Profiles that are difficult to assess, yet may be associated with weak supercell tornadoes

Assessment of the following profiles and examples falls into a "gray" area between environments that appear to be more straightforwardly tornadic or nontornadic.   Unfortunately, this is how many situations are in the real world.

Example 5a.  Parameters in this example are difficult to assess, with marginal shear-CAPE combinations because of the relatively small CAPE., and somewhat less-than-desirable deep layer shear due to the unidirectional profile.  Something that stands out is that the CAPE in this profile is "split" by an inversion around 700mb, resulting in 2 different LFCs and leaving a pocket of low-level CAPE disconnected from CAPE higher in the profile.  This is probably not helpful for updraft organization and intensity.  On the other hand, 0-1 km SRH is quite large and the low-levels are quite humid with small CIN.  With the strong wind fields, this situation would bear careful watching, even though the CAPE profile appears marginal for supporting supercell tornadoes.  Also, with the strong low-level winds (50 kts +) just 1 km above the surface, damaging convective winds would appear possible.

(RUC-2 analysis at Meridian, Mississippi, 17 UTC 11/29/01, updated by 17 UTC surface ob at MEI):
  JAN base refl. 1704 UTC 11/29/01

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Example 5b:  This is another environment that is difficult to assess.  All parameters are at least "marginal" in value, but shear-CAPE combinations and vertical shear are not impressive. This suggests that weak tornadoes are possible, but that significant tornadoes are less likely.  Unfortunately, many situations fall into "marginal" or "gray" areas like this example, particularly in the warm season.  There were several brief weak tornado reports with the supercell indicated on radar associated with this case.

(RUC-2 3-hr forecast for Winfield, Kansas, valid 00 UTC 6/6/01, updated by 01 UTC surface ob at WLD):
  radar mosaic at 0015 UTC 6/6/01

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Example 5c:  This situation appears less marginal than the previous example, with all parameters falling within ranges suggesting that support for supercell tornadoes is at least "ok".  Compared to example 5b, this environment has more SRH,  good shear-CAPE combinations, lower LCL and LFC heights, and very humid low-levels with virtually no CIN.  This suggests that supercell tornadoes are quite possible.  Only a weak tornado occurred with the supercell indicated on radar below, even though the environment suggested that significant tornadoes were possible.

(RUC-2 3-hr forecast for Austin, Texas, valid 21 UTC 11/15/01, updated by 21 UTC surface ob at AUS):
  EWX base refl. at 2146 UTC 11/15/01

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operational low-level thermodynamic parameter guidelines

Example 5d.   Similar to example 5b, all parameters in this example appear at least "marginal" or better, suggesting at least that weak tornadoes are possible.  Again, this is another example of a situation that is marginal at best and difficult to assess.   No tornadoes were reported with the supercell associated with this case, indicated on radar below.

(RUC-2 analysis profile at Medicine Lodge, Kansas, 00 UTC 6/21/01, updated by  01 UTC surface ob at P28):

    ICT base refl. 0113 UTC 6/21/01

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