####018002203#### AWUS01 KWNH 170112 FFGMPD TNZ000-KYZ000-MOZ000-ARZ000-170415- Mesoscale Precipitation Discussion 0280 NWS Weather Prediction Center College Park MD 912 PM EDT Fri May 16 2025 Areas affected...Northeast AR...Northwest/Northern Middle TN...Bootheel of MO... Concerning...Heavy rainfall...Flash flooding possible Valid 170110Z - 170415Z SUMMARY...Upstream redevelopment and flattening steering flow support training environment for increasingly efficient rainfall producing thunderstorms. DISCUSSION...Regional RADAR and GOES-E 10.3um EIR loop shows line of severe/enhanced V overshooting top signatures continue to back-build along/ahead of the slowly advancing cold front across SE MO into NW AR. Strong speed shear aloft shows narrow wedge but fairly undirectional steering flow, generally parallel to the developing line along the front. Surface inflow of low to mid 70s Tds on 15-20kts of flow, veers to 45kts out of the WSW at 850mb, increasing moisture flux convergence to the updrafts. The deeper aligning LLJ is also increasing overall moisture values from 1.5 toward 1.7/1.8" in total PWat values. As such, rainfall efficiency is increasing with rates currently reaching 1.5"/hr but will start climbing toward 2"/hr. Combine this with short-term training profiles and localized totals of 2-4" are becoming increasingly possible, especially as mature cells to the north increase cold pool geneation and propagate more south of due east into the path of these upstream developers. Cells are along the south and southwest edge of areas that received heavier rainfall this morning and FFGs reflect this ranging to aroudn 1.5"/hr and 2-2.5"/3hrs. Further south of the area of concern where recent drier conditions have existed, FFG values are about a 'category' higher at 2-2.5"/hr and 2.5-3.5"/3hrs. Gallina ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...LZK...MEG...OHX...PAH... ATTN...RFC...LMRFC...OHRFC...NWC... LAT...LON 36658931 36618829 36608773 36568530 36118555 35548893 35299096 35639184 36249136 36609015 ####018000903#### PENA01 KWNH 171200 @UHPISF000CN MPDSUM@V2.0@0101700060@12170525@@0NMCGPHMPD P@!' `' ` @ & B7)p&PNAM02@@;;~~}}}}}}}}}~}}}~}~~~|y@@;@@;@@; ~~}|{z{}}}}}}~}}~}~~}~~}~}~@@ @@ @@1S0279 @@0280 @@d&MESOSCALE DISCUSSION SUMMARY GRAPHIC @@d& OF ALL VALID MESOSCALE DISCUSSIONS AT @@d& TIME OF PRODUCT CREATION:@@d& ISSUED 05/17/2025 0112Z @@ dNOAA/NWS/NCEP@@d WEATHER PREDICTION CENTER @@d FOR COLOR VERSION SEE: @@d WWW.WPC.NCEP.NOAA.GOV @