Valid 190100Z – 191200Z
…NO SEVERE THUNDERSTORM AREAS FORECAST…
The risk for severe thunderstorms appears negligible across the U.S.
…01Z Outlook Update…
…Lower Missouri Valley…
Steepening of lapse rates associated with differential thermal
advection, in the exit region of a 70-80 kt digging northwesterly
500 mb jet streak, has contributed to sufficient destabilization for
convective development that has been able to produce at least some
lightning across northwest Missouri the past few hours. Based on
latest model output, including forecast soundings, this appears
rooted above the boundary layer, probably aided by low-level warm
advection. This may persist south-southeastward across the Missouri
Ozarks vicinity this evening, and perhaps through portions of
southeast Missouri by 06-08Z before diminishing.
The significant short wave trough now approaching the Pacific
Northwest coast is forecast to gradually split, downstream of an
amplifying mid/upper ridge. As the lead perturbation emerging from
this feature progresses inland later this evening/overnight, it
appears that its associated mid-level cold core (including 500 mb
temps of -24 to -26C) could contribute to favorable thermodynamic
profiles for convection capable of producing lightning.