Best Practices for Road Weather Management Version 2.0

Title:

Ensemble Member Forecast Spread and Its Implication for Road Weather Forecasting

Abstract:

The FHWA MDSS utilizes state-of-the-art weather forecasting and data fusion techniques and merges them with computerized winter road maintenance rules of practice. The result is a set of guidance aimed at maintenance managers that provides a forecast of surface conditions and treatment recommendations customized for specific routes. Several weather models are used by the Road Weather Forecast System (RWFS), which generates a consensus forecast used within other MDSS components. The overall forecast spread predicted by the ensemble model members of the RWFS, for a moderate snow event on 27-29 November 2004 is presented to illustrate the large differences often found between model members. Several meteorological parameters are examined from several numerical weather prediction models. For a single weather event it is shown that the predictions from each model varied for air temperature, dewpoint temperature, cloud conditions, and precipitation. It is important to be aware of the forecast differences for each weather parameter. The large spread that is evident between all of the models lends credence to the ensemble forecasting approach utilized in the RWFS which results in a final consensus forecast that is often times better than many of the individual models.

Source(s):

American Meteorological Society (AMS) Annual Meeting, NCAR

http://ams.confex.com/ams/pdfpapers/100091.pdf

Date: 2006

Author:

Wolff; Linden; Mahoney, III

Keywords:

Decision support

PDF files can be viewed with the Acrobat® Reader®.