IEM Daily Feature
Thursday, 23 December 2010

Evolution of the forecast

Posted: 23 Dec 2010 05:57 AM

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Ames data was grid point sampled from the 0.5deg GFS data.
The GFS weather forecast model is run by the US government and produces forecasts from the current time out to about two weeks into the future. The model runs for the past week have been advertising a snow storm for today into Christmas Eve. This forecast has evolved over time though as is presented by the featured chart. Each row in the chart represents a successive forecast model run. The area in white is outside the time domain of the given model's run output data (8 days). Model runs made on the 19th dumped a fair amount of snow on Ames for today, but have since backed off on the amounts and delayed the onset by 12 or more hours. Making sense of this changing forecast is one of the reasons why we still have humans diligently creating forecasts each day.

Good = 49
Bad = 12

Tags:   model