The National Weather Service posted a freeze warning from 1 a.m. to 8 a.m. Thursday for southern Erie County and Chautauqua County.
Temperatures are forecast to drop into the low 30s and below-freezing for locations away from Lake Erie and "will kill sensitive vegetation" if it's left outdoors, the weather service said.
"If you are in the warned area, you should protect tender vegetation," the weather service said. "Also, potted plants normally left outdoors should be covered or brought inside away from the cold."
Southern Erie County is generally regarded as any areas south of Route 20A.
A trough of cold air will bring the chilliest temperatures of the season to Western New York tonight and might even result in some scattered snowflakes and lake-effect snow, especially east of the Niagara Frontier.
"Lake-effect showers will continue southeast of the lakes," the weather service said this afternoon. "With the dropping temperatures, rain showers will likely transition to snow showers by dawn on Thursday and some areas may see the first flakes of the season tonight."
Only a dusting of snow is expected in the higher elevation areas where the snow is forecast to fall.
Thursday will stay below normal. Mostly sunny conditions are expected in Buffalo with daytime highs in the mid 40s.
The average high temperature in Buffalo this time of year is in the mid to upper 50s.