Weather Or Not...

I am considering knitting a weather scarf [or blanket] AKA known as a Temperature Scarf. Mags and friends over in NI  were engaged in this project back in 2018.
The idea is that you measure the temperature every day for a whole year at a given time [8am, midday] in a given place. 
And you prepare a chart assigning a different colour of wool to each band of temperatures.
Some people choose a rainbow palette, others go for shades of their favourite colours [blues, autumnal, green etc]
And you knit a row or two of the relevant shade so that your resulting scarf shows the changes in temperature through the seasons.
[Some blanket makers produce a square per day]
The results are quite lovely. 
But the more I read about these projects, the more I realise how important it is to plan and prepare thoroughly first.
For instance, a number of people haven't considered that there will be at least 365 rows in your finished piece - so do a tension square to get an idea of the finished length.
Other people [mostly in the warmer states of America] have moaned that their scarves have only included a small number of colour changes. They had forgotten that where they live, the annual temperature is fairly constant so they need narrower temperature-bands to guarantee a good range of colours. 
At least Britain is seasonal, with warm summers, cold winters and spring and autumn both being mild. 
I'm still working on what sort of colour mix, and should it be scarf or blanket? 
I know I will need a logbook - simply because some days I won't get round to knitting my row, and I must make a note of which colour I should have used on Wednesday and Thursday.
But the thing I have yet to source satisfactorily is a temperature measuring system. There are various apps out there, where you can select location and daily time, and the temperature will be regularly sent to your phone. But which one is the best for this? 

If you have knitted a weather piece, would you let me know how you measured the daily temperatures, please?
The final thing after all this planning will be to buy the wool. And I'd said this year I was not going to spend any money on craft materials.

But I've sneakily got round this one, by asking family members to contribute to a Wool Fund as my Birthday Gift. Liz, wise as ever, said only if I promised to get decent wool, not cheap acrylic stuff. If this is to be a lasting project, it needs to be something worth keeping. She is absolutely right - quality matters.


I'll update you on my progress!