Mother Nature threw a wrench into Alphabet Inc.'s (GOOGL) robotaxi ambitions on Christmas Day. Waymo, the company's autonomous vehicle division, temporarily shut down its San Francisco Bay Area service amid flash flood warnings, reminding everyone that even the smartest self-driving cars still need to play it safe when the weather gets nasty.

When It Rains, It Pauses

The company notified riders through its app on Thursday with a straightforward message: "Service temporarily paused due to National Weather Service flash flood warning," according to a CNBC report. It's a sensible call, though probably not what holiday travelers wanted to see pop up on their phones.

This isn't Waymo's first rodeo with service disruptions in San Francisco. The company previously halted operations when a PG&E Corp (PCG) substation outage knocked out traffic signals across the city. Following that incident, Waymo rolled out fleet-wide software updates designed to help its vehicles handle outages more gracefully. Apparently, building robots that can drive themselves means constantly teaching them how to deal with the messy realities of urban infrastructure.

Tesla's Rain Problem

The timing is interesting because Tesla Inc. (TSLA) CEO Elon Musk just announced that a Tesla robotaxi drove him autonomously around Austin on Saturday. Musk has been promising driverless operations in Austin before year-end, and this demo suggests he's pushing toward that goal.

But here's the kicker: Ross Gerber of Gerber Kawasaki pointed out that Tesla's Full Self-Driving system has been confusing raindrops on cameras for debris, causing the software to struggle in wet conditions. So while Waymo is proactively pausing service during flood warnings, Tesla's system apparently needs to figure out the difference between actual obstacles and water droplets. Weather remains a stubborn challenge for autonomous vehicles across the board.

The Leader Pulls Further Ahead

Despite the occasional weather timeout, Waymo is crushing it in the robotaxi race. The company announced it completed 14 million paid rides in 2025 and recently hit 450,000 weekly rides. Those numbers put Waymo firmly in the driver's seat (so to speak) of the U.S. autonomous vehicle market.

The company's cautious approach to extreme weather might actually be part of why it's winning. Taking your fleet offline during flash flood warnings isn't glamorous, but it beats the alternative of having autonomous vehicles struggling through dangerous conditions or, worse, getting stranded in flooded streets.

Alphabet (GOOGL) demonstrates strong momentum and quality metrics, though value investors might want to look elsewhere. The stock shows favorable price trends across short, medium, and long-term timeframes.

Price Action: GOOGL shares climbed 0.09% to $314.36 in pre-market trading on Friday.