I've not heard of a quoted price changing due to snow, but I talked to an end user who showed me they were invoiced about 20% more than their initial quote due to snowfall.
As it happens, they were initially quoted a cable trenching job during early fall/autumn, signed the quote, but didn't actually get the proper clearance/permissions until there was snow on the ground (image is just for illustration):
**** *** ******* *******, ** *** 20% **** **** *** ******* *****. The ****** **** *** ********* ******* the ******* **-*** ***** *********, ** it *** **** ****** *** **********'* leeway ** ****** *** *****, ***** they ***.
**** *** ***-**** ***** *** **** a ***** ********, *** ********** ********* the ******** ********* *** ****** ** labor ****** (**** *******) *** *** number ** ****** ******* ****** ** finish *** **** *** ** **** worker ********* ** ****** *******.
* *** ***** *** *******/****** **** is *** ***********. ** *** ****** more *** ****** ****?
**** ****’* ****** **** *** ****** work, **** ******* **** ******* **** had ** ** **** **** *** to **** **********, ***** ******** ** be ****** ** *******.