That is an extremely remote area. I have ventured west on state road 90 three times to Del Rio and I yet to have any luck at all. The country is full of hills and the road network is horrible at best, wit border patrol stops, and all I have had to show for it is an invitation to traffic court in Hondo for a busted headlight.
Though If you watch the radars on any day with half a chance of convection, you will see one or two cells start in mexico cross and into Terrel county with vils up to 80 and then die out as it approaches Pecos county. I have lost count the number of times I have watched that happen. On two occasions in June I saw two severe cells merge and head east, with reports of 3 inch hail or better and definite rotation, into Sanderson or even val verde county.
Its hit or miss and very very difficult to get to.
WW 792 has been issued for portions of eastern, central and northern Missouri. Tornado probablistic came up to 5% in the 2000 outlook. Convection has initiated in north-central Missouri and is rapidly moving off to the NE along the frontal boundary. Much of this appears to be in the form of convective clusters currently, but as time goes on, increased shear may support further surface-based development in discreet cells.
Noteworthy outlook language:
BAND OF 35-40 KT OF SWLY MID-LEVEL FLOW ALONG AND NORTH OF THE COLD FRONT WILL PROVIDE SUFFICIENT DEEP LAYER SHEAR FOR ORGANIZED STRONG TO SEVERE STORMS INITIALLY ACROSS NERN KS/NRN MO TO FAR SRN/SERN IA. ... ENHANCED LOW-LEVEL SHEAR PARAMETERS ACROSS PORTIONS OF ERN KS INTO MO ALONG THE CONVECTIVE OUTFLOW BOUNDARY AND WHERE THIS BOUNDARY INTERSECTS THE COLD FRONT WILL SUPPORT THE THREAT OF TORNADOES.