Even on the best days, motorists who use Hwy. 100 in St. Louis Park for the morning or afternoon rush hour know it can be a bear of a commute. In about two months, things will go from bad to worse.

That's when the Minnesota Department of Transportation will get back to work on removing one of the most vexing bottlenecks in the metro area. Last fall, the agency embarked on a major makeover of the highway from just south of I-394 to 36th Street. When completed in 2016, traffic should flow much more smoothly, with three lanes in each direction and on and off ramps that are easier and safer to navigate.

The upgrades will come with a steep price: $60 million for MnDOT and two construction seasons of massive backups that will make traveling through the 2-mile area exponentially longer for the 132,000 commuters who use the highway each day.

"I'm not here to scare you, but this is what it's going to be like during construction," MnDOT spokeswoman Bobbie Dahlke told a packed room at a community forum held last week at AAA Minneapolis to prepare residents for what's to come. "If it takes you 20 minutes now, times that by six."

Wednesday's forum was held to educate people with a stake in the impending travel headaches and give them time to plan alternative routes.

This year, the Minnetonka Boulevard overpass will be shut down from April to October, and ramps to and from Hwy. 100 at Minnetonka will be closed. Traffic on Hwy. 100 will be squeezed down from three lanes to two in each direction. And unlike now, there won't be a concrete barrier to separate northbound and southbound traffic.

With the Minnetonka Boulevard bridge out of commission for six months, local streets such as Lake Street, Beltline Boulevard and Wooddale Avenue will see an influx of traffic. The official detour will reroute vehicles and several Metro Transit buses to those streets and Hwy. 7.

Farther to the south, MnDOT may also resurface a section of Hwy. 100 in Edina. That project is pending.

West metro commuters who don't live in St. Louis Park or use Hwy. 100 won't be left unscathed. MnDOT has three other high-profile projects on the docket.

In Plymouth and Maple Grove, MnDOT is adding a third lane this summer on I-494 from Hwy. 55 to I-94. That project will reduce traffic to two northbound lanes in the evening and one in each direction at other times of the day. Combined with the Hwy. 100 work, that will leave Hwy. 169 as the only north-south artery in the west metro with its full complement of lanes.

That's not all. A resurfacing project on I-394 will bring two-week closures of all eastbound lanes between Hwy. 100 and downtown Minneapolis in June and the westbound lanes in July. When lanes are closed, affected traffic will share the reversible HOT lane with buses, motorcycles and carpools. No transit advantage there, so look for a crowded Hwy. 55.

The trifecta came about because funds for I-494 and I-394 became available this year. And the bridges at Minnetonka Boulevard and Hwy. 7 are so dilapidated that the Federal Highway Administration ordered MnDOT to replace them by 2018. Hwy. 7's will be replaced next year.

"It's going to be a mess," summarized Rick Boyd, who has lived in the area for 46 years.