the storm over the Concavity: satellite maps of east-central O.N.A.N. — "A hot moist ridge from the…"
A hot moist ridge from the Gulf of Mexico and an Arctic cold front had collided over the Concavity.
Context
The weather itself organized by the reconfigured map: "Satellite maps of east-central O.N.A.N. showed a white formation... that seemed to have what looked like claws," a blizzard that "collided over the Concavity" while "ATHSCME fans atop the wall north of Ticonderoga NNY" make "horizontal cyclones of snow." The televised storm is mapped onto O.N.A.N.'s political geography — the Concavity a meteorological as well as territorial fact, the border-fans visibly shaping the weather. The nation's map is the frame through which even snow is reported.