We keep hearing how driverless cars are the wave of the future. These machines have been tested for many years and are supposed to be much safer than vehicles with a human driver. But there is one issue facing these vehicles that is not often talked about: inclement weather.

These robotic cars are supposed to handle all traffic situations with ease. They have radar and sensors to help them identify pedestrians and road hazards. They are smart enough to park themselves. But when it comes to rain, hail, snow and yes, seagulls, the computers in these cars just can’t handle it.

Even human drivers can navigate rain, ice, snow and avian creatures with ease, so what’s the deal with autonomous vehicles? Seems like an embarrassing problem, considering that these cars are made of sophisticated software that is supposed to handle just about everything else in its path.

NuTonomy, which has been road testing autonomous vehicles in Boston, has found that snow and seagulls are a driverless car’s biggest adversaries. Snow affects these cars in two ways. First, it affects the traction, making it harder to drive. It also affects the car’s sensors and how the vehicle views the street.

Seagulls, on the other hand, are a nuisance because they stand in the street, oblivious to the quiet electric engines of the NuTonomy vehicles. This causes the vehicles to stop in the middle of the road. To solve this problem, the cars are now programmed to creep forward to startle the seagulls.

Inclement weather is not an isolated issue. All manufacturers of autonomous vehicles struggle with it. They have focused on software and algorithms, but are at a loss when it comes to the weather. Cameras do not function well in fog and snow and lidar lasers will simply bounce off raindrops and snowflakes. GPS can be slow at times, and the radar cannot always distinguish between obstacles in the road, especially when there is inclement weather.

This may require reprogramming vehicles to use sensor fusion, which involves using the best information and filtering out the rest. Waymo, for example, is using special software so that vehicles can filter out the rain. The company is conducting road tests in more than two dozen cities across the country. They are testing minivans in various weather conditions to see how they perform. However, it could still be a few years before all the bugs are worked out and an autonomous vehicle is able to successfully navigate Boston weather without incident.