SolGuard

See the glare before it sees you.

Driver's view

Your windshield. Red is where the sun blinds.

Drag the edges and the visor line. Make it your car.

Facing --

Glare sensitivity: Standard

Glare, left

Glare, right

Visor line

Must last

When

17:00

Where to?

Or try one.

Pick a start and a destination. Or tap the map. Or try an example.

For Caltrans, counties and cities

Every highway.
Every low sun.

Where glare hits California's state highways. When. And how many drivers it reaches.

Map display

Show traffic

Thicker line, busier road. Caltrans counts.

The day, in glare.

Real weather

Glare, 3+ min Brief glare Marginal Cloud Busier road ➤ Facing the sun

Loading highways...

A year of glare. One file.

Ranked. Mapped. Ready to plan with.

Every ~1-mile stretch, both directions. Ranked by glare VMT: miles driven into a low sun, weighted by how blinding. Traffic, hours by month and time of day, fatal crashes. All in.

How it works

Glare VMT = vehicles passing while the stretch is in glare × its length: the unit agencies already count in, fair to short and long stretches, and it adds up by county or route. The ranking weights it by severity (sun dead ahead in the middle of the glare band = 1). Hotspot = top 5% of all California stretches. Ranks are statewide, also in a county file.
Model: the Standard setting (sun within 12° of straight ahead, 0–18° up, the one checked against crash records), not the sliders; hills included; clear sky (cloud only lowers these numbers); every day, every 5 minutes through the morning and evening low-sun windows. Traffic: Caltrans counts × a typical hourly pattern. Crashes: NHTSA FARS fatal crashes 2015–2024, glare as coded by the investigator, and those that happened while this model says the stretch was in glare. Times are Pacific local time. The sun's yearly path repeats almost exactly, so 2027 serves any year.

Tap a highway.

Tap any highway to see its glare right now.

Watch this drive plays it in the Drive tab. The most blinding stretches live in .

Sun elev

--°

Sun azim

--°

Heading

--°

Δ to sun

--°

Obstruction

Speed

--mph

Needs GPS, a compass and HTTPS. At a desk? Plan a route and tap Watch this drive.

Use two fingers to move the map

time--

sun elevation--

sun vs heading--

cloud--

progress--

drag the slider, or the blue car on the map

glare so far--

clear marginal glare

The sun.
Out of your eyes.

Layers

Glare sensitivity