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Charts available are: 2m temperature, surface temperature, total precipitation, mean sea level pressure, winds.   Click on the central small icon in the bottom right of the web frame to show the colour scale of values appropriate to each display.

Colouring on the charts is implies >90% significance for the anomaly .  This does not mean the white from ER-M-Climate.  White shading on the maps necessarily points to:only implies <90% significance of the anomaly and show where the ensemble forecast is not significantly different from the extended range climatology, according to a Wilcoxon-Mann-Whitney (WMW) test.  It does not necessarily point to a forecast of average

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nor to a 'don't know' forecast of climatology.

Further information can be gained by inspection of the Extended anomaly meteogram.  Click the mouse over any location on the ensemble charts to produce probability information in diagrammatic form.  Diagrams available:

• Extended anomaly meteogram.

meteogram form. 

The example (Fig8.2.3-1) shows white shading on the maps.  When presented with white shading at the location of interest, the user should inspect the anomaly Meteograms and CDFs to decide the likely anomaly and assess the confidence.

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Fig8.2.3-1:  Consider T2m temperature forecast anomalies from model climate at the location in southern Sweden (shown at X).

For week 1, the meteogram shows a high confidence forecast of low anomalies (box and whisker symbol quite short centred near 0ºC) implying near-normal mean 2m temperatures.  This is confirmed by the relatively vertical red CDF profile near the 0ºC anomaly line.

For week 5, the meteogram shows much less certainty in the anomalies (box and whisker symbol fairly extended) implying a larger spread of mean 2m temperature anomalies and mean 2m temperatures.  The CDF profile suggests the forecast is much like climatology as the red line of the forecast anomalies is almost coincident with the black line of the model climate distribution of anomalies.  Forecast and climatology are equally uncertain.

In both cases in this example there is white shading on the maps at location X. The example shows white shading on the maps cannot, of itself, point to a forecast of average (as at week 1) nor to a 'don't know' forecast of climatology (as at week 5)Click on the central small icon in the bottom right of the web frame to show the colour scale of values appropriate to each display.

Probability that weekly mean anomaly from anomaly from model climate greater climate greater than zero

The weekly anomaly probability charts display the probability that the weekly mean anomalies are greater than zero.  The probability is calculated from the number of ensemble members which show an anomaly within the higher half of the the ER-M-climate distribution. 

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Click on the central small icon in the bottom right of the web frame to show the colour scale of values appropriate to each display.

Any pixel that has high probability for lower (or upper) decile should have at least the same or higher probability for lower (upper) quintile and even higher for lower (upper) tercile.  On occasion this has not happened and is being investigated.

Multiparameter outlook - Extended range forecast

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Click on the central small icon in the bottom right of the web frame to show the colour scale of values appropriate to each display.

Any pixel that has high probability for lower (or upper) decile should have at least the same or higher probability for lower (upper) quintile and even higher for the tercile. 

Measures of skill of forecasts. 

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