Flash Flood in California, July 7, 2006

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE SAN DIEGO CA
230 PM PDT FRI JUL 7 2006

.SYNOPSIS...ISOLATED THUNDERSTORMS IN THE MOUNTAINS AND HIGH DESERTS
INTO THIS EVENING. A SHALLOW MARINE LAYER AND ONSHORE FLOW WILL
CAUSE COASTAL LOW CLOUDS AND FOG IN THE NIGHTS AND MORNINGS.
OTHERWISE...FAIR EXCEPT FOR A FEW CLOUDS OVER THE MOUNTAINS DURING
THE AFTERNOONS. WEAK UPPER LEVEL LOW PRESSURE WILL BRING A LITTLE
DEEPENING OF THE MARINE LAYER AND COOLING NEXT WEEK.

&&

.DISCUSSION...FOR EXTREME SOUTHWESTERN CALIFORNIA INCLUDING ORANGE...
SAN DIEGO...WESTERN RIVERSIDE AND SOUTHWESTERN SAN BERNARDINO
COUNTIES...

STRATUS WAS INTO THE COASTAL AREAS AND FAR WRN SAN DIEGO INLAND
VALLEYS THIS MORNING. OTHERWISE...CLEAR EXCEPT FOR CU OVER THE
MOUNTAINS. ISOLATED THUNDERSTORMS DEVELOPED IN THE MOUNTAINS AND
HIGH DESERTS EARLY THIS AFTERNOON. THE 12Z NKX SOUNDING HAD A
MODERATELY STRONG INVERSION BASED NEAR 1200 FT...ABOUT 500 FT LOWER
THAN 24 HOURS PREVIOUS. ONSHORE GRADIENTS TO THE E WITH ABOUT 3 MB
SAN-IPL BUT WEAK OFFSHORE FROM THE N.

MODELS HAVE BEEN INCONSISTENT ON INCREASING MID LEVEL MOISTURE THIS
WEEKEND AND EARLY NEXT WEEK. AFTER TODAY...WILL CONTINUE WITH THE
IDEA OF JUST AFTERNOON CLOUDS OVER THE MOUNTAINS FOR NOW.
HOWEVER...WILL HAVE TO KEEP A CLOSE WATCH ON CU DEVELOPMENT EACH
AFTERNOON SINCE THE POSSIBILITY OF THUNDERSTORMS CANNOT BE
COMPLETELY RULED OUT. THE MARINE LAYER WILL REMAIN FAIRLY SHALLOW
AND COULD BE A LITTLE PATCHY TONIGHT DUE TO THE OFFSHORE TRENDS FROM
THE N. STRATUS SHOULD CONTINUE TO BE MOSTLY CONFINED TO THE COASTAL
AREAS SAT NIGHT. SLOWLY LOWERING HEIGHTS AND WEAK UPPER TROUGHING
WILL DEEPEN THE MARINE LAYER AND BRING A LITTLE COOLING SUN AND MON.
POSSIBLE WEAK EDDY MON MORNING.

LONGER RANGE PROGS INDICATE AN UPPER TROUGH NEAR THE W COAST WILL
SLOWLY MOVE E THROUGH MID WEEK FOR A CONTINUED COOLING TREND AND
SLOW DEEPENING OF THE MARINE LAYER. OTHERWISE...DRY FLOW ALOFT WILL
KEEP THE WEATHER FAIR. WARMER TOWARD THE END OF NEXT WEEK AS HEIGHTS
INCREASE.

&&

.AVIATION...OTHER THAN PATCHY STRATUS AND HAZE CLINGING TO SOME
BEACHES...THE STRATUS DECK HAD COMPLETELY CLEARED BY 20Z. LITTLE
CHANGE IN THE SYNOPTIC PATTERN IS EXPECTED...SO THE STRATUS DECK
SHOULD REDEVELOP BY 05Z NEAR THE COAST WITH BASES NEAR 1K FT MSL AND
TOPS NEAR 1.5K...THEN SPREAD LOCALLY INLAND INTO SOME COASTAL
VALLEYS OVERNIGHT. EXPECT MVFR CONDITIONS NEAR THE COAST...WITH
AREAS OF IFR CIGS/VIS AND LOCAL LIFR CONDITIONS JUST INLAND. FAR
INLAND VALLEY AIRPORTS AND PORTIONS OF INLAND ORANGE COUNTY ARE
EXPECTED TO REMAIN MOSTLY CLEAR.

OVER THE MOUNTAINS...JUST ENOUGH MOISTURE IS PRESENT FOR AREAS OF
MID-LEVEL BASED CUMULUS AND ISOLATED THUNDERSTORMS WITH TOPS TO NEAR
40K AND ASSOCIATED TURBULENCE AND LOW LEVEL WIND SHEAR. THE
CONVECTION IS EXPECTED TO DIMINISH QUICKLY AFTER 02Z.

&&

PUBLIC...ATKIN
AVIATION...JAD

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE SAN DIEGO CA
300 PM PDT FRI JUL 7 2006

CAZ055-056-058-060>062-081100-
SAN BERNARDINO COUNTY MOUNTAINS-
RIVERSIDE COUNTY MOUNTAINS-
SAN DIEGO COUNTY MOUNTAINS-
APPLE AND LUCERNE VALLEYS-
COACHELLA VALLEY-
SAN DIEGO COUNTY DESERTS-
300 PM PDT FRI JUL 7 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHWEST
CALIFORNIA.

.DAY ONE...TONIGHT
THERE IS A SLIGHT CHANCE OF THUNDERSTORMS THROUGH EARLY EVENING.
THE FLASH FLOOD POTENTIAL INDEX IS LOW...THE RISK OF FLASH FLOODING
IS MINIMAL.

.DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY

NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION WILL BE NEEDED UNTIL 6 PM.

MM