Forecast models have backed off on the amount of available moisture over the southern Piedmont Friday afternoon. (Hence CAPE values have diminished.) Here is this morning’s NAM dewpoint graphic for 21Z Friday (GFS looks similar):
Note the plume of higher dewpoints both west of the mountains and up the eastern coastline. Now, check out the NAM surface map for the same time (21Z):
The wind barbs and pressure isobars seem to indicate a lee trough over the southern Piedmont of Virginia. Combining that thought with the low dewpoints over the same area makes me think of a localized dryline.
So now I’m wondering…could a mini-dryline provide sufficient lift to fire storms Friday afternoon? Given that bulk shear values are >40 knots and are oriented almost perpendicular to this “dryline” might there be one or two discrete storms that could fire and organize over Bedford or Campbell county? Is a “mini-supercell” or two wishful thinking?
Hmmmm…..and no, this is NOT an April Fool’s joke!