MD 1016 CONCERNING SEVERE POTENTIAL…WATCH POSSIBLE FOR PORTIONS OF KANSAS
Mesoscale Discussion 1016 NWS Storm Prediction Center Norman OK 0349 PM CDT Tue Jun 13 2017 Areas affected...Portions of Kansas Concerning...Severe potential...Watch possible Valid 132049Z - 132315Z Probability of Watch Issuance...40 percent SUMMARY...Isolated to widely scattered thunderstorms with a severe hail/wind risk may develop in the 2130-0000Z time frame and continue into the evening. The area is being monitored for possible Severe Thunderstorm Watch issuance. DISCUSSION...The air mass east of a composite surface trough/dryline analyzed from the Hill City KS area southward to near Dodge City KS and farther south into the OK/TX Panhandles continues to undergo strong destabilization, owing to widespread insolation amid surface dewpoints holding in the lower/middle 60s. Diabatic-surface-heating- bolstered baroclinic circulations along the aforementioned composite boundary may support isolated to widely scattered surface-based convective initiation in the 2130-0000Z time frame, as lapse rates are approaching dry adiabatic in the lowest 3 km above ground west of this feature. The severe risk could also spread into the region from recently issued Watch 324 into the evening hours. Storm development may also be aided by modest large-scale ascent/midlevel cooling accompanying the southern extension of a speed maximum crossing the area, as implied by water vapor imagery. With 8.5-9.5 C/km midlevel lapse rates overlying the aforementioned moisture, SBCAPE of 3000-4000 J/kg will support robust upward convective-scale accelerations. Meanwhile, effective shear of 25-35 kt could support organized convective structures, with possible supercells. Forecast hodographs across the region are modestly long in the mid/high levels, with geometries of either straight or with one or two inflections. Resultant, storm-scale, upward perturbation pressure gradient forces could favor both left and right members of supercell splits, along with small convective clusters following potential mergers of initial cells. In addition to severe hail, amalgamating cold pools amid 1000-1700 J/kg of DCAPE may foster isolated to widely scattered severe wind gusts. Given the modest magnitude of large-scale ascent and somewhat modest deep shear magnitude, severe coverage may be limited, but may be sufficient for Severe Thunderstorm Watch issuance by this evening. Convective and environmental trends will continue to be monitored. ..Cohen/Hart.. 06/13/2017 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...TOP...ICT...GID...DDC... LAT...LON 38349893 38659903 38849949 39419953 39899926 39979857 39879803 39289781 38549789 38329845 38349893
from SPC Mesoscale Discussions http://bit.ly/2s7FLEg
Be First to Comment