Seasonal Forecasting Tools Climatology - Past history is used to predict the future. Persistence - Extrapolating recent past into the future. El Nino/Southern Oscillation - The most important recent discovery which has improved seasonal climate forecasts. Trends - Extrapolating multi-year and multi- decadal trends into the future. Soil moisture - In summer dry soil is associated with warm temperatures and vice versa. Atmospheric precursors – Using regional anomalies in sea level pressure, wave energy, etc. to predict future large-scale atmospheric patterns. Snow cover (winter months only) - Extensive snow cover is conducive to cold air masses.
October Siberian Snow Cover During the last 3 weeks of October 2009 there was a rapid increase in Siberian snow cover… …that was equivalent to the snow cover advance across North America from September through January