All Donegal maintenance routes across the county are to be gritted on Thursday morning.
Donegal County Council will send out its fleet of gritters from 6am as temperatures are set to plunge.
Sleet, hail and snow are forecast on Thursday and Friday by Met Eireann.
The following are the routes to be gritted:
01: National Primary North
02: National Primary Central
03: National Primary South
04: Inishowen South
05: Inishowen East
06: Inishowen West
07: Milford South
08: Milford North
09: Cill Ulta East
10: Cill Ulta West
11: Na Rosa
12: Binswilly
13: Stranorlar North
14: Stranorlar East
15: Stranorlar West
16: Donegal West
17: Donegal North
18: Donegal South
19: Donegal National Secondary
BT: Buncrana Town
LT: Letterkenny Town