Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Tue Nov 18 2025 03:54:22 AWUS01 KWNH 180354 FFGMPD CAZ000-180753- Mesoscale Precipitation Discussion 1230 NWS Weather Prediction Center College Park MD 1053 PM EST Mon Nov 17 2025 Areas affected...portions of southern California Concerning...Heavy rainfall...Flash flooding possible Valid 180353Z - 180753Z Summary...Flash flood potential continues for at least 2-4 more hours. Discussion...A warm conveyor continues to spread moderate to heavy rainfall into portions of southern California near the Los Angeles basin and adjacent areas of the Transverse Ranges. Recent observations suggest that 0.5 inch/hr rain rates were falling over or very near burn scars just north of Los Angeles, suggesting continued potential for excessive runoff and debris flows.=20 Mesoanalyses indicate a continued fetch of southwesterly 850mb flow into the region oriented parallel to the coastal ranges, supporting continued orographic enhancement of rain rates at times. PW values near an inch and weak surface-based instability also continue to support the convective nature of the activity and locally heavy rain rates.=20 Models suggest that these rates will continue to impact burn scar areas over the next 2-4 hours (through 07Z or so) while translating slowly eastward. Flash flooding will remain a possibility, though this risk should become more isolated with time as rain rates are expected to gradually weaken. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!_Lg5brlhc3l8TD-QR5rcay76pvzFWwwYGIJQpPeKzNXG0xFgdiYBDr3pyuoXkzT3fOGP= k9Y_FcFrxoaKrLCXc2oRlZY$ for graphic product... ATTN...WFO...HNX...LOX...PSR...SGX...VEF... ATTN...RFC...RSA...NWC... LAT...LON 34971836 34901737 34381647 33161635 32611652=20 32711701 33401774 34051865=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 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .