So I know how they get to the sky and all that, but when exactly do they come out of the sky.

I am assuming that the mythos card has to have the symbol for that monster…..but if there are no investigators in street locations, does that mean it will stay in the sky? So potentially it will never come down if there are no mythos cards drawn with that monsters symbbol when investigators are in the street?

Or will the flying monster come down in a non street location to th elowest sneak investigator?

Mythos cards which reveal a dimensional symbol of a monster in the sky will move to a street area containing an Investigator, which the Investigator will Fight or Evade during the next Movement Phase . Additionally, if you have expansions, a Gate Burst will cause monsters to leave the Sky and find unsuspecting Investigators in the street. If there are multiple Investgators , they'll visit the one with the lowest Sneak score.

So if there are no investigators on a street….they will stay in the sky?

Yes, they remain in the Sky. As per FAQ, pag 12:

The Sky and Flying Monsters

Q: Please clarify how flying monsters move.
A: Flying monsters move according to the following rules:
1. Flying monsters only move when their symbol comes up in the Mythos Phase, just like other monsters.
2. Flying monsters will not leave a space that already contains
an investigator.
3. When a flying monster in a street area or location moves, it will either move to an adjacent street space that has an investigator in it, or failing that, move to the Sky.
4. When a flying monster in the Sky moves, it will move to any street space on the board with an investigator in it. If there’s more than one investigator to choose from, the monster moves into the space of the investigator with the lowest Sneak value. If the investigators’ Sneak values are the same, the first player chooses which investigator the monster moves toward, as usual. If there are no investigators in a street space, the monster remains in the Sky.

You're right - they are 'stupid flying monsters'.

Monsters on the streets get a chance to spot you as you go past (i.e. you may have to evade them or fight) but the flying monsters are high up in the sky circling the city and never bother to look down during the movement phase.

And they never bother to glance down into (mainly) open air locations, so they will never spot you outdoors searching through the woods, playing in the Independence Square park or visiting the (previously-) Unvisited Isle.

It would almost make sense that they had a chance to spot you when moving through the streets. As it is, you can often avoid stopping in the streets and end up with several fliers effectively stuck in the Sky, making Arkham movement a lot easier.

Stupid flying monsters.

Except the mi-go… some of them are quite clever. Although still not clever enough to look down during the movement phase…

Judgement Dave said:

Dammit, Jim! They're surgical bugs! Not kamikazees!

Perhaps genetically related to the Arkcam Asylum/City thugs WHO NEVER LOOK UP before I mete out SWIFT DARK KNIGHT JUSTICE, amirite?

Funny you mention that--I was hosting a game party where I was introducing Arkham Horror to my friends. We were playing the Game of Life first and one of my friends looks up and he's like, "Oh, let's play the Batman game next."

"Batman game? That like a drinking game? I don't have any Batman game."

"Oh--then what's the Arkham game? Arkham Horror is that like, Arkham City?"

"Oh! Erm--no, it's--nothing at all like Batman."

But now, thanks to you, Joe, I can say in all honesty, 'Yes. Yes it /is/ like Arkham. Because the monsters are about as dumb as the henchies in that game."

I've seen that particular confusion too. Perhaps not that strange since the batman stories really did take the name for the gotham mental institution from Lovecraft.