Las Vegas hasn't measured rainfall in 160 days. This regional dry spell has resulted in a build up of dirt and grime on roadways. This dirt and grime, when combined with light rain, becomes very slick (because light rain isn't enough to wash it away). On Christmas Eve, there is a 20-40% chance of LIGHT rainfall across the region. Drive safely by slowing down. Stopping distances are 2 times their typical distance on wet roads.