#!/bin/bash
s="...SUMMARY...
Severe thunderstorms are most likely across north-central/northeast
Texas and the Ark-La-Tex region during the late afternoon and
evening. Destructive hail and wind, along with a few tornadoes are
possible. Severe thunderstorms are also expected across the
Mid-South and Ohio Valley.

...North-central/northeast TX and southeast OK/ArkLaTex...
In the wake of a decaying MCS across the Lower Mississippi River
Valley, a northwestward-extending outflow boundary will continue to
modify/drift northward with rapid/strong destabilization this
afternoon particularly along and south of it. A quick
reestablishment of lower/some middle 70s F surface dewpoints will
occur into prior-MCS-impacted areas, with MLCAPE in excess of 4000
J/kg expected for parts of north-central/northeast Texas into far
southeast Oklahoma and the nearby ArkLaTex. Special 19Z observed
soundings are expected from Fort Worth/Shreveport to help better
gauge/confirm this destabilization trend and the degree of capping."

sed -n '/^\.\.\.SUMMARY\.\.\./,/^\.\.\./{//!p;}' <<< "$s"