Many Old Timers have weather predictions in the Appalachians. Some use the wooly warms, others use old sayings such as "Rain before 7, it will quit before 11(AM)". However most will agree that the Rhododendron is the most reliable indicator for freezing temperatures.
Above freezing, Rhododendron leaves are up and lively.
Around freezing they droop and begin to curl.
In the 20's their leaves have a tighter curl.
As you get close to 0 the tight curled leaves look blue.
As winter draws near, have fun sharing your winter predicting skills with your friends!