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• available on ecCharts and web open charts:
  • CAPE (from HRES* or ENS control),from CONTROL-10/HRES)
  • 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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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:  from 9km resolution model DT 12UTC 16 Jan 192019,  T+21 VT 09UTC 17 Jan 192019.
• Fig2.1.30b: Lightning density in 6hr (flashes 100km^-2hr^-1) T+21: DT 12UTC 16 Jan 192019, T+21 VT 09UTC 17 Jan 192019.
• Fig2.1.30c: ENS probability of total precipitation >1mm: DT 12UTC 16 Jan 19. 2019, T+12 VT 00UTC 17 Jan 19 to T+36 00UTC 18 Jan 192019.
• Fig2.1.30d: Total HRES* 6hr precipitation T+21:  from 9km resolution model DT 12UTC 16 Jan 19. 2019, T+21 VT 09UTC 17 Jan 192019, and Observed lightning flashes VT 09UTC 17 Jan 192019.
• Fig2.1.30e: Forecast vertical profile at Alice Springs T+18: Springs DT 12UTC 16 Jan 19, T+18 VT 06UTC 17 Jan 192019.

Medium level thunderstorms developed and extended well into central parts of Australia (Fig2.1.30d, observed lightning) but no underlying surface rainfall is forecast (Figs2.1.30a & 2.1.30d), nor any probability of rain (Fig2.1.30c).  Forecast lightning flashes (Fig2.1.30b) is overly extensive in northwest Australia but although there is some indication in central parts it is under-indicated (compare with Fig2.1.30d). 

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The forecast vertical profile for Alice Springs (Fig2.1.30e) shows possible (surface-based) medium level instability with just moderate CAPE (e.g. cyan line construction).  Note that some ENS ensemble members have higher low-level dew points which means a lower CIN to initiate medium level convection with greater CAPE (e.g. red dashed line construction).  Further, if the boundary layer is moistened after any medium level showers penetrate to the surface then there is a higher likelihood of more energetic convection being released afterwards with much greater CAPE (e.g. black dashed line construction).

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