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Where medium level instability is forecast above a dry lower atmosphere, users should use forecast lightning charts and forecast vertical profiles to extend and improve precipitation forecasts.   Where medium level instability is forecast (even with only moderate CAPE), some additional showers should be forecast within the areas of forecast lightning.  Owing to resolution issues, forecast intensity of lightning strikes gives only a rough idea of regions where there is more active medium level instability but it does not reliably indicate that showers will penetrate to the surface, nor their intensity if they do so.  However, probability of precipitation should be increased. 

An example - Central Australia, 17 January 2019

Fig2.1.30: Forecast IFS data for central and northwest Australia 17 Jan 2019.  Local time is about 10hrs ahead of European time zones. The circled triangle locates Alice Springs.

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