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Fig9.2-11: An example of possible connection between IFS forecast 2m temperature (here using forecast EFI as a proxy) and forecast soil moisture content.  EFIs lower than -0.8 suggest extreme low temperatures compared to the model M-Climate and appear to be associated with high soil moisture content.  During the period, surface ground moisture appears to limit the amount of diurnal surface warming.  As the soil is forecast to dry out during the period, the 2m temperature is forecast to become unexceptional.  The reasons IFS are showing the temperature and moisture differences and uncertainties in analysis and forecasts are not clear.  Possible causes and correlations: 

• Surface ground moisture limits the amount of diurnal surface warming. As the The soil is forecast to dry out , during the 10 days and the 2m temperature is forecast to become unexceptional.
• Vegetation could be greener and more lush after previous wet period, leading to lower 2m temperature and higher 2m relative humidity being observed and forecast.
• The observed temperature could be colder than the first guess and thus in the analysis cause wetting of the model soil (despite no precipitation) and a higher relative humidity.
• Evapotranspiration could be mis-represented.
• Diurnal influxes of moist sea air may replenish moisture and/or not be well forecast either in depth or penetration.
• Insufficient information on atmospheric structure due to the lack of radiosonde . 

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