National Weather Service Advisory

THE NATIONAL WEATHER SERVICE IN SAN DIEGO HAS ISSUED AN * URBAN AND SMALL STREAM FLOOD ADVISORY FOR... SAN DIEGO COUNTY IN SOUTHWEST CALIFORNIA... THIS INCLUDES THE CITIES OF... VISTA... SAN DIEGO... RAMONA... POWAY... OCEANSIDE...NATIONAL CITY...LEMON GROVE...LA MESA...IMPERIAL BEACH...ESCONDIDO...ENCINITAS...EL CAJON...DEL MAR...CORONADO... CHULA VISTA...CARLSBAD...BORREGO SPRINGS... * UNTIL 315 PM PDT * AT 1217 PM PDT...SHOWERS WITH MODERATE TO HEAVY RAINFALL WERE MOVING WEST ACROSS SAN DIEGO COUNTY. HEAVIEST RAINFALL WAS OVER THE MOUNTAINS AND DESERT FOOTHILLS...BUT LOCALLY HEAVY RAIN WAS ALSO OCCURRING ON SOME COASTAL MESAS. RAINFALL WILL MOVE WEST AT 30 MPH. LOCAL RAINFALL RATES WILL EXCEED ONE-HALF INCH PER HOUR. ISOLATED THUNDERSTORMS WILL ALSO CONTRIBUTE TO HEAVY RAINFALL. PRECAUTIONARY/PREPAREDNESS ACTIONS... EXCESSIVE RUNOFF FROM HEAVY RAINFALL WILL CAUSE ELEVATED LEVELS ON SMALL CREEKS AND STREAMS... AND PONDING OF WATER IN URBAN AREAS... HIGHWAYS... STREETS AND UNDERPASSES AS WELL AS OTHER POOR DRAINAGE AREAS AND LOW LYING SPOTS.

IN HILLY TERRAIN THERE ARE HUNDREDS OF LOW WATER CROSSINGS WHICH ARE POTENTIALLY DANGEROUS IN HEAVY RAIN. DO NOT ATTEMPT TO TRAVEL ACROSS FLOODED ROADS. FIND ALTERNATE ROUTES. IT TAKES ONLY A FEW INCHES OF SWIFTLY FLOWING WATER TO CARRY VEHICLES AWAY.