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If you have been following this process you might have read that a warm pocket of air recently influenced the vortex around the north pole. These warm air pockets can cause the vortex to move or split and deliver prolonged periods of cold air and harsh weather to other parts of the globe. However, at times these vortices become unstable during the winter months when warm pockets of air suddenly shift the vortex away from its usual location. The vortex is a low-pressure system that swirls cold air around the polar regions, approximately 18 miles above the planet.
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As the start of 2021 brings hope of a better year, it appears that Mother Nature’s weather pattern may still require us to stay on alert.Īs some may know, polar vortices exist at the north and south poles and generally remain stable and unnoticed. What Can Happen Next?Ģ020 has impacted all our lives enough, so we will keep this next part short as we only mention this in the spirit of being prepared. Water that overflows the dam also creates icicles along the eave. The damage is most severe in areas with frequent freeze‐thaw cycles. This ponded water backs up and flows under the dry laps in the shingles and underlayment, resulting in interior leakage and subsequent damage. As this process continues, the ice height increases, creating a dam that impedes melt water from draining off the roof surface. When it reaches cold, un‐insulated overhangs, it freezes and forms a layer of ice. The melt water will run down the roof toward the eaves and gutters. Heat from the underlying conditioned space, ambient heat, and solar radiation can contribute to melting the snow above the roof surface. So, what is an ice dam on roofs and how/why does it form? Accumulated snow on roofs can actually act as an insulation layer. Even the roof system and deck components.With ice damming comes an increased risk of interior moisture infiltration that can cause damage of: In most cases, if you are experiencing one or the other then you may have an ice dam. Many of us have seen or experienced some form of an ice dam on roofs in our past and is usually evident in the form of large icicles or blocks of ice formed along the eaves of roofs. What Are Ice Dams on Roofs and How Do They Form? But as with many of Mother Nature’s gifts, winter weather brings challenges to our buildings. We love winter for its beauty after freshly fallen snow and for the outside activities we can experience in the mountains or in our own backyards. Many of us who live in the northern states enjoy the change in seasons.