Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Jan 03 2023 06:19:25 AWUS01 KWNH 030619 FFGMPD TNZ000-MSZ000-LAZ000-ARZ000-TXZ000-031200- Mesoscale Precipitation Discussion 0008 NWS Weather Prediction Center College Park MD 118 AM EST Tue Jan 03 2023 Areas affected...northern Louisiana, southern Arkansas, northwestern Mississippi, southwestern Tennessee Concerning...Heavy rainfall...Flash flooding likely Valid 030617Z - 031200Z Summary...Persistent, banded convection continues to produce rainfall rates at around 2-4 inches per 3 hours across southern Arkansas and northern Louisiana. These rates are expected to continue, posing significant flash flood risk through 12Z. Discussion...An axis of convection remains relatively persistent across portions of far east Texas and northwestern Louisiana (generally from near Lufkin, TX to near El Dorado, AR). Strong southerly flow has allowed for some airmass recovery in southwestern Arkansas, with surface-based instability now exceeding 500 J/kg per SPC mesoanalyses. Meanwhile, subtle mid-level forcing for ascent is overspreading the weakly-capped warm sector via mid-level shortwave troughs evident via model analyses across central/deep south Texas currently. This forcing has also ignited convection along a strong surface front located from near Paris, TX southwestward to near Austin. Both models and objective analyses indicate that the ongoing convective band across northwestern Louisiana will remain steady state for another 4-6 hours, with storms forming in that axis and moving downstream into southern/southeastern Arkansas. MRMS estimated rainfall rates of 2-4 inches per hour have been observed most of tonight along that axis and a number of flash flood impacts have been reported from near Shreveport to near El Dorado. Another 4-6 hours of these rainfall rates (prompting additional 3-6 inch rainfall amounts in a few spots) will exacerbate ongoing flash flood issues across the area, and significant flash flood impacts cannot be ruled out especially from near Shreveport to near El Dorado to near Pine Bluff/Monticello and vicinity - perhaps extending east to the Mississippi River.=20 Furthermore, the downstream airmass remains moist and unstable, and should support areas of 1-2 inch/hr rainfall rates through southeastern Arkansas and northwestern Mississippi - areas that have already experienced 1-2 inches of rainfall today and are currently experiencing low to moderate MRMS Flash responses.=20 Excessive runoff/flash flooding is also possible in these areas - generally from near Arkansas County, AR to near Memphis, TN. Lastly, the aforementioned cold front over central Texas will make steady eastward progress and its passage will represent the ending event for heavy rainfall in many areas, although it is not expected to reach northwestern Louisiana until after 12Z. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_I7iIcGVx_rSnM-npfqKtlSdLua_TCiN0ZCL9OsrEIDfZgOXGn5KBHAuESsSidkQ5gSl= XEpn1Lw2xj_yIpxmLzmV2wI$ for graphic product... ATTN...WFO...HGX...JAN...LCH...LZK...MEG...SHV... ATTN...RFC...ABRFC...LMRFC...WGRFC...NWC... LAT...LON 35748926 35728844 34968846 33778998 32719210=20 31679308 30929411 30869471 31809469 33269401=20 33829366 34509270 35299082=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) .