Using the Bering Sea and Typhoon Rules to Generate Long-Range Forecasts

Weather forecasting in the short range and long range has improved dramatically over the years (Anderson et al. 1999; Barnston et al. 2005; Lupo and Market, 2002, 2003). Weather forecasts in the short range are routinely issued for as long as seven to ten days. Long range forecasts are routinely issued at least one month to more than a year in advance. Short range forecasting is an initial value problem, which is performed within the framework of the primitive equations, whether these are made observationally, or with the aid of numerical models. Long range forecasting relies on a variety of methods, but are generally constructed using statistical methods, and is considered a boundary value problem. The methods used can be persistence, model of the day, contingency, analogues, or using more sophisticated statistical methodologies. There are medium range products available through the cooperation between the National Weather Service (NWS) regional and local offices and the Climate Prediction Center (CPC) in the range of 8 – 14 days (http://www.cpc.ncep.noaa.gov/products/predictions/814day/interactive/index.php). However, there are few products available that provide forecasts in the 6 – 30 day range, especially beyond 14 days, which is considered the dynamical limit for weather forecasting based on the size and rotation rate of the planet as well as the gasses that make up our atmosphere.