Device Temp -vs- Live Weather Temp

I wrote a data field that grabs both the local "device" temp from my Edge 1030 as well as Live Weather from nearby WX stations. I select the best temp for a hydration calculation. In some cases, of course, Device Temp is better, like anytime you are indoors (in an A/C or heated space), or really *almost* always when Dev Temp is lower than from a Weather Station (say the station is far away, or you are climbing to a high elevation).

But this shows the huge offset that device temps can have from reality. The 39 deg offset was while we were stopped for lunch halfway into a 109-mile ride, with my bike sitting in direct Florida sun. But even when moving, the typical offset mid-day was about 10-12 degs F. The offset started about 2 hours after sunrise.

I logged the data using println statements every 10 mins. Which is why the line graphs seem to jump a bit.

Anyway, we all knew about this but I found seeing the actual data interesting.

jim_m_58 over 1 year ago

For a watch, the internal temp is impacted by different factors, including body temperature, if covered by a sleeve, etc. Data from a weather station, by things like proximity to the location where it's measured, difference in elevation, etc.. For me, Garmin Weather isn't that accurate, OWM is better, while Weather Underground has the most weather stations

To get true ambient temperature, look at a Tempe Sensor, where you can move it around to keep it out of direct sunlight

DaveBrillhart over 1 year ago in reply to jim_m_58

For me in Florida, Weather Stations are plentiful and elevation isn't an issue, so it works great. I can't count on users having a Tempe Sensor and my data fields are focused on cycling with Edge devices that are very susceptible to sun-influenced device skew. So I have a User Setting to allow a user to select temp source.... Live, Device, or User Value. And if they select Device, I use a Smart Offset calculation to handle Device Temp skew during daylight hours and outside activities. They can enter a Peak Offset (default of zero), to manage the peak offset to apply mid-day. Best I can do.