Boulder has an ideal climate and geography for the formation of Virga.

Virga is a captivating weather phenomenon in Boulder and elsewhere, that presents itself as streaks or wisps descending from a cloud but evaporates or sublimates before reaching the ground. This meteorological marvel occurs when precipitation falls from a cloud into a layer of air with significantly lower humidity, causing the droplets or ice crystals to evaporate or sublime into water vapor. Virga is not just a beautiful spectacle in the sky; it also offers insights into the atmospheric conditions of an area, such as air humidity and temperature gradients.

In Boulder, Colorado, nestled against the majestic Rocky Mountains, virga is a common sight, especially during the warmer months. The city’s unique geographic location plays a crucial role in the occurrence of this phenomenon. Boulder sits at an elevation where varying air layers with different temperatures and humidity levels are more pronounced due to the surrounding mountainous terrain. As a result, precipitation can start its journey to the earth from a moisture-rich cloud, only to encounter dry air masses that lead to the formation of virga.

Virga Blocking the Flatirons From View. The Rain Is Evaporating or Sublimating Before Hitting the Ground

Virga in Boulder not only adds to the picturesque landscape, enhancing the backdrop of the city against the Rocky Mountains but also influences local weather patterns. For instance, virga can cool the air below it through the process of evaporative cooling, leading to sudden changes in temperature and wind patterns. This cooling effect can sometimes fuel the development of microbursts, which are sudden, powerful airflows that hit the ground and spread outwards.

Moreover, virga embodies the complex and dynamic nature of weather in Boulder and similar regions. It signifies the delicate balance between moisture in the air and the dry conditions of the land below. For weather enthusiasts and the general public alike, virga is a reminder of nature’s intricacies and the beauty that can be found in atmospheric phenomena. Observing virga over Boulder’s landscapes offers a moment of reflection on the marvels of our atmosphere, making it a phenomenon worth appreciating and understanding.

In the top picture, notice the water tower on the left, and then the two white buildings in front of it. The water tower in the second picture is obscured by the virga, and the white buildings are still visible. The Flatirons remain shrouded by a virga curtain.

The Virga in the Sky Is Evaporating or Sublimating Before Hitting The Ground, and our Buff stays dry.

“Evaporate” means going from a liquid to a gas, like water drying up on cement in the sun. Right to water vapor. Sublimation skips that stop. Sublimation is when something goes directly from solid to gas. For example, moth balls, classic paradicholobenzene in case you wondered, goes from white pellets or solid blocks directly into a gas, skipping the liquid phase completely. That is just what Virga does, in addition to normal evaporation.

Lenny Lensworth Frieling

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Leonard Frieling
  • Senior Counsel Emeritus to the Boulder Law firm Dolan + Zimmerman LLP : (720)-610-0951
  • Former Judge
  • 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
  • NORML Distinguished Counsel Circle
  • Life Member, NORML Legal Committee
  • Life Member, Colorado Criminal Defense Bar
  • Board Member Emeritus, Colorado NORML
  • Chair, Colorado NORML, 7 years including during the successful effort to legalize recreational pot in Colorado
  • Media work, including 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.
  • 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.
  • LEAP Speaker, multi-published author, University lectures Univ. of Colorado, Boulder, Denver University Law School, Univ. of New Mexico, Las Vegas NM, and many other schools at all levels.
  • http://www.Lfrieling.com
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