According to this, there might be.

"Do you ever see how ingenious and sharp people on the internet can be and think, "Wow I'm not as smart as I thought I was?" Today was one of those days, as the detectives on NeoGAF stumbled upon a pattern which has proven to consistently predict imminent Nintendo Direct presentations.
Here's the deal. On Nintendo's official website there's a page specifically for Nintendo Directs. On this page, a blank slot reportedly always opens up about a week before a new Direct is about to be announced. Earlier today, a blank space opened up on the Directs page (see bottom right of the picture), so word on the street is we should know within a couple of weeks whether or not we're getting a Direct, when it will air, and what it will be about."

This wouldn't exactly be unprecedented- Nintendo hosted a Direct in May 2015, for example, though that was to talk about the imminent release of Splatoon. Edit: Nintendo also hosted two Japan only Directs, and a Direct for Europe/North America, in May 2013.

The website I linked to speculates there might be a Pokemon Stars announcement, but I'd expect Nintendo to save anything that big for E3. We might instead get more announcements that would be lost at E3, like more details on upcoming 3DS games (Fire Emblem, Miitopia, Ever Oasis), more information about New 2DS XL, or perhaps even an update on Virtual Console, the Animal Crossing mobile game, or Nintendo Network/My Nintendo.

Second Edit: In the May 2013 Direct, Nintendo talked about:

• Mario & Sonic at the Olympic Games
• Sonic Lost World
  
• Game Gear on 3DS Virtual Console
• Oracle of Ages/Seasons on 3DS Virtual Console
• Mario vs Donkey Kong: Minis on the Move for 3DS eShop
• DKC: Returns 3D
• Animal Crossing New Leaf Youtube video series/Streetpass plaza update
• Game & Wario update
• Resident Evil Revelations heading to Wii U eShop
• New Super Luigi Bros U update
• Wonderful 101 release date
• Pikmin 3 update
• E3 information (demo tour in the US/Canada)

I would bet for an ARMS direct... Too close to the last "general" Direct to be another one.

Pokémon Stars could be, though, and maybe this is the best moment to announce it (far from other important releases), but I'm not sure about it.

ARMS makes sense. I mean not going to announce a bunch of stuff a month out before E3.

Only that make sense is ARMS focused AND, or maybe Pokemon Stars announcement.

The's a Pokemon event on May 20th called look upon the stars.

Nintendo having a general Direct doesn't mean there's huge news. Skimming through that May 2013 Direct, there wasn't anything big. New Virtual Console announcements, a new Mario & Sonic game, a couple of eShop announcements, and updates on previously announced titles. There's no reason why Nintendo shouldn't give some attention to eShop, Virtual Console and previously announced games in the next week or so, or even announce a smaller new game for Switch. We've also just had a Direct that went into some detail on ARMS, so I don't see that happening again- perhaps a new character announcement.

E3 is going to be Mario Odyssey, Xenoblade 2, Fire Emblem Warriors, Splatoon 2, probably Dragon Quest XI, FIFA 18, Skyrim, plus any Nindies, some new third party announcements (or updates) Nintendo want to feature, plus some new Nintendo titles for late 2017/first half 2018 (so any Mario Maker/Smash port news if real, Pokemon Stars if real, Fire Emblem Switch etc). There'll be a lot to talk about at E3 even if Nintendo decide to make some smaller announcements in the next week or two.

it has to be an ARMS direct.

this game is yet to explode

Hope its not just for ARMS. If it is, then pass.

Same, that is one game I really don't want Nintendo to put too much into, I just can't see it being as big a thing as they want it to be, can always be wrong though, it has happened before :)

Interesting, as long as it's not some 3DS-focused Direct, i'm happy!