acus03 kwns 230715
Storm Prediction Center ac 230714
Day 3 convective outlook
National Weather Service Storm Prediction Center Norman OK
0214 am CDT Thursday may 23 2013
Valid 251200z - 261200z
..no severe thunderstorm areas forecast...
very slow/minor progression of the upper pattern is forecast for
Saturday /day 3/...though the overall western trough/Central Ridge/eastern
trough pattern will persist. At the surface...a low is prognosticated to
deepen just off the New England coast...but otherwise high pressure
should continue to prevail east of the MS River Valley. Farther
West...Lee troughing will again serve as a main focus for isolated
..nrn High Plains...
Saturday will likely be a very similar day to Friday /day 2/...with
the ridging across the plains and resulting large-scale
subsidence/capping largely hindering convective
development/intensity. While very isolated severe potential will
again exist across the central and southern High Plains...somewhat
greater threat may evolve across the eastern Montana/western South Dakota vicinity during
the late afternoon.
Here...models hint that a middle-level short-wave feature may eject
northeastward around the southeastern periphery of the main western trough toward the northern
High Plains. As this occurs...cap weakening and isolated storm
development appears possible near the Lee trough/within upsloping
low-level selys. With 35 knots swlys at middle levels anticipated...shear
would support updraft organization/rotation and attendant severe
potential. Thus -- will focus low severe probability across the northern
High Plains region this forecast.