How cold does Las Vegas actually get (and what's at risk)
The dismissive line you hear about Las Vegas winters is 'it never really freezes.' The data says otherwise. The Las Vegas Valley typically records 20 to 30 nights per winter with overnight lows at or below 32°F. Higher elevation neighborhoods (Mountains Edge, Summerlin's western edge, Boulder City, parts of Henderson up against the McCullough Range) routinely run 3 to 5 degrees colder than McCarran's official temperature, which means 30 to 40 freezing nights per year and occasional dips into the low 20s. The valley does not get the prolonged, multi-day deep freezes that Reno or Denver get. What it does get is the more dangerous pattern: warm afternoons in the 50s and 60s followed by sudden overnight drops into the 20s. Pipes that were perfectly fine at 4 PM can freeze and burst by 4 AM. The thaw the next morning is when the damage shows up. Frozen ice expanded inside the copper, split the pipe wall, and the moment temperatures rise above freezing the water pours into a wall cavity or attic. The components most at risk in a Vegas freeze: exterior hose bibs (especially the cheap chrome-plated ones that come standard on tract homes), garden hoses left connected to those bibs over winter, exposed copper or PEX in unconditioned attics, water heater drain pans and pressure relief discharge lines that drain outside, irrigation backflow preventers, pool equipment plumbing, and the refrigerant linesets on outdoor HVAC condensers. The HVAC condenser itself is built to live outdoors and is fine in freezing weather. What can fail is the foam insulation on the suction line. When UV degrades it, the insulation cracks off and the bare copper line can freeze condensation onto itself during a cold snap, reducing efficiency.