372 FXUS64 KTSA 192319 AFDTSA Area Forecast Discussion National Weather Service Tulsa OK 619 PM CDT Tue Jun 19 2018 .AVIATION... CONCERNING TAF SITES KTUL/KRVS/KBVO/KMLC/KXNA/KFYV/KFSM/KROG. VFR conditions will prevail through most of the first half of the TAF period. Cigs will lower to MVFR categories at most sites in the 09-13z time period, and may lift back to VFR by late morning. Rain and thunder chances will increase late in the period, with MVFR cigs and vsbys expected for the remainder of the period where thunderstorms occur. && .PREV DISCUSSION... /Issued 321 PM CDT Tue Jun 19 2018/ DISCUSSION... Isolated showers currently ongoing across the forecast area with any late afternoon convection expected to wane after sunset. Attention will turn to an expanding area of convection across the High Plains with one or more MCSs likely to emerge into the overnight hours. Trends in short term solutions have been consistent on weakening the storms into NE OK early Wednesday. The remnant outflow boundary and possible MCV presence will likely spark renewed convection across the forecast area during the day Wednesday. A more unstable airmass is likely to develop along the aforementioned sfc boundary with initial storms having severe potential. The instability axis may not expand too far eastward thus an early peak in severe potential is possible. The deepening closed mid level low over the central Plains will drop southward and push a synoptic scale frontal boundary through the region Wednesday night. Precip chances will also shift eastward with Thursday being mostly dry and pleasant and for late June. Flow aloft will remain seasonably strong from late week through early next week and likely act upon the sfc frontal boundary providing several opportunities for storm complexes to track across the region. Instability is also likely to become rather impressive along the frontal zone which will support some severe potential with each potential round of storms. Upper ridging strengthens early next week returning hot temps and lower rain chances. && .TSA WATCHES/WARNINGS/ADVISORIES... OK...None. AR...None. && $$ AVIATION.....23