Window air conditioner drips some water on the grille?

hi I just noticed last night that my window air conditioner drips some water on the inside grill at the top of the air conditioner. I put it in over a month ago and this is the first instance of this occuring. I'm not referring to the natural drip that occurs outside the window as a result of condensation, that is normal. I'm referring to the part of the air conditioner inside the room (the front of it). it's only a few drops, but i noticed this as strange. it's the first time its ever happened (i bought it 2 years ago). It got very humid and rainy last night, so that seems to have triggered it. does anyone know what this could be? any help would be much appreciated! Thanks