Water suspended in zero gravity would be frozen as ice crystals and would not be boiling, the freezing cold temperatures of space would help keep the water from doing such.
Also, one thing we all know about water is that it is translucent! This canopy could have diffused the light somewhat making the natural light at ground level less intense, which would actually be beneficial. It would also stop heat from escaping through the atmosphere thereby keeping the earth's temperature a consistent moderate-warm.
Clearly in Genesis 2:5, it did not rain at all at one stage of the Earth's creation - but rather it was watered from underground reservoirs of water which 'came up out of the ground'. Genesis 2:5 - "And every plant of the field before it was in the earth and every herb of the field before it grew - for the LORD God had not caused it to rain upon the earth, and there was not a man to till the ground. (6) Instead, springs came up from the ground and watered all the land."
Many claim that this is not evidence of it still not raining in Noah's time and that is very true, but the verse in Genesis 9:13 attests that it still did not rain right up until the time of the flood.
Genesis 9:13 - "I have set my rainbow in the clouds and it will be the sign of the covenant between me and the earth. (14) Whenever I bring clouds over the earth and the rainbow appears in the clouds, (15) I will remember my covenant that is between me and you."
Obviously for a rainbow to appear, there needs to be clouds of water in the sky which means that during Noah's time - there were no clouds in the sky!
No rainbows occurred because all the water above the earth was suspended well above the sky/atmosphere itself.
Also we are told in Hebrews 11:7 - "But by faith, when Noah was warned about things that had never been seen, he built an Ark to save his family."
Clearly things like rain and storms and such had not been seen whatsoever in Noah's time. The Bible clearly tells us about 'floodwaters in the heavens' (Genesis 7:11) that were there in Noah's time and that they 'opened' and the water came down causing the flood to happen. NO amount of clouds could drop enough water to flood the whole earth nor come anywhere close.
Peter also mentions: (2 Peter3:5) "God made the heavens by the word of his command and he brought the earth out from the water and surrounded it with water.