I don't know what "very possible" means in relation to another's comment, but I was at fire level 12 and still didn't survive the rain for more than a few seconds... :(
Do you mind sharing a screenshot of your spawner layout? I think some fuels and builds work better at feeding the fire during the rain in the current balancing, I'd love to address this! I think if you’ve reached 12 it should only be a few upgrades away! Thanks for flagging this :)