Valid 282000Z – 291200Z
…NO SEVERE THUNDERSTORM AREAS FORECAST…
Severe thunderstorms are not expected today or tonight.
The 10% general thunder area across parts of northern and central TX
has been removed with this update. Warm advection atop shallow
near-surface cold layer will increase overnight and modest
moistening above the warm layer between 850-700 mb will occur. Very
modest elevated instability will exist, but forcing through this
layer will be quite weak and most hi-res guidance does not develop
any substantial convection across central/northern TX before 12z
Further south near the Middle Texas Coast, easterly return flow will
bring near 70s F surface dewpoints north across southern TX ahead of
a stalled surface front. Warm advection/frontal convergence and
increasing instability should be sufficient for a few thunderstorms
in the last few hours of the forecast period.
.PREV DISCUSSION… /ISSUED 1108 AM CDT Mon Oct 28 2019/
Large-scale ridging off the South Atlantic coast will maintain
easterly flow and a maritime tropical air mass across most of the FL
peninsula. Isolated thunderstorms are possible during late
afternoon, mainly across central to north FL near a diffuse front.
Otherwise, the northeast extent of a deep moisture plume attendant
to a subtropical low should reach the northeast Gulf coast late in
the period, where around a 10 percent probability for elevated
thunderstorms should exist towards dawn.
Across parts of TX, low-level warm advection will strengthen
overnight atop a surface ridge, promoting the development of thin
elevated buoyancy. Latest guidance suggests the probability of
elevated thunderstorm development is only around 10 percent.
Background ascent beyond warm advection will be negligible through
12Z, as the region lies well away from the influence of a pair of
shortwave troughs embedded within the broader longwave from central
Canada to the western CONUS.