


Flash Flood Guidance
Issued by NWS
Issued by NWS
063 AWUS01 KWNH 140535 FFGMPD CAZ000-141134- Mesoscale Precipitation Discussion 1195 NWS Weather Prediction Center College Park MD 135 AM EDT Tue Oct 14 2025 Areas affected...portions of central and southern California Concerning...Heavy rainfall...Flash flooding likely Valid 140534Z - 141134Z Summary...Strong onshore flow will continue to promote areas of heavy rainfall, with rates of 0.5-1 inch/hr becoming possible along upslope terrain areas. Flash flooding is likely - especially where heavier rainfall can materialize across burn scars and other sensitive areas. Discussion...A strong mid-upper low centered just west of San Francisco continues to move very slowly while promoting strong onshore flow across coastal areas of central California. Cold upper levels has fostered areas of 500 J/kg MUCAPE, promoting heavier rainfall in occasional convective bands that have traveled toward land on the southern and eastern peripheries of low. A belt of strong low- to mid-level flow (around 30 knots at 850mb) is oriented parallel to coastal ranges between Monterey and San Luis Obispo and was also aiding in heavy rainfall via orographic lift. The heaviest rain was located along and just ahead of a cold front that was migrating southward along the coastline near Monterey. Over time, the strongest of onshore flow will shift southward along the coast toward the Transverse ranges. 1-1.2 inch PW values and minimal instability will continue to promote heavy rainfall and rain rates exceeding 0.5 inch/hr at times. Areas of southern California (including the Transverse Ranges and Los Padres National Forest) will likely experience the heaviest of activity through 12Z. Local burn scars will enhance rainfall potential, and typical low-lying, flood prone spots will also be susceptible to flash flooding. An additional area of lighter rain is likely to be maintained across portions of central California and the southern San Joaquin Valley. Rain rates should be a bit lighter in most of these areas (0.1-0.5 inch/hr), but should persist for several areas and cause at least minor runoff issues. Cook ...Please see www.wpc.ncep.noaa.gov for graphic product... ATTN...WFO...HNX...LOX...MTR...SGX...STO... ATTN...RFC...RSA...NWC... LAT...LON 38842155 38022017 37111947 36371911 35691934 35001888 34561784 33881774 33511810 33921923 34602076 35982190 36902208 37802222 38582215