Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu May 09 2024 23:25:52 AWUS01 KWNH 092325 FFGMPD ALZ000-MSZ000-100430- Mesoscale Precipitation Discussion 0252 NWS Weather Prediction Center College Park MD 725 PM EDT Thu May 09 2024 Areas affected...Central Alabama...Eastern Mississippi... Concerning...Heavy rainfall...Flash flooding possible Valid 092325Z - 100430Z SUMMARY...Initially slow moving, intense thunderstorms to become more numerous with potential collisions and mergers after dark.=20 Widely scattered incidents of flash flooding will become possible through late evening into early overnight. DISCUSSION...GOES-E Visible imagery aids in boundary detection with old outflow boundary angled from the FL/GA/AL corner northeast to near Birmingham before starting to meld/intersect with the trailing edge of the northern stream cold front before it flattens east to west from K1M4 into northern MS. Additionally, milky appearance and some increased congestus denotes a west to east boundary that looks to be something the emanated from the Gulf this morning. There appears to be a discontinuity in the moisture/theta-E field in the lowest levels but not enough to be remarkable. Still between these boundaries, full sun and Tds in the mid-70s has resulted in ample unstable if capped environment.=20 However, GOES-WV and AMV along with RAP analysis fields denotes the approach of a mid-level lull in flow with subtle diffluence and speed divergence to locally enhanced mid-level cloudiness along the leading edge of 700-500mb moisture. The combination is resulting in scattered destabilization with best cells initially near BMX and low-level flow converge in the outflow boundary (nearly perpendicular as well with favorable westward curvature).=20 Additional cells are breaking out across E MS.=20=20 Total moisture to 1.75" and strong updrafts to support moisture flux into the column should support robust rainfall rates of 1-1.5"/hr probable. Quick cell motions may result in reduced rainfall totals, especially upstream with development over central MS into E MS, but in proximity to the outflow boundary, cells are likely to cluster/slow trying to anchor to the boundary much like the rotating cell in Shelby county. This will increase duration as well a potential mergers, resulting in short-term increase up to 2".=20=20 Hydrologically, west-central AL/eastern MS has been fairly dry, but eastern AL remains fairly wet; especially with this morning's heavy rainfall in the eastern quarter. MPD area aligns with 1-3hr FFG values of <2.5 and <3.5 respectively; where rain-rates/totals could be 1.5-2" and 2-3". Coverage of heavy rainfall is likely to be widely scattered with local focus where cells remain stationary or have upstream flanking line redevelopment that favors 1-2 hour repeating/training potential. Still the risk for flash flooding is non-zero and is considered possible locally within the area of concern through the early overnight period. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_CAyR6LpVATpGQK9_GQRmKAuRps707OC667zvqFy7VMXhQV8v47VdTxBw4W2PSIDP1LQ= F7mTj9LRFs2YokOKRdMkqyU$ for graphic product... ATTN...WFO...BMX...JAN... ATTN...RFC...LMRFC...SERFC...NWC... LAT...LON 33848712 33668600 32918546 32518527 32238577=20 32828687 32748890 33178923 33518891 33698817=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 3.20-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .