We're being blinded by the light.

Twice a year, Valley drivers are forced to stare into the rising and setting sun. Just a touch of dirt on the glass, and the view disappears in a wicked glare.

It's a dangerous time, although to what degree cannot be calculated. As AAA Arizona spokeswoman Linda Gorman points out, vehicle crash reports give authorities a check box for causes that include fog, rain and snow - but nothing for sunlight.

This visual impairment happens during the equinoxes, when the Earth's tilt on its axis and its path around the sun combine with the Valley's orderly network of roads, which are aligned to the points of the compass. The autumnal equinox was Monday.

But the aggravation will continue for several days.

At 6:16 a.m. today, the sun rose from nearly due east. And in the minutes before 6:21 p.m., the sun slid slowly toward the western horizon, appearing to drivers like a megawatt light bulb.

Our cars may be making matters worse, according to auto safety experts. The trend toward aerodynamics means vehicles have larger, slanted windshields that reflect more glare from the dashboard.

And those dashboards are lighter in color, heightening the effect.

Use a cleaner on a vinyl dash, and it's now a mirror.

So what's to be done? Beyond the basic safety tips - clean the windshield, drive slower and reduce distractions - traffic safety experts say the only solution is to wait it out.

Mike Branom may be reached at 480-898-6440 or mbranom@evtrib.com.