Forecasts are from initial conditions of the last 10 days, with four runs from each day (every 6 hours). Forecast ensembles consist of 40 members from an initial period of 10 days. The 1st ensemble (E1) is from the earliest 10 days, the 2nd ensemble (E2) from the second earliest 10 days, and 3rd ensemble (E3) from the latest part (10 days, more or less) of the month. Anomalies are mapped against a 1982-2010 hindcast climatology. Temporal correlations between hindcasts and observations are used as a skill mask for spatial anomalies. The precipitation anomaly is calculated as a percentage of deviation from model climatology 1981-2010 (historical average). The legend has been arranged as per the following table:


Legend category

Precipitation anomaly values

Very dry        

<-50%

Dry

-50% ~ -25%

Slightly dry        

-25% ~ -5%

Normal

-5% ~ 5%

Slightly wet        

5% ~ 25%

Wet

25% ~ 50%

Very wet        

>50%


The temperature anomaly is in degrees celsius, compared to the climatology 1981-2010 (historical average). Negative values mean lower than historical average (colder), positive value mean higher than historical average (warmer). The wind speed anomaly is in mm/second, compared to the climatology 1981-2010 (historical average). Negative values mean lower than historical average (less windy), positive value mean higher than historical average (more windy). The solar radiation (downward shortwave solar radiation) anomaly is in W/m2, compare to the climatology 1981-2010 (historical average). Negative values mean lower than historical average (less solar radiation), positive value mean higher than historical average (more solar radiation). Extreme Forecast Index (EFI) maps: In EFI the forecast probability distribution is compared to the model climate (M-climate) distribution for the chosen location, time of year and lead time. The underlying assumption is that, if a forecast is anomalous or extreme with respect to the M-climate, the real weather is also likely to be anomalous or extreme compared to the real climate. Negative values mean lower than historical average probability of extreme weather, positive value mean higher than historical average probability of extreme weather. The legend has been arranged as per the following table:


Legend category

EFI values\

Very Unusual Low        

-1.0 - -0.8

Unusual Low        

-0.8 - -0.5

Usual Low        

-0.5 - 0

Usual High        

0 - 0.5

Unusual High        

0.5-0.8

Very Unusual High        

0.8-1.0