Why does the app show rain every hour and every day when there is no rain anywhere?

You may have the wrong city selected.

Assuming your weather app is set to your location, it will report precipitation as a probability, such as “rain (40%)” That is a guess based on a weather model for your area. The further in advance you are looking the less will be the accuracy of the forecast. For example, a forecast for 3 days in advance may be way off, because the weather pattern and “steering winds” can change. A forecast the same day will be more accurate, but still depends on local conditions. And rain (40%) means that there will be rain somewhere in your general vicinity, but the probability of reaching you is only 4 chances in 10. If you would like a more detailed explanation I suggest getting a book on weather, or try ChatGPT or Google Bard.

WTH, I agree with you. This app until two months ago was fairly accurate. In Houston we have had the heat ridge parked over us and weather forecast was 0% chance of rain. Yet the weather app would show 40% - 60% chance of thunderstorms for the hourly forecast. Today for example, local forecast is for 60% chance of rain and weather app showed 0% this morning. Go figure.

Very helpful