Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Apr 06 2023 09:45:25 AWUS01 KWNH 060945 FFGMPD TXZ000-061543- Mesoscale Precipitation Discussion 0162 NWS Weather Prediction Center College Park MD 543 AM EDT Thu Apr 06 2023 Areas affected...South-Central to Southeast TX Concerning...Heavy rainfall...Flash flooding possible Valid 060943Z - 061543Z SUMMARY...Slow-moving and locally repeating rounds of heavy showers and thunderstorms this morning may produce a threat for some flash flooding. DISCUSSION...The latest radar imagery continues to show a broken axis of heavy showers and thunderstorms lifting northeast across areas of south-central to southeast TX. The activity is being driven by a stripe of relatively strong frontogenetical forcing and coinciding with a well-defined pool of elevated post-frontal instability. Some right-entrance region upper-jet dynamics are also in place downstream of an upper-level trough seen over northern Mexico which is providing at least some modest deep layer ascent. MUCAPE values of 1000+ J/kg are in place and along with a substantial pool of moisture in the 850/500 mb layer that has subtropical origins from the eastern Pacific Ocean. This is helping to drive PWs of 1.5 to 1.6 inches based off recent GPS-derived data. The convection is relatively slow-moving and has been producing rainfall rates locally as high as 1.5 inches/hour, and given the locally repeating convective cells, some storm totals of as much as 2 to 3+ inches have already occurred. The overnight HREF guidance including a number of the HRRR runs have been notably underdone with their QPF coverage and totals, and have not had the level of convective organization correctly depicted that has actually panned out. Additional rounds of showers and thunderstorms are expected this morning as some intensification of the upper-jet forcing occurs which will be interacting with plenty of moisture and at least a favorable level of instability for sustainable convection. As much as an additional 2 to 4 inches of rain will be possible, and especially with the slower and locally repeating cell activity. FFG values have been coming down overnight from the earlier rounds of heavy rainfall, and these additional rains will favor a threat for some flash flooding going through the morning hours. Orrison ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_9m8gDupwAwC3UZJd8Ec0OI_lZy38h_RVT4jpTQj5_p9UNYXu4zZWaUg1NcA-f-HDQWY= WdL62wXscnp6Z6T3zgnXxek$ for graphic product... ATTN...WFO...BRO...CRP...EWX...FWD...HGX... ATTN...RFC...WGRFC...NWC... LAT...LON 31569520 30909470 30269516 29509606 28439719=20 27169820 26699864 26779920 27499946 28639919=20 29589859 30489777 31409621=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) .