Valid 291200Z – 301200Z
…THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS PORTIONS OF
CENTRAL/EASTERN OKLAHOMA…NORTH TEXAS…AND FAR WESTERN ARKANSAS…
…SUMMARY…
A threat for severe storms will exist across portions of
central/eastern Oklahoma, north Texas, and far western Arkansas this
during the overnight hours.
…Synopsis…
A broad upper-level trough across the West will shift
eastward/northeastward and reintensify across the north-central High
Plains by the end of the period. At the surface, a cyclone will
deepen in western/central Nebraska. As this occurs, a cold front
will rapidly advance across Oklahoma and North Texas during the
overnight. Modest moisture return ahead of the advancing front will
allow some potential for near surface-based storms, particularly
across far southeastern Oklahoma into portions of North Texas.
Storms are expected to remain elevated elsewhere across the Marginal
risk area.
…Central/eastern Oklahoma and North Texas…
Storms are expected to form along the cold front, primarily after
09Z when large-scale ascent is expected to be greatest. The greatest
uncertainty in this scenario is how far north moisture will be
transported. Ongoing cloud-cover and precipitation will likely
hinder surface-based destabilization, especially in northern
portions of the Marginal risk area. The greatest potential for near
surface-based storms appears to be across southeastern Oklahoma and
adjacent portions of North Texas. Overlap of modest MLCAPE (perhaps
around 1000 J/kg) and 40-50 kts of effective shear will support a
risk of mainly marginally severe hail and strong convective wind
gusts. Farther north, into northeastern Oklahoma and far western
Arkansas, storms are likely to remain elevated. However, sufficient
shear, though weaker than points southward, will support some risk
for marginally severe hail.
..Wendt/Broyles.. 11/29/2019
$$