Extended Abstract (76K)P2.16
Regional scale modeling for the 2002 Olympic Winter Games
Daryl J. Onton, NOAA/CIRP and Univ. of Utah, Salt Lake City, UT; and A. J. Siffert, L. Chang, W. J. Steenburgh, and B. Haymore
In February 2002, the Olympic Winter Games will be held in the Salt Lake City Metropolitan area and the nearby Wasatch Mountains. With over 100,000 spectators and athletes attending and competing daily at various venues, accurate weather forecasts are critical for public safety and games logistics. An MM5-based mesoscale modeling system run at 4-km resolution, known as the Intermountain Weather Forecast System (IMWFS), will be a key component of the forecasting system implemented for the games.
The IMWFS is run twice daily on 14 1.3 Ghz AMD Athlon processors of the University of Utah Center for High Performance Computing Beowulf-class cluster. A "mini-ensemble" is completed twice daily, using initial and lateral boundary conditions alternately from the NCEP Eta model and the NCEP Aviation model. Observations from over 2300 surface stations of the MesoWest Cooperative Mesonets, which are assimilated using a version of the ARPS Data Assimilation System (ADAS) modified for use in the complex terrain of the Intermountain West, improve upon the near-surface analysis. The Great Salt Lake temperature is incorporated from AVHRR-derived lake-temperature analyses to more accurately predict lake-effect snows and local wind circulations driven by the lake. After a 66 min integration time required to complete a 36 h forecast, native-grid hourly output from the model is ingested by the National Weather Service's AWIPS system and used by meteorologists at the Salt Lake City, Elko, and Pocatello forecast offices. Model forecasts are also available to the public via the Internet and will be accessed by the 2002 Winter Olympics Venue Forecast Team using a software package called FX-NET.
Despite the relatively small grid spacing of the modeling system (4-km), many aspects of the fine-scale topography surrounding various Olympic venues and transportation corridors remain unresolved. As a result, raw model time series feature large temperature, moisture, and wind biases that reduce their utility for operational forecasting. MOS-type equations have been developed to provide more accurate point-specific forecasts of wind, temperature, dewpoint, and relative humidity at the Olympic Venues and other locations. MM5 MOS exhibits skill that is comparable to that of NGM MOS at Salt Lake City, and has lower errors at many other sites not forecast by NGM MOS.
This poster will highlight the performance of the modeling system and its impact on Olympic games weather forecasting.
Supplementary URL: http://www.met.utah.edu/jimsteen/mm5
Poster Session 2, Orographic Precipitation/Operational and Numerical Weather Prediction (with Coffee Break)
Wednesday, 19 June 2002, 9:15 AM-11:00 AM
Previous paper Next paper