Crosswinds Where the Delta Breeze Funnels Through

The Carquinez Strait is the narrow gap where the combined Sacramento and San Joaquin rivers push through the Coast Range on their way to San Pablo Bay. Air does the same thing. When the Central Valley heats up and pulls marine air inland, the Strait becomes a funnel, and the two interstate bridges crossing it — the Carquinez Bridge carrying I-80 between Crockett and Vallejo, and the Benicia–Martinez Bridge carrying I-680 — sit high and completely exposed in the middle of it.

Afternoons are worse than mornings. Summer is worse than winter. And the wind advisory signs on the approaches are not decoration.

What a crosswind actually does to a vehicle

A steady crosswind is manageable. You lean on the wheel a few degrees and drive. The problem is not steady wind; it is the transition. Bridge structures, sound walls, terrain and other vehicles all create sheltered pockets, and the moment you leave one, the full force of the wind arrives at once. That is the shove that puts a vehicle into the next lane.

How much it matters depends almost entirely on the shape of what you are driving:

• An empty box van, a rental moving truck or a high-sided trailer is a sail. These are the vehicles that get pushed and, occasionally, blown over.
• A pickup towing anything gets the wind acting on the trailer behind the pivot point, which is how sway starts.
• A tall SUV or van notices it. A low sedan mostly does not.

The habits that work

Slow down first, before the exposed section rather than during it, because every one of these effects scales with speed. Hold the wheel with both hands at a normal grip, not a death grip, so you can feel what the car is doing. Move away from high-sided vehicles rather than travel alongside them, because passing a semi in a crosswind means going from its wind shadow into the full gust and back again within a few seconds. And if you are towing and the trailer starts to sway, ease off the throttle and let it settle; steering corrections and braking both tend to make sway worse.

If the wind causes damage

Here is where the coverage question gets genuinely interesting, because wind sits on a line.

If a gust blows debris into your car, or blows something off a truck into your windshield, that is the kind of loss comprehensive coverage is designed for. If a gust pushes you into a barrier or another vehicle, that is an impact, and impacts fall under collision. Same weather, two different coverages and often two different deductibles. Which one applies to a given event is a determination your carrier makes on the facts, and it is worth knowing that both exist and that both are optional coverages you either carry or do not.

The trailer question

People assume a trailer is covered because the truck is. Broadly, liability coverage on the towing vehicle commonly extends to a trailer while it is attached, which addresses harm you cause to others. Physical damage to the trailer itself is a different matter and frequently needs to be scheduled or covered separately, particularly for anything of real value like a boat or a travel trailer.

This varies more between carriers than almost anything else in a personal auto policy, so do not take a general statement as the answer for your policy. If you tow across the Strait regularly, get your own carrier to tell you in writing what is and is not covered on the trailer.

Towing something valuable? Tell us what it is and we will make sure it is actually covered.