Yes, it will depend on temperature.
The rule of thumb I gave above is a good guideline: 4% for every 10 degrees. Since 4% of 27' happens to be nearly exactly 1', that means it will vary by about 1' per 10 degrees.
That's only a guideline, though. I'm sure I've seen someone post a link to a website that had a formula, and I think the formula took several pages of A4 - I wouldn't ask too many question because you might not like the answers!!!
FFF
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[Edit: Mods, why did this get moved to Private Flying? If it should have been moved from Questions, I'd have thought Tech Log would be the best forum for it???]