An hour and a half NE on the interstate is St. George, very nice town, lots of road bike options. Weather should be similar to LV, 60’s - 70’s daytime, low 30’s at night, but it warms up quick. Also consider a trip to the south rim Grand Canyon. Slow time of year, they might have snow, but you can decide after you get to LV. Worth seeing if you’ve never been there and a bike is a good way to get around. It’s the slow season, so fewer idiots in cars. It’s I think 16 RT if you go west from GC Village, 44 RT if you go east, so 2 decent road rides.

Note that some areas in the SW see snow, especially above 5,000 ft in elevation.