What are MOS and MRF and what do they do?
Top of page Model Output Statistics (MOS): The Hydrometeorological Center of the National Environmental Prediction Centers (formerly National Meteorological Center) produces a short range (6 to 60 hours) MOS (Model Output Statistics) guidance package generated from the NGM (Nested Grid Model) for over 300 individual stations in the continental United States. These alphanumeric messages are made available at approximately 0400 and 1600 UTC for the 0000 and 1200 UTC forecast cycles, respectively. Model Output Statistics are a set of statistical equations that use model output to forecast the probability of precipitation, high and low temperature, cloud cover, and precipitation amount for many cities across the USA. The statistical equations were specifically tailored for each location, taking into account factors such as each location’s climate. To indicate snow and precipitation type forecasts, the message varies between the cold (September 16 through May 15) and warm (May 16 through Se
