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The bottom diagram is the snow depth analysis by the Swedish meteorological service.  There are more observations than are shown plotted, and the rain shadow effect is not as well marked as suggested by model forecast or analyses.

Unrealistic extreme convective precipitation focussed near coastlines (Cy49 and earlier)

This effect can occur with onshore cyclonic flow of maritime air that is marginally unstable to sea surface temperatures.  At certain times SSTs can be higher close to coastlines than offshore.   In these cases the inshore sea surface temperature can be high enough for the convection scheme in IFS to trigger release of convection with high CAPE values.  Just upstream the lower sea surface temperatures offshore cannot overcome convective inhibition at low or mid-tropospheric levels.    The IFS convective scheme triggers Instantaneous shower development at each step but in Cy49 and earlier does not advect the showers down wind.  This results in repeated convective rainfall over the same inshore locations which can add up to large or implausibly large record-breaking near-coast totals (Fig9.6.2-2). Cy50r1 transfers some of the convective moisture and precipitation to the large scale precipitation calculations and this helps carry the effects of the convective precipitation inland from windward coasts.

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