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Snowfall Prediction Research
Research project aims to improve WNC snowfall projections
Accurately forecasting snowfall can be a hit or miss proposition in North Carolina's mountains as residents and visitors can attest.
Professors from Appalachian State University, UNC Asheville and N.C. State University hope to change that by collecting a range of data to refine computer models used by weather forecasters to predict snowfall.
The project is funded by an $84,740 grant from the UNC General Administration's Competitive Research Fund.
Baker Perry, an adjunct assistant professor in Appalachian's Department of Geography and Planning, is the lead researcher for the project. He will be assisted by Doug Miller from UNC Asheville and Sandra Yuter from N.C. State University.
The problem with creating accurate forecasts lies in the diverse mountain topography, Perry explained.
"It's very challenging to forecast snowfall because the spatial variability is so pronounced here in the mountains," he said. In Western North Carolina, elevations range from 1,000 to 6,684 feet.
"Computer forecast models don't fully account for the effects of mountain topography," Perry said.
The lack of weather observations and data collection in the mountains is another impediment to developing accurate forecasts, Miller said. "When we talk about an area that covers peaks and valleys, there are a lot of microclimates within a weather event that we can't even observe," he said. "We can't forecast something that we can't observe. That's why the forecast process is so difficult."
Perry, Miller and Yuter have installed weather instruments at the base and top of Poga Mountain in Avery County (pronounced as Pogey Mountain by most residents).
The instrumentation includes a vertically pointing radar to measure the intensity and fall speed of precipitation at different levels of the atmosphere; a laser-equipped instrument that measures particle size and speed; and a gauge that measures liquid of solid precipitation.
"There are essentially no data from this region on snow density, so that's one of the things we are really focusing on," Perry said. Current weather forecasting models tell how much liquid will be generated when snow or frozen precipitation is melted. "It's the forecaster's job to make some assumptions of what the snow-to-liquid ratio will be to come up with a snowfall forecast," he said.
Undergraduate students from each university will assist with the project.
"For undergraduates, there is no better way to understand things then to get your hands dirty and in this case it's to actually be involved in collecting, analyzing and displaying the data," Miller said. "The experience will give them a good overall perspective on what we rely on ultimately to make our weather forecasts and it will give them a great foundation to help them as future weather forecasters or as graduate students."
The project has been endorsed by officials with the National Oceanic and Atmospheric Administration, the State Climate Office of North Carolina, the N.C. Department of Transportation, and area ski slopes and tourist attractions.
"This is a region where terrain influences are complex, radar coverage is rather poor, real time ground reports are relatively sparse and impacts from snowfall are significant for the economy due to tourism," Stephen J. Keighton with the National Weather Service in Blacksburg, Va., wrote in a letter of support.
Economic impacts related to transportation access and accurate snowfall predictions are pretty substantial for northwest North Carolina, said Crae Morton, president of Grandfather Mountain.
"The ability to accurately measure, study and predict precipitation is of great importance. This affects not only the tourism and other industries vital to the region, but, more significantly, the ability for Department of Transportation, business and citizens to forecast and react to potentially dangerous weather."
This text transcript corresponds to the audio from the multimedia presentation located at the top of this page.
Narrator: Northwest North Carolina is known for its varied terrain that ranges from 6,000-foot-mountain peaks to tranquil valleys. But, the geographic diversity that draws visitors to the region also makes it hard to predict the weather.
Narrator: Researchers from Appalachian State University, UNC Asheville and NC State University collaborate on a project to improve snowfall predictions in the higher elevations by improving the weather data available to meteorologists. They have created a weather monitoring station complete with vertically pointing radar to measure the intensity and fall speed of precipitation at different levels of the atmosphere. There also is laser-equipped instrumentation that measures particle size and speed, and a gauge that measures liquid of solid precipitation. But some of the most important data comes from weather balloons released into the atmosphere.
Narrator: Assistant professor Baker Perry...
Baker Perry: This is part of a larger project to really get some research quality observations during snow events out here, particularly these northwest flow events.
Narrator: Perry lives atop Pogey Mountain in Avery County where the weather monitoring station is located.
Narrator: A series of weather balloons released during snow storms collect temperatures, relative humidity, and wind speed and direction at different atmospheric levels. Snow depth and the snow water equivalent are measured at the site.
Narrator: UNCA professor Doug Miller analyzes data collected during the balloon launch...
Doug Miller: We are going to work together to launch a weather balloon. This is not fooling around this is actual data we are going to collect and post.
Doug Miller: This is the payload. The little bead at the top is a temperature sensor, In addition to that we have two antenna in here. The blue one here is the UHF antenna. It sends most of the metrological information like temperature, moisture and pressure. And then the tall part of the sonde is the GPS.
Narrator: When the balloon is released, it can travel as high as 60,000 feet. Weather service offices in Virginia and South Carolina use the data transmitted from the balloons to adjust their forecasts.
Narrator: Data collected at the Avery County site and information gathered by weather watching volunteers across the region are creating more accurate computer models related to snowfall predictions.
Baker Perry: If we can improve the forecast process and the guidance and ultimately improve forecasting for these snow events that will give skiers more head's up of when the prime conditions are going to be and give the DOT more advanced warning to clear the roads and to really allow people to enjoy prime conditions. And that's the thing, particularly these northwest snow events historically they have been very hard to forecast and a lot of times have been under forecast considerably.
Narrator: The research project is supported by a special grant from the UNC General Administration.
Assistant professor Baker Perry observes weather events at the Poga Mountain monitoring station.
Snowfall prediction researchers prepare to launch a weather balloon.
A student assists with inflating of a weather balloon.
A student holds the weather balloon radiosonde.
