I think your aside is a pretty big point...
ShowerThoughts
Sometimes we have those little epiphanies in the shower.. sometimes they come from other places. This is a home for those epiphanies.
As you pointed out, your phone doesnt have a thermometer. Or, it does. But it is for checking for overheating. But if your phone tried to measure ambient air temp, it would actually measure temperature inside its case, temperature in your pocket, temperature of whatever it is sitting on, etc.
And even if it did have this function, I typically don't care about the current temp. I care about what temp it is going to be, or if it will rain, etc. I want a weather forecast, not information about the weather around me
The sensor for your car is usually hidden behind the front bumper and has fresh air blowing over it as you drive to give an accurate measure of ambient temperature. What would your phone be measuring? Your body temperature if it’s in your pocket. The temperature of the battery is going to spike when in use or charging. Turning the screen on even for an instant to check the time is going to significantly spike the temperature. ANY use of the CPU/GPU is going to get hot. Nowadays the whole phone is a heat sync to dissipate heat generated by everything inside. There’s probably a dozen other things I haven’t mentioned that would make this a bad idea.
Aviator here: I want to see the prog charts and the goddamn GOES imagery. Get this computer-generated Accu-Weather What Are You Doing Step-Meteorologist monkey wank out of my goddamn standard briefing.
As a non-aviator, I don't know what any of that shit is. As the son of an aviator (my father had a pilot's license when he was younger, but he didn't keep it as I guess you have to fly so many hours a year to keep it), I want to help you, but I'm not sure I can.
I was given this link a few years back, and I've kept it, though I rarely check it. I just did, site is still up. Is this closer to what you want? https://www.ventusky.com/ If not, sorry; again, I don't know what all that means, but someone said it was a different/better kind of weather app/site.
Prog charts, or prognostic charts, are these:

Large scale picture of what the weather is doing including the positions of pressure systems, fronts etc. You've probably seen some of the symbology used on television weather reports. Prog charts are often prepared as observations and as forecasts.
Geostationary Orbital Environmental Satellites are a series of weather satellites operated by the United States that sit up there in geosynchronous orbit and take pictures of the Earth's atmosphere at various wavelengths, providing up to date gods-eye view of the weather a hemisphere at a time.
When I went to flight school, a lot of weather data, both observations and forecasts, were delivered to pilots in a heavily abbreviated text format intended to be distributed by Morse code or teletype. Pilots would get these products either through a Direct User Access Terminal System, or have them read to them during a briefing from a Flight Service Station. Here in the age of the internet, a lot of that has been replaced with internet-based graphical data, and they want to mix things together in strange ways, while making it more difficult to access raw data like GOES images and dopplar radar images.