The first two items are unique output fields from NSSL's experimental Eta model forecasts. This configuration of the Eta uses the Kain-Fritsch (KF) convective parameterization rather than the operational Betts-Miller-Janjic (BMJ) scheme. One new output field from the KF scheme is the parameterized updraft mass flux (UMF). This field provides forecasters with an unique prediction of the strength of convective updrafts, and operational experience has shown the UMF to be a valuable complement to other indicators of convective intensity, such as convective rainfall, instability, wind shear, and helicity. The second output field is the source level for parameterized updrafts (USL). Convection arising from an elevated source poses a significantly reduced threat for tornadoes compared to surface-based convection. The USL field has shown remarkable skill in pointing forecasters to areas where convection is likely to be elevated, efficiently providing an extra layer of insight into forecaster interpretation of model forecasts.
Two additional, related tools have recently been introduced into operations. Specifically, diagnostic versions of the BMJ and KF convective parameterizations are now available as part of the SPC's N-SHARP sounding analysis program. With this capability, forecasters can easily evaluate any observed or model-forecast sounding using either one of these convective schemes. The graphical output shows step-by-step procedures used by the scheme and final convective adjustment profiles. This provides forecasters with direct knowledge of how convective schemes operate and how they are likely to modify soundings during the model integration, providing valuable clues for understanding sounding evolution in the Eta model. In addition, soundings can be easily modified within N-SHARP before calling the convective scheme, allowing forecasters to evaluate the convective threat after anticipated diurnal heating in the boundary layer, for example. All of these tools will be demonstrated at the conference and the benefits of this type of technology transfer will be discussed.
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