Solar kiln temperatures in the fall/winter

[Stevenjohn21]

I am still in the organizing stages of owning a sawmill so I realize the timing to make a solar kiln is a little late but I want to make sure it’s ready for it’s first batch come late spring/summer next year. 
So my question is, what temperature should I be seeing in the solar kiln in the next month? I’m in the Atlanta, Georgia area where temps are around 75 degrees right now but by the time the kiln will be built it’ll probably be in the 60’s. 
If I’m aiming to get around 135-140 degrees in the summer when it’s 90 degrees outside should I expect 105-110 degrees when it’s 60 degrees outside?

[doc henderson]

a lot depends on your build.  any temp above ambient will drop the RH and still work, but take a little longer.  great for oak ect.  seal it up well, insulate well.  I find with solar kilns, myself included, I tend to get a mind warp thinking I have the next great solar kiln idea.  Mostly about making it cheaper or better somehow.  they are simple and should be kept that way.  Dr. Wengert once told me "It is just a solar kiln".  If it is 30° out and the kiln is 50° or 60° it will work.  just not as fast, and will not kill bugs.  After sealing and insulating, you can talk glaze angles and direction to face, but only tiny returns in efficiency.

[YellowHammer]

As Doc says, anytime the temp in the kiln is warmer than ambient, the air can carry more water so the kiln is working.

I built mine in the dead of winter in Alabama, and one day when it was snowing, I was inside it with a short sleeve shirt.

In actuality, the best time of the year to build one is in the winter or it will be too hot inside.  

[scsmith42]

In my spray foam insulated, dual pane polycarbonate solar kilns I will see up to a 55 degree temp increase over ambient year round.

The amount of rise is influenced by the rate of mc release from the lumber too.

[Larry]

So my question is, what temperature should I be seeing in the solar kiln in the next month?

If I understand your post correctly next month your kiln will be complete but empty until the spring.  The temperature of a empty kiln will be much cooler than one filled with wood.  The wood load heats up slowly over a few days than will carry the heat through the night.

[doc henderson]

Larry, I believe, an empty kiln can overheat and melt the plastic fan blades.  

[caveman]

Our polycarbonate roof panels are old and need to be cleaned but when new, on sunny days it would generally heat up to about 50 degrees above outside temp.  We are at 28°N and built the roof at 30° and it faces south.  Yesterday afternoon it was in the mid 80's here and the inside of the loaded kiln was 125°.  We built ours without vents but leave the doors slightly ajar and open them for a few minutes each day to dump moisture.  Even with the doors tightly closed, there are enough air leaks to release moisture.  I don't know if this is the right way to do it, but it seems to work well.