Raid boss stats & weather

That's a really good question, I'd like to know the answer too. My guess is it's too soon to know, but I'll keep my eye out for results.

FYI, I think there can be overlapping weather patterns so it may not matter. Today I saw a boosted spearow right next to a boosted jigglypuff.

If it is clear when the egg spawns, rainy when the boss comes out, cloudy when you start the fight and snowing during the catch chance, you should consider filing a bug report or moving to another city. Unless you are in Snow City, Jurong East, Singapore. As someone who lives on the other side of that island nation, I assure you that the game cannot keep up with our rapidly-changing weather.

I read somewhere that the weather only updates once an hour. Don't know if that is true but it would mean that there could only be one possible weather change in a raid.

I would suspect though when the first player creates a lobby, the weather is probably locked in for the duration of at least those players' fight and catch sequence.

Can't specifically answer this, but I just did a Cloyster raid, hoping that with the rain I'd get a buffed one. Took me 3 tries (remember, high CP trumps better matchups), and on the third one, the weather had shifted to partly cloudy. Confirmed when it started calling up Golems in auto select instead of Jolteons. Got a regular level 20 catch after the raid. It was more of a 'Can I do this' thing than anything else, so I'm only a little miffed at the weather change. Now, if I had fought to take down a Ho-Oh and lost the weather buff, ....