Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Fri Feb 07 2025 03:49:46 AWUS01 KWNH 070349 FFGMPD CAZ000-070948- Mesoscale Precipitation Discussion 0026 NWS Weather Prediction Center College Park MD 1048 PM EST Thu Feb 06 2025 Areas affected...portions of southern California Concerning...Heavy rainfall...Flash flooding possible Valid 070348Z - 070948Z Summary...Increasing onshore flow is interacting with the Transverse Ranges in southern California to produce scattered showers and locally heavy rainfall. Rainfall totals of 0.25-1 inch are possible through 10Z/2am and beyond. Excessive runoff and debris flows are a distinct possibility - especially near sensitive areas of variable terrain and near burn scars.=20 Discussion...Over the next several hours, a strong low-level cyclone (currently centered near Eureka) will migrate northeastward toward Oregon. As this occurs, strong southwesterly low-level flow will increase across portions of southern California especially near terrain-favored coastal ranges. Moist air (characterized by 1-1.1 inch PW values) will accompany the increasing flow and become forced over the Transverse Ranges, resulting in areas of orographically enhanced moderate to heavy rainfall. This process is already underway, with spots of 0.2-0.4 inch/hr rain rates already observed west of Los Angeles in the past hour very near Malibu and Castaic. These trends are expected to continue, and a roughly 6-12 hour window of heavier rainfall potential will exist across the discussion area continuing into the overnight hours (perhaps through 12Z-15Z Friday). These areas of heavy rainfall will occur in areas of sensitivity from both terrain and burn scars from recent fires across the region. As a result, areas of flooding and debris flows are possible. Rainfall totals of 0.25-1 inch are probable through 10Z, with locally higher amounts (exceeding 1.5 inches) possible in terrain-favored areas. Cook ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!8xHNefkHYP3_lJgJJICRRL1GK8_LbVx7lSPiJ3pel_wzghsP-I4EeifkSzULBluoOydH= JBQwRntAtlaAIl5l-aQqq0E$ for graphic product... ATTN...WFO...HNX...LOX...SGX...VEF... ATTN...RFC...CNRFC...NWC... LAT...LON 35242052 35241936 35121841 34921756 34291731=20 33971765 34001857 34512041 34842065=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) .