Camp Creek Mountain Waves

For Camp Creek Observations, click here

In cooperation with the National Weather Service's Morristown, TN, forecast office (WFO), the Air Resources laboratory's (ARL) Atmospheric Turbulence and Diffusion Division (ATDD), Oak Ridge, TN, installed a meteorological monitoring station at the Camp Creek Elementary School. The Camp Creek school is located approximately 10 miles east of Greenville, TN. The ARL/ATDD weather tower, which has been in operation for several months, is designed to provide forecasting support for strong winds generated from mountain waves which historically have caused significant property damage throughout the Camp Creek region.

Meteorological Monitoring Station

To forecast mountain waves, the Morristown WFO looks for southeast winds that are perpendicular to the mountains of at least 15 knots in the boundary layer (between the surface and 850 mb), a surface-based stable layer extending above the mountains (usually to around 750 mb), and a critical level where the winds become parallel to the mountain ridges (in our case - usually southwest winds around 700 mb). If there is a strong 850 mb jet to the west or northwest of the mountains, the surface winds in the foothills can be enhanced. At Cove Mountain, located on the western side of the Great Smoky Mountains, winds have exceeded 100 mph in many of these cases. Northwest winds can produce mountain waves as well, but on the eastern side of the Great Smoky Mountains. Since the vertical profile of the southern Appalachians is such that the western slopes are steeper than the eastern slopes, theoretically stronger mountain waves should occur on the western side as opposed to the eastern side.

In addition to high winds in the foothills, foehn (adiabatic) warming typically occurs with mountain wave events downwind of the mountains in the valley. These are also known as Chinook winds or Santa Ana winds. A unique feature of foehn winds in our area is that the dewpoint typically rises (in other areas of the world, foehn winds are dry winds). In early observational data, temperatures and relative humidity increased during the time of southeast winds.