Garmin should drop weather because they just don't care about it

If they are taking humidly into account then that resolves the problem with head acclimatization. I don't really see it in the my data in spite of how hot is is.  They should also take how hot it is and one's head acclimation into account with regards to LOAD (it's a stress) and VO2max (however flawed that metric is) because the heat will reduce the pace one can run.  Maybe with higher heat acclimatization the pro-rating of LOAD and VO2max could be less. 

Cloud cover / sun factor is also something I miss in the feature: running in July with 22 degrees (celcius) and full sun is much more straining than 25 degrees and full cloud cover, but only the latter takes heat acclimitisation into account.

Ultimately, the effect of weather on performance comes down to temperature, humidity, solar radiation and wind (THSW). This is the gold standard for giving an accurate 'feels like' temperature, but unfortunately apps/forecasts also use that term when they only take some of the HSW factor into account, but not all of them. Temperature and humidity are self-explanatory: the higher the humidity, the hotter it feels. Solar radiation is basically how sunny it is, but that's location specific; I could run on the one side of the road in direct sunlight and the THSW temperature might be 23*c, or the other side in the shade and it be 19*c. It's a similar story for wind, which can vary in speed, direction and temperature every time you turn a corner.

So, in short, any generalised temperature (whether purely temperature or adjusted 'feel like') is only going to be an approximation that could vary significantly through a single activity. As an example, in my back garden yesterday over a three-hour period where the temperature was a pretty steady 18*c, the THSW temperature which would have affected performance varied between 17-23*c due to HSW changes, which could have been different from just the front of my house. The trouble is I don't see how Garmin could know the localised factors specific to an activity to make heat acclimatisation data any more accurate. Of course, there's the Tempe sensor but AFAIK that only senses temperature and I don't think Garmin uses Tempe data for heat acclimatation. There's also things like the CORE sensor, but as that detects core body temperature and specifically not ambient temperature, that's not of much use here. Maybe just relying on the law of averages means that Garmin's current approach is the best option.

I don’t understand what is wrong. Currently I am in Italy and weather is absolutely wrong. 21 vs 33 C. I have tried set up iPhone location data and fixed position. Nothing works. 

Same for me (android 12)

Widget on whatchface showing 32c while i'm in the mountains with 19c temperature

Funny thing is that weather forecast looks correct.

When restarting the phone the widget correct itself for a bit, but then fail again

Setting fixed location did not help

For example right now

https://i.imgur.com/E4sAtHW.jpg

It shows 31c.... Bot he know himself they today it is max 19C and min 8C