Boulder Foothills Face Dangerous Downslope Winds Wednesday. Patio furniture may become airborne and visit your neighbors. Shingles may fly. Here’s generally what we know. 

When the Mountains Exhale: A Front Range Wind Story:

There are days on the Colorado Front Range when the mountains seem to breathe out. Well, more like full blown sneezes. You feel it first as a whisper. Then a shove. Then a sustained push that rattles windows, bends trees, and reminds everyone along the foothills and plains that we live at the edge of something powerful.

Wednesday is shaping up to be one of those days.

This is not an everyday breeze. This is a classic Front Range downslope wind event, the kind locals remember by what blew over, what lost power, or what sounded different in the trees. Here’s what Lafayette might feel like and experience on Wednesday, hour by hour.

Lafayette Focus on Expected Wind Event

How  these wind events work:

Strong winds aloft cross the Continental Divide from west to east. When conditions line up just right, that air accelerates downhill, compresses, and pours out of the foothills like water through a narrowing canyon. Meteorologists call it downslope flow. Meteorologists call this downslope technically a katabatic flow.   Longtime Front Range residents call it a day to tie everything down and to strap on your hats. The result is a sharp ramp-up in wind late morning, peak gusts in the afternoon, and a slow taper into the evening. Calm mornings can give a false sense of security. By midday, things change quickly.

In communities like Lafayette, Louisville, Boulder, and Longmont, Wednesday’s wind story is expected to unfold like this: Morning hours remain relatively quiet, with light winds that feel ordinary for December. Late morning brings the turn. Winds strengthen rapidly, shifting westerly and becoming gusty.

Early to mid afternoon is the danger window. Gusts peak, travel becomes tiring, and loose objects become airborne candidates.

Evening sees a gradual decrease, but not an immediate calm. Strong gusts can persist well after sunset. The chart above shows that familiar Front Range curve. Low early, steep climb, high plateau, then a long slide down.

Where the strongest winds are likely

Not all places experience these winds equally. Terrain matters. Elevation matters. Canyon shape matters.

Expected Wind Speeds

Highest gusts are expected in the foothills as normal during a wind event. 

The strongest winds are expected in the Boulder and northern Front Range foothills, especially along steep east facing slopes and canyon mouths. Places like the Peak to Peak Highway corridor, Nederland, Jamestown, Tolland, Rollins Pass, Coal Creek Canyon, and Crisman are well known wind amplifiers. In these locations, gusts of 80 to 90 miles per hour are possible, and in the most extreme, channeled spots, brief gusts over 100 miles per hour cannot be ruled out. These are the areas where trees fall, roofs lose shingles, and power lines are most vulnerable.

Hills and mesas above Boulder: Moving downslope but still elevated, areas such as NCAR Mesa, Table Mesa, Bear Canyon, and Boulder’s hillside neighborhoods often see powerful but slightly less extreme winds. Gusts here commonly range from 70 to 85 miles per hour during strong events.

These winds are more than enough to cause damage and outages, especially where trees and older infrastructure are involved.

The plains and urban corridor

Out on the flatter terrain, from Fort Collins through Lafayette, Longmont, Denver, and Aurora, winds usually ease compared to the foothills but remain impactful. Gusts in the 50 to 70 mile per hour range are likely, strong enough to make driving difficult, knock down branches, and cause sporadic power disruptions.

Why this matters: High winds are not just a weather curiosity. They affect real lives. Power outages become more likely. Travel, especially for high profile vehicles, can become hazardous. Fire danger increases dramatically when strong winds combine with dry fuels, even in winter. Outdoor plans often need to be reconsidered.

A Front Range reality check

If you have lived here long enough, you know these days. The ones where the wind sounds different. Where the house creaks a little. Where you instinctively check that the trash cans are secure and the patio furniture is not about to visit your neighbor. Wednesday looks like one of those days.

It is not a reason for panic, but it is a reason for awareness. Secure loose items early. Plan travel carefully during the afternoon hours. And if the wind starts howling, remember that this is the Front Range doing what it has always done.

Sometimes, the mountains exhale.

Shared Knowledge Is Power!

Lenny “Lensworth” Frieling

Lenny Frieling Pen Of Justice

• Multi-published and widely syndicated blogger and author.
• Most recently published by Amazon, his first book, "Lensworth"a book of his prize-winning photos.
• University lectures at University. of Colorado, Boulder, Denver University Law School, Univ. of New Mexico, Las Vegas NM, and many other schools at all levels. Numerous lectures for the NORML Legal Committee
• Former Judge
• Media work, including starring in episodes of Fox’s Power of Attorney, well in excess of many hundreds media interviews, appearances, articles, and podcasts, including co-hosting Time For Hemp for two years.
• Life Member, NORML Legal Committee, Distinguished Counsel Circle.
• Photographer of the Year, AboutBoulder 2023
• First Chair and Originator of the Colorado Bar Association’s Cannabis Law Committee, a National first.
• Previous Chair, Boulder Criminal Defense Bar (8 years)
• Twice chair Executive Counsel, Colorado Bar Association Criminal Law Section
• Life Member, Colorado Criminal Defense Bar
• Board Member Emeritus, Colorado NORML, and prior chair during legalization, as well as pre and post legalization
• Chair, Colorado NORML, 7 years including during the successful effort to legalize recreational pot in Colorado
• Senior Counsel Emeritus to the Boulder Law firm Dolan + Zimmerman LLP : (720)-610-0951
• Board member, Author, and Editor for Criminal Law Articles for the Colorado Lawyer, primary publication of the Colorado Bar Assoc. 7 Years, in addition to having 2 Colorado Lawyer cover photos, and numerous articles for the Colorado Lawyer monthly publication.
• http://www.Lfrieling.com