Checking Medium-range Temperature Forecast skill Scores of All Models

Past 30 Days Skill Scores of Models Forecasting Temperature

Fig. 1-2: Skill scores for forecast 2-meter temperature by all operational models for the 0000 GMT and 1200 GMT model runs. Data provided by CWG/Storm Vista WX Models. Skill is on a zero (worst) to 1.00 (best) scale.

Discussion: Skill scores of forecast models for 2-meter temperatures across North America for the 6-10 and 11-15 day period do not render many surprises. In the 6-10 day period the European Ensemble (ECM ENS) edges the American Ensemble (GFS ENS) for best scores (Fig. 1). Conventionally, the ECM ENS dominates this category. However, the GFS ENS high scores is a surprise. Note the American Operational (GFS OP) is in last place which is also typical of this highly volatile model. Except for the GFS ENS, the 1200 GMT forecasts were slightly more skillful than the 0000 GMT forecasts.

In the 11-15 day period the ensembles are validated as the European and Canadian Operational (ECM and CMC) models extend to just 10 days. Once again the ECM ENS just barely edges the GFS ENS for best skill (Fig. 2). Note that the GFS OP lags well behind (as usual).

Summary: The 30-day skill scores for forecasting 2-meter temperature is a little better than average for days 6-10 and about average for days 11-15. The European Ensemble reigns supreme as the number one ranked model although the GFS ENS is (surprisingly) not far behind. The GFS OP ranks well behind as usual and should be used with caution.