Temperature Range (Product ID):
blank = 0°C to +70°C (Commercial)
I = -40°C to +85°C (Industrial)
E = -40°C to +125°C (Extended)
Document page numbr 209 of your link WA
. I couldn't help my pedanticity, sorry.
But maybe hippy is describing the actual PIC type used for PICAXE? I haven't looked.
Note the important points hippy made in his post. Try to use crystals if using over a wide range.
But there is no substitute for reading the Microchip Data Sheets and checking the chip ident.
If you intend to use it in a cold environement beware (be aware?) of condensation issues.
And also check the temp range of the other components on your board. More Data Sheets to read, sorry.
If using in a hot environment the same applies but also have a care if using other devices that get hot even if using heatsinks. e.g. power transistors.
This may not apply in your current app. but remember it for the future.