The previous record of 68 was set in 1982, lead forecaster David Humphrey said.
Tuesday's high as rain moves out is expected to be around 54 degrees with an overnight low in the lower 30s.
It's the second consecutive Christmas with unusually warm temperatures in Nashville.
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The surface flow will remain out of the southwest to west, with temperatures expected to slowly warm each afternoon until the area reaches into the upper 60s to lower 70s on Wednesday. Maxwell of the National Weather Service said it's too early to predict how cold it might be for parade-watchers spending Sunday night along the route, but it could be 40 degrees or lower.
"We might dry out a bit on that cold front", Stalley said.
Expect a high in the 40s today. There's also a slight chance of showers after noon.
The National Weather Service in Lubbock notes that continued quiet weather is expected Tuesday and Wednesday as the flow aloft starts out southwesterly with a gradual transition to northwesterly on Wednesday.