Yes, those probably were gray tree frogs.  They can vary considerably in color.

 From: Charlie La Rosa <[log in to unmask]>
To: [log in to unmask] 
Sent: Tuesday, September 3, 2013 9:59 PM
Subject: Re: [VTBIRD] Peeper or tree frog?

At Button Bay State Park we had several small bright green frogs clinging
to window glass at night. Just the other day I had one clinging to the side
of my green canoe. I think young gray tree frogs can be green and, in any
case, they are quite adept at camouflaging themselves. Maybe someone can
comment further.
Charlie La Rosa
Brattleboro, VT

On Tue, Sep 3, 2013 at 12:25 AM, Jane Stein <[log in to unmask]> wrote:

> I just discovered a very small amphibian clinging to my kitchen window.
>  He/she measures a scant 1 inch from butt to tip of nose.  His/her throat
> is vibrating strongly, but I can't hear a thing through two layers of glass
> (and slightly less than perfect hearing). And I can't see his/her coloring
> beyond his underparts, which are sort of ordinarily froggy pale, light
> gray-ish-whitish to greenish-tinged on the edges.
> Could this be a peeper?  It does seem too small for a tree frog, one of
> which I also once discovered clinging to the same window but in early
> summer. Do peepers do this?
> Jane
> (Shoreham)
> On 9/2/2013 8:37 AM, Hilke Breder wrote:
>> I'd like to thank everyone concerned for your input on the mystery
>> sounds!! So the consensus
>> is it's a spring peeper, prompted perhaps by the shortening days; and
>> possibly a young male
>> trying out his voice. Our house is next to a wetland and in the spring
>> the peepers are
>> deafening. (**Spring_Peepers.mp3<>)
>> And yes, Kent, I am going to
>> enter my recordings into the Vermont Atlas of Life
>> **.
>> Hilke Breder
>> Brattleboro