AllSky vs. ProbSevere: Which MLCAPE is best and where?

When utilizing the AllSky CAPE image product (MLCAPE), and comparing it to the ProbSevere MLCAPE values for reliability purposes of both tools, it is noticeable the differences between the two when there’s precip. This is due to the fact that most rain areas will not be able to be sampled by the satellite (clear/cloudy), and will be utilizing the GFS data in these areas where ProbSevere is located.

One way around this difference reliability issue is to scan the surrounding areas that are utilizing satellite data (preferably a “clear” spot), and in those cases, the MLCAPE values sampled seemed more comparable to the ProbSevere MLCAPE (RAP) of the storm than that of the GFS sampled MLCAPE data. The GFS sampled locations almost always show a lower MLCAPE value than the ProbSevere MLCAPE. The downside of sampling farther away from the storms/precip areas is that you are sampling rather far away from the storm environment. It’s also difficult to say that the ProbSevere MLCAPE is more accurate or not and what the reliability factors may be.

Below is an example of a storm over TX that is sampling the MLCAPE of the GFS (green text) and of the ProbSevere RAP (white text). -shearluck