PHOENIX — ADOT has nearly 200 snowplows and 400 certified drivers stationed around the state to address snow and ice. But as Christmas weekend showed—especially on Interstate 40 from Flagstaff west to Ash Fork and on Interstate 17 south of Flagstaff—a snowstorm can be so intense that travel becomes unsafe quickly.

This is why drivers should monitor conditions before leaving and be prepared to delay travel until snowplows can do their work. A few inches of snow fell per hour at the height of last weekend’s storm, causing crashes and slide-offs and resulting in long closures because of the time required to get vehicles cleared and lanes open again.

In addition to watching National Weather Service forecasts for Flagstaff, Williams or any area you are planning to travel, be sure to check az511.gov or call 511 for the latest road conditions. ADOT’s Twitter account (@ArizonaDOT) is a good source of information and interaction.

A 28-car pile up occurred at the 163 exit of I-40 in Williams on Christmas Eve keeping many stuck for up to eight-hours. If you drive faster, you may not get through the snow faster. You may not get through at all. When it rains it can be just as dangerous overnight as the temperature drops and ice builds up on the roadways.

Because snowstorms can result in sudden closures sometimes lasting for hours, ADOT offers tips at azdot.gov/KnowSnow that include packing an emergency kit with blankets, warm clothing, snacks and water and keeping your gas tank half to three-quarters full at all times. It is also good to have a charged cellphone, but some areas do not have cellphone service. A radio transmitter, such as the FRS/GMRS radios, Citizens Band or amateur radio equipment is also a good idea.

But the safest option when snow is falling is not being on road unless it’s absolutely necessary.

During the storm, white cars were observed driving in the snow without lights making them difficult to see. Turn your lights ON during a storm, whether rain or snow, no matter the color of your vehicle if you feel you must drive at all. You need to make yourself as visible as possible.

With another storm forecast for New Year’s weekend, recent experience reinforces the value of waiting until roads are plowed and ready for traffic. If there’s any question about whether it’s a good idea to go, you’d probably do well to wait.

When highways are plowed and ready for traffic, many drivers may be heading uphill to play in the snow. If you’re among them, be sure to leave prepared, as New Year’s usually is an especially busy weekend at snow-play areas, especially along US 180 outside of Flagstaff, resulting in long lines of traffic at day’s end.

Those heading to snow-play sites along US 180 may want to consider making an earlier start home, as on busy days traffic builds toward Flagstaff throughout the afternoon. When they reach Flagstaff, drivers taking Interstate 17 south can save time by following a marked alternate route to Interstate 40 at Butler Avenue, via Switzer Canyon Road and Route 66, and then heading west to I-17. A map of this route, as well as locations of snow-play sites, is available at FlagstaffArizona.org (follow the Winter Snow Play link).