134  
AWUS01 KWNH 140920  
FFGMPD  
CAZ000-141518-  
 
MESOSCALE PRECIPITATION DISCUSSION 1223  
NWS WEATHER PREDICTION CENTER COLLEGE PARK MD  
420 AM EST FRI NOV 14 2025  
 
AREAS AFFECTED...PORTIONS OF SOUTHERN CALIFORNIA  
 
CONCERNING...HEAVY RAINFALL...FLASH FLOODING LIKELY  
 
VALID 140918Z - 141518Z  
 
SUMMARY...FLASH FLOOD POTENTIAL CONTINUES ACROSS PORTIONS OF  
SOUTHERN CALIFORNIA FOR AT LEAST ANOTHER 4-6 HOURS. AREAS OF 2-3  
INCH RAINFALL TOTALS ARE EXPECTED THAT COULD CAUSE EXCESSIVE  
RUNOFF AND DEBRIS FLOWS.  
 
DISCUSSION...FLASH FLOOD POTENTIAL WILL CONTINUE THROUGH AT LEAST  
15Z/7A PACIFIC TIME THIS MORNING. A FETCH OF STRONG ONSHORE FLOW  
CONTINUES JUST AHEAD OF A COLD FRONT ALONG THE COAST EXTENDING  
FROM NEAR PRB NEAR VBG. JUST AHEAD OF THIS FRONT, MESOANALYSES  
INDICATE A FOCUSED AREA OF 35 KNOT 850MB FLOW ORIENTED  
PERPENDICULAR TO THE WESTERN TRANSVERSE RANGES (SANTA BARBARA AND  
VENTURA COUNTIES). THIS ORIENTATION, ~1.5 INCH PW, AND MODEST  
INSTABILITY WAS SUPPORTING REPEATING HEAVY RAINFALL AT TIMES  
ACROSS THE DISCUSSION AREA. THE REPEATING NATURE OF THE RAIN WAS  
RESULTING IN SPOTS OF 1 INCH/HR RAIN RATES IN LOCAL AREAS FROM THE  
SANTA YNEZ MOUNTAINS THROUGH THE SIERRA MADRE MOUNTAINS AND  
SURROUNDING AREAS. LOW SPOTS WERE RESPONDING WITH RUNOFF OVER  
AREA ROADWAYS OVER THE PAST FEW HOURS, AND REPORTS OF FLOODING  
HAVE BEEN RECEIVED IN THE DISCUSSION AREA NEAR HIGHWAY 101.  
 
THE ONGOING SCENARIO WILL CONTINUE FOR ANOTHER 4-6 HOURS OR SO.  
THE MID-LEVEL SYSTEM PARTIALLY RESPONSIBLE FOR THE ONGOING HEAVY  
RAINFALL HAZARD HAS STALLED, AND THE ATTENDANT COLD FRONT WILL  
ALSO BECOME STATIONARY. MEANWHILE, 35 KNOT 850MB FLOW WILL  
CONTINUE TO IMPINGE ON THE TRANSVERSE RANGES AND PROMPT SEVERAL  
HOURS OF INTERMITTENT HEAVY RAIN. THE VERY HIGH PW VALUES AND  
LOCAL BURN SCARS YIELD CONCERN THAT LOCALLY SIGNIFICANT FLASH  
FLOODING COULD OCCUR. RAINFALL TOTALS OF 2-3 INCHES ARE ALSO  
POSSIBLE IN A FEW SPOTS THROUGH 15Z.  
 
AT SOME POINT AROUND/AFTER 15Z, 850MB WIND FIELDS SHOULD SLACKEN  
SOME AND RESULT IN A GRADUAL LESSENING OF HEAVY RAINFALL POTENTIAL  
ESPECIALLY AFTER 15Z.  
 
COOK  
   
..PLEASE SEE WWW.WPC.NCEP.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...HNX...LOX...  
 
ATTN...RFC...RSA...NWC...  
 
LAT...LON 35782038 35561882 34761781 34121776 33911846  
34422009 34702073 35072071 35342098  
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