Can you teleport outside? Sure.
Is it safe? So long as there's no rain to smudge your diagram it's basically as safe as doing it indoors. And in Lucien's defense there wasn't any rain at all, right up until the last sylabble of the incantation.
"I um. Am not actually a fan of assassinating world leaders as a general rule but if it's important to preventing tens of millions of deaths I can make exceptions I suppose."
"I don't actually know how much the geopolitics turn on specific dudes and you probably want to at least read some books to both confirm that the dudes suck and that you don't have a better lever. Maybe you're actually in a great position to create a Jewish ethnostate somewhere in Canada and get industrial technology accelerated so fast that Communism doesn't kill a ton of people. It's just, you know, for the next couple hundred years every conversation about time travel inevitably derails on 'but of course you've got to kill Hitler, first thing', so it popped into my head."
"I could plausibly set-up a small Jewish ethnostate somewhere if I dropped everything else - though I doubt I could get it stable enough to survive people finding out I'm a sorcerer so it's not very viable. There's a famine in the Soviet Union right now that I think an industrial revolution is too late to fix. Also wait did you say next couple hundred years."
"Where I'm from it's 2159. - or, it was when I left, I've been gone for a while, I guess it's like 2161 now."
"No, I spent a while conducting a war against an evil god with some cyborg Elves in another universe."
"I can move figuring out a way to neutralize evil gods up on my to-do list if it's particularly bad. Not that I can definitely do it but up till now I've been prioritizing other problems over my world's relatively unsuccessful evil gods."
"I believe he is now neutralized. Getting him that way was awful but I have no specific reason to think it won't stick."
Lucien takes a moment to gather his thoughts.
"Uh, back tracking a bit - I'm interested in technology from the 22nd century if it's on offer."
"You probably don't have to go through me about that if you'd rather not, Bar can get you books."
"Bar, what's up with that." He gets a napkin. "You can tell him stuff about my dimension if you want. But also, like, lots of places are probably having the 22nd century, it doesn't have to be mine."