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Yes, it’s still a week away but last night’s (0Z) GFS run is showing a strong cold front passage next Tuesday (10/18) accompanied by a decently vigorous upper level trough. I’ve been watching next week’s trends for a while now and the idea of a potential chase has been floating around for several days.

Per the GFS surface dew points increase to the mid-60s on Tuesday across Virginia. CAPE (instability) doesn’t look all that great but shear is robust. Thus this would be a typical HSLC (high shear/low CAPE) setup likely featuring low-topped storms with the potential for rotation. Whether or not the cells would be discrete or along a squall line depends on the shear orientation wrt the front.

Here’s the 0-3 km energy helicity index (left) and supercell composite parameter (right) maps at 21Z next Tuesday:

I’m not totally sold on this setup yet but it is encouraging. I could deal with another chase this fall before the convective season shuts down completely.