Spring in Las Vegas is quite warm because the city is in the mid-latitudes. However, in the evening it can be cold, so be prepared with some light clothes.
Sometimes spring can begin already in February and last until mid-May. During this period the temperature is comfortable in Las Vegas and there is no precipitation. Towards the end of May, the air temperature rises rapidly up to + 28°C (82°F). This is the best time to travel to Las Vegas with lots of food festivals and rodeos.