How a precipitation ‘doughnut hole’ makes #Pueblo drier and warmer than most of #Colorado — The Pueblo Chieftain

A satellite image captured on January 20, 2023 from the National Weather Service Pueblo office shows the ‘doughnut hole’ a section of terrain in and south of Pueblo that receives less precipitation than surrounding areas. The white area in the image indicates snowfall and cloud cover. Courtesy National Weather Service Pueblo Office

Click the link to read the article on The Pueblo Chieftain website (Josue Perez). Here’s an excerpt:

A recent satellite image showing snow throughout Colorado offered a glimpse and insight into a novel southern Colorado weather phenomenon: the Pueblo Precipitation Doughnut Hole.  sThe image, released by the National Weather Service of Pueblo, showed that most of Colorado received snowfall on Jan. 20, with some cloud cover mixed in. But there was one specific area that missed out on the precipitation, which encompassed portions of east and northern Pueblo County, as well as portions of Cañon City and some of Colorado Springs.

Fisher peak a spur of the Mesa de Maya (Raton Mesa), Colorado. It rises nearly 4,000 feet (1,200 m) above the town (Trinidad?) in the foreground. By Unknown author – Popular Science Monthly Volume 74, Public Domain, https://commons.wikimedia.org/w/index.php?curid=18486163

That area is the home of the Pueblo Precipitation Doughnut Hole, a cross-section of terrain from south to north that tends to receive less precipitation than the areas surrounding it because of different geographical features such as Raton Mesa, the Arkansas River Valley, Palmer Divide and the surrounding mountains. 

“It’s all about terrain, elevation and elevation change,” said Michael Garberoglio, an NWS meteorologist. “If you’re moving towards Pueblo from any direction, you’re decreasing in elevation, and when air flows down, terrain tends to dry out.” 

Precipitation isn’t a fan of that sinking air flow, so those downslope winds contribute to dry and warmer climates for the region, Garberoglio said. It’s something that’s much more common during winter, especially when dealing with snowfall…

This image illustrates a south to north cross section of terrain and Pueblo’s position in the ‘doughnut hole’. A few terrain features — Raton Mesa and Palmer Divide — contribute to downslope winds that make the area at the bottom of the slope drier and warmer. Courtesy National Weather Service Pueblo Office

Although westerly winds are frequent in the region, intense, low-pressure easterly winds upslope along the terrain, enhancing the possibility for some precipitation, Garberoglio said, as long as they’re strong enough and have enough moisture in them. 

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