Utah is known for its dry heat. But this past August deviated from the norm.
The dew point for the entire month of August was nearly double the normal levels for Utah, according to data from the National Weather Service obtained by KUER.
The drier the air, the lower the dew point. More moisture pushes the dew point higher. According to the National Weather Service a dew point over 65 degrees will be muggy and uncomfortable.
And for the first time in documented history, the Salt Lake City airport reached a record high dew point of 72 degrees.
“It's very rare,” said Alex DeSmet, a meteorologist with the National Weather Service.
“In fact, before the summer, we'd only seen the dew point get to 70 at Salt Lake Airport less than five times.”
Two weather events caused the surge in humidity. First, DeSmet said “an unusual disturbance” occurred when Gulf of Mexico and Gulf of California weather patterns merged together and moved through Utah in early August.
“That's when we saw the Draper flooding. That's when we saw the flooding in Corinne, Brigham City [and] Willard,” he said.
The second reason was the remnants of Hurricane Hilary pushing its way up the West Coast toward Los Angeles and San Diego.
While severe and unusual weather events such as Hurricane Hilary played a role in the increased humidity levels, Dr. Peter Howe, a climate scientist at Utah State University, said people should anticipate more humid summers moving forward.
“We are likely to see more humidity continue into the future. So next year may not be quite as humid as this year, but on average, going forward, we're likely to see more humidity than we have in the past few decades,” Howe said.
That’s because, he said, the climate is changing and it’s getting warmer globally. Humidity is how much moisture is in the air, and warm air holds more moisture. Since it’s getting hotter around the world, areas that aren’t normally humid, like Utah, are hanging onto condensation from wet weather patterns, causing more humidity.
And events like Hurricane Hilary aren’t expected to be incredibly rare anymore. Howe said severe weather, like hurricanes and cyclones, are predicted to occur more often, and Utah won’t be immune from the impacts, despite being a landlocked state.
Additionally, Howe said Utah is experiencing more humidity in urban areas of the state due to heat islands.
“The structures that we build, parking lots and roofs, these things all hold a lot of heat through the night” he said.
“And that causes our nighttime low temperatures to be higher in cities than in the surrounding area. And we definitely see that in Salt Lake City.”
DeSmet added it’s harder to cool off the body with humidity in the air. He said the human body sweats to bring down the internal temperature, but in cases of high humidity the body has a harder time doing so.
“It's great for plants, but it's not so great for humans and pets where our bodies stay cool by evaporation from sweat,” DeSmet said.
Howe emphasized that Utah will most likely never reach the humidity levels felt in the South, like in Alabama and Florida. But Utahns will have to alter their behavior to adapt to a changing weather landscape. He said swamp coolers won’t work as well, and it’s advised to switch to central air conditioning or invest in a window unit.
“I would recommend folks to keep an eye on when there's a heat advisory. That means that you need to pay attention and potentially change your routine and prepare for the heat.”
