Valid 211300Z – 221200Z
…NO SEVERE THUNDERSTORM AREAS FORECAST…
Severe thunderstorms are unlikely today across the United States.
Progressive/split westerlies will reside over the CONUS through
tonight. Most relevant to thunderstorm potential will be multiple
shortwave troughs in the southern stream, including one impulse that
will spread from northern Baja this morning toward the Four Corners
by late afternoon and south-central Plains tonight.
…Northern New Mexico/southern Colorado…
Isolated to widely scattered thunderstorms are expected to develop
this afternoon across the region, influenced by a diurnal steepening
of low-level lapse rates and influences of the previously mentioned
shortwave trough as it approaches the region. While the boundary
layer will not be overly warm or moist, forecast thermodynamic
profiles this afternoon through early evening appear conducive for
the possibility of accumulating small hail/graupel, although
severe-caliber storms are not currently expected.
…South-central Texas to Louisiana…
Warm advection will contribute to an increase and east-northeastward
spread of elevated convection later this afternoon and tonight.
While organized/sustained severe storms are unlikely, modest
elevated buoyancy and strong shear through the cloud-bearing layer
could yield an instance or two of sub-severe hail.