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Deep moist convection happens when deep instability (steep mid-tropospheric lapse rates), moisture and lift are all in place together.  If any of these ingredients is missing, deep moist convection is impossible. 

Presentations of Extreme Forecast Index (EFI) for CAPE and CAPE-shear can help with the early identification of the potential for severe weather related to convection. 

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It is tempting to simply observe on forecast charts where large CAPE or CAPE-shear EFIs coincide with high rainfall from HRES when assessing the release of severe convection.  HRES forecast rainfall may be used in combination with convective EFIs in the short-range (up to T+48hr), but it should be remembered that HRES (& CTRL) is just another individual possible forecast.  In the short-range it is probably the most likely one, but in the medium-range its relative weight compared to ENS members decreases and it becomes ensemble Control (and HRES) become just as likely as any other ensemble member.  Then it is best to use a probability of precipitation forecast (PoP > 1mm/24hr) rather than a simple precipitation forecast throughout the whole forecast period (both short-range and medium-range).  These concepts are discussed below using one case as an example.

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