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None of the parameters give information on the cloud and precipitation.  High CAPE released within a dry atmosphere may give only little amounts of cloud.  For heavy showery rain areas or severe storms it is necessary to have moisture available at the base of convection and preferably throughout the troposphere.  Generally IFS forecasts of rain areas prove helpful in giving this information.  However, release of the instability depends on CIN being overcome or else on some dynamic uplift higher in the atmosphere. Also, additional moisture at low levels (e.g. by sea breeze) can bring development of significant showers - see section on the impact of incorrect moisture.

The section on Convective cloud processes and precipitation gives more detail.

General rule for forecasting convective storms

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• Pilo: The forecast vertical profile at Pilio (Fig9.6.4-9) shows large CAPE but with relatively dry convection, possibly released by high surface daytime temperatures.  Very little moisture is indicated and precipitation looks very unlikely.  However some moisture is available locally over mid-Greece mainly at medium levels producing possible local showery outbreaks given some form of dynamic uplift.  The relevant wind shear to consider for this is probably between medium and upper tropospheric levels rather than between lower and medium levels (the bulk shear).  Inspection of the hodograph suggests the upper tropospheric shear is not great, so shower organisation/activity would lack this element of support.  Note, however, that heavy medium level showers can penetrate downwards through underlying dry layers more than IFS forecasts tend to suggest, even reaching down to the surface.  Ensemble Control Forecast show a very humid boundary layer at Pilio, but it would require large energy input at the surface (2m temperatures above about 35°C) to overcome the large CIN and to lift the low level moisture to release moist convective cells.
• Kavala: The forecast vertical profile at Kavala (Fig9.6.4-8) shows rather less CAPE and CAPE-SHEAR but with an almost saturated atmosphere and absolute instability at around 750hPa.  Recall also that the max CAPE-Shear over the previous 6hrs was higher.  So very active moist convection is extremely likely in the northern Greece region.  Inspection of the hodograph suggests significant shear throughout lower and medium layers allowing separation of up draughts and down draughts with persistent active precipitation cells.  

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Fig9.6.4-10: Sequence of EFI precipitation charts from four EFI runs at 24hr intervals (DT 12UTC on 6, 7, 8, 9 July 2019). Increasingly high EFI precipitation values identify the areas at greatest risk.

(FUG Associated associated with Cy50r1)