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• available on ecCharts and web open charts:
  • CAPE (from HRES or ENS control),
  • CAPE Extreme Forecast Index and CAPE-shear Extreme Forecast Index. 
  • probability of CAPE and CAPE-shear above or below a user-defined threshold.
  • 24h 4-value-maximum CAPE and CAPE-shear from M-Climate at various user-defined percentiles.

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Forecast vertical profiles are very helpful in assessing the potential for severe events.  The forecast vertical profile at Pilio 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 (Fig 2.1.26) 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.  HRES  HRES and some ENS members do 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.

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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.

• Fig2.1.30a: Total HRES 6hr precipitation T+21: DT 12UTC 16 Jan 19, VT 09UTC 17 Jan 19.
• Fig2.1.30b: Lightning density in 6hr (flashes 100km^-2hr^-1) T+21: DT 12UTC 16 Jan 19, VT 09UTC 17 Jan 19.
• Fig2.1.30c: ENS probability of total precipitation >1mm: DT 12UTC 16 Jan 19. VT 00UTC 17 Jan 19 to 00UTC 18 Jan 19.
• Fig2.1.30d: Total HRES 6hr precipitation T+21: DT 12UTC 16 Jan 19. VT 09UTC 17 Jan 19, and Observed lightning flashes VT 09UTC 17 Jan 19.
• Fig2.1.30e: Forecast vertical profile at Alice Springs T+18: DT 12UTC 16 Jan 19, VT 06UTC 17 Jan 19.

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