Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Sat Jun 10 2023 09:47:31 AWUS01 KWNH 100947 FFGMPD TXZ000-OKZ000-101446- Mesoscale Precipitation Discussion 0454 NWS Weather Prediction Center College Park MD 546 AM EDT Sat Jun 10 2023 Areas affected...in and near western OK Concerning...Heavy rainfall...Flash flooding possible Valid 100946Z - 101446Z Summary...Training thunderstorms showing some backbuilding characteristics should continue to persist for another several hours. Hourly totals to 2" and local amounts to 4" are anticipated. Discussion...A shortwave moving through the southern High Plains along with an outflow boundary and a surface low near Amarillo TX have joined forces to lead to backbuilding convection across the eastern TX Panhandle which is starting to lengthen into a training band across western OK. Precipitable water values of 1-1.25" lie in the region per RAP forecasts. Effective bulk shear is above 25 kts, which is organizing the forming training band. Low-level flow out of the southwest is advecting in MU CAPE of 2000+ J/kg from the southwest. While the mesoscale guidance has nothing in this exact spot, a signal for heavy rainfall was present in the guidance farther to the east across central OK, which appears to be telling the tale for future expectations even if their amounts appear deficient.=20 HREF probabilities of 0.5"+ indicate that 2-3 more hours of backbuilding should be expected with the apparent signal for this convection in the region forward propagating to the east around 15z, due to a combination of eastward shortwave progression and cold pool formation coincident with daytime heating/CIN reduction leading to a more unbalanced instability environment (low MLCAPE forming to the west-higher ML CAPE forming to the east) favorable for forward propagation. As hourly totals to 2" have occurred thus far, which are supported by the available moisture and instability, the expectation is for those totals to continue for as long as training and backbuilding continues. Local amounts of 4" are anticipated which would exceed the three hour flash flood guidance in the region. Higher totals can't be ruled out as the band appears to be lengthening at this time. This could lead to flash flooding, particularly in urban areas. Uncertainty in the exact evolution and significant model displacement from what's ongoing have lowered confidence enough in future expectations to keep the category possible rather than likely. Roth ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!5ySo4gB98j_xSna-RAtB63xno0aoTOyFNOT7q_VL3e4alOq5Zj8TaZAx8vTT-R95DyOe= DkJ0vv7OEC5R5sGy2g5YKGo$ for graphic product... ATTN...WFO...AMA...OUN... ATTN...RFC...ABRFC...NWC... LAT...LON 35689831 35179821 34989894 35350050 35679981=20 =20=20=20=20=20=20=20=20=20=20=20=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.14-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .