Who knows how to forecast the future weather in advance? What I want is the weather on May 5th, 6th and 7th to be accurate.

Now, because of science and technology, it can be advanced by about 20 days in theory, because it can be analyzed according to previous meteorological data and climate phenomena in recent days. You can ask the local meteorological bureau if you want to know. I wonder if you have this service there. I can provide it here, because considering that some special projects need the climate data of the day, we can pay for consultation at this time. If it is purely for personal needs (such as traveling), you might as well call the meteorological bureau. If they don't provide it, if you have time and convenience, you can go to the library or archives bureau or check the local climate data in previous years online, which can generally be found for your reference.