Sorry, I was not referring to the SeaFoam quote, which is conventional usage as I understand it.It was a QUOTE from the SeaFoam site. They were apparently referring to Ten Degrees Fahrenheit.
I was asking if it was pilot speak to use 10-F to mean 10F. That was what I was trying to ask about your use of 10-F (in the following couple sentences I posted in that question):
"Saying 10-F is quite confusing. Do not think I have seen temperatures stated that way anywhere. Below freezing would then be -10-F. Or maybe 10-F- "
Normally 10F and -10F seems to be the convention.
Just a curiosity question, nothing more.