogrammed to account for this is beyond me. But 99.9% of even weather people don't know about the 5 minute avg and it's almost like they don't want people to know. But that's just me. Many times when I check the one minute screen as show above - it shows an "odd temp" for a minute that makes no sense under calm atmospheric conditions (from jet exhaust((no jet exhaust in below example)) or whatever but always in the high trend, never low) - many examples. Here's is one from last June-

Okay. I’m tired of the cold.

Been a nice trip here so far. Sunny yesterday but cloudy and gloomy today. Tomorrow looks nasty so it will be a nice day to do nothing. Rest of the week looks fantastic

Yeah avg snowpack for march is like 38” (sawce)

YVR had not had a goose egg since 1957-58 before this year.