Georgia found the alien hiding in her barn after she finished picking green beans for tonight’s supper. The alien wasn’t terribly frightening or intimidating. Or, even particularly alien looking. He just looked different enough so you knew he wasn’t from any place on earth.
After a few moments with her mouth gaping open like the Grand Canyon before it collapsed, Georgia took a tentative step forward. She reached behind the alien, and grabbed a small basket for the potatoes still out in the garden. With the basket firmly in hand, Georgia marched out into the frigid August sunshine.
As she shivered with the cold, Georgia wistfully thought of traditional August days with heat so suffocating you couldn’t

I seems really weird that she sees the alien, is surprised for a moment, then walks out of the barn thinking of something else (but again, you might have a good reason for this)

I would read a little further to see 1) why was her reaction to the alien so mild and 2) why is it cold in August? and 3) was there a good reason for not describing the alien 4) why did the grand canyon collapse?

Nitpicks:
"Georgia found the alien hiding in her barn after she finished picking green beans for tonight’s supper.": The use of "tonight's supper" with the past tense seems odd. Should it be "that night's supper" or something?

"The alien wasn’t terribly frightening...": I would use "it", you used "The alien" on the last line.

Do you mean her mouth gaped open like the Grand Canyon, but then collapsed? It sounds like collapsed refers to the Grand Canyon, which makes it a simile of an unknown event, and that's odd. (I wouldn't say it was completely verboten--P.G. Wodehouse could get away with it. But it's odd as it stands.)

My take:

quote:

---

Georgia found the alien hiding in her barn after she finished picking green beans for [tonight’s<--I don't think you need this word. It confuses tense, too.] supper.<--Nice hook.] The alien wasn’t [terribly<--Eww. Adverb. Kill it, kill it!] frightening or intimidating. Or, even [particularly<--Ack!] alien looking.<--[How? What did "he" look like?] He just looked [different enough<--Can't picture this. Make me..] so [you<--Me? This reminds me that I'm reading, instead of taking me deeper into Georgia's PoV.] knew he wasn’t from any place on earth.
After a few moments with her mouth gaping open [like the Grand Canyon<--[PoV?] [before it collapsed<--Unnecessary. If it was a "few moments", we assume her mouth didn't lock itself that way.], Georgia took a tentative step forward. She reached behind the alien, and grabbed a small basket for the potatoes still out in the garden. With the basket firmly in hand, Georgia marched out into the [frigid August sunshine<--Eh? Where is she at, Siberia? Ukraine?].[Eh? She just sees something so strange that she stares, mouth agape, but then reaches past it, without a word, and just goes about her chores? Doesn't seem real.]
As she shivered with the cold, Georgia wistfully thought of traditional August days with heat so suffocating you couldn’t[Why isn't she thinking about the "alien"?]

---

1) If you hook us with Georgia discovering an "alien" you have to let us know:

• How she knows it's an alien. Specifically what she sees that determines that.
• How she feels about that. She might show the alien ambiguity, but I don't buy that she'd feel nothing.
• Why the alien is relevant. For instance, if you were walking through Central Park, you might find a dead body. Regardless of how many bodies have been found in Central Park, you would feel something. Fear? You could have been there at the wrong time; it could have been you. Sadness? It could have been a small child, or an old man that you'd regularly seen joking over a game of chess. Anger. No matter what you had felt, the event--and the feelings--would change the course of your day. That is where the stoy lies. Not in potato picking.
  

2) The oddness of the "frigid August sunshine" alludes to an uncommon milieu. We need to know where, if that is so. If it's not, you may want to rethink it.

Hope this helps.

I guess some people are reading it as her mouth gaped open like the Grand Canyon and the her mouth collapsed. If that's what you really meant, then also know that a collapsed mouth makes me think of a mouth with broken bones and teeth, not a mouth that suddenly closes.

There are probably ways to do this, tease at the world your character lives in, that are a little more subtle than the character thinking about august heat. Plus, just a plausibility point, if it's frigid in august and she's getting a basket to pick potatoes, and has just picked green beans, does she have a greenhouse? Potatoes in cold weather, OK, green beans, not so much. They die w/frost. At least the ones in my yard do. Actually, they die much earlier than frost since they peak in July/early Aug and frost doesn't hit here until early/mid Oct. But I digress.

I guess this makes me interested.

Well done!!