Re: OMG!!!

FXUS66 KLOX 231136
AFDLOX

SOUTHWEST CALIFORNIA AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LOS ANGELES/OXNARD CA
344 AM PDT SUN JUL 23 2006

...DANGEROUSLY HOT ACROSS SOUTHWESTERN CALIFRONIA AGAIN TODAY...
...POTENTIAL FOR FLASH FLOODING IN THE MOUNTAINS...THE ANTELOPE AND
CUYAMA VALLEYS...AND THE INTERIOR VALLEYS OF SAN LUIS OBISPO
COUNTIES...

.SHORT TERM...WHAT A DAY SATURDAY! HIGHS WERE BETWEEN 108 AND 115 IN
MOST VALLEY LOCATIONS. WOODLAND HILLS (FORMERLY KNOWN AS THE CANOGA
PARK/PIERCE COLLEGE SITE) REACHED 119 DEGREES...AN ALL-TIME RECORD
SINCE RECORDS BEGAN THERE IN 1949. AFTER A PRELIMINARY LOOK AT
WEATHER RECORDS...IT APPEARS THAT THIS MAY BE THE HIGHEST
TEMPERATURE EVER RECORDED AT AN OFFICIAL OBSERVATION SITE IN LOS
ANGELES COUNTY. SOME TSTMS DEVELOPED LAST EVENING ACRS CSTL
SXNS OF L.A. COUNTY...BUT THOSE HAVE SINCE DISSIPATED. OTHER
ISOLATED TSTMS WERE DEVELOPING ACRS THE CSTL WATERS AND
TO ACRS THE SERN DSRTS OF CA. BASICALLY SKIES WERE MOSTLY CLEAR TO
PTLY CLOUDY ACRS THE FCST AREA ATTM.

PRES GRADS WERE ABOUT 2 MB OFFSHORE BETWEEN LAX AND DAG...ALMOST
UNHEARD OF FOR JULY. PROFILER DATA WAS ACTUALLY SHOWING A COUPLE OF
DEGREES OF WARMING THRU MOST OF THE ATMOSPHERE FROM THIS TIME
SATURDAY MORNING. THE 06Z WRF NOW SHOWS QUITE A BIT OF COOLING AT 950
MB...BUT THE 06Z RUN INITIALIZED VERY POORLY...SO IT HAS BEEN
DISCOUNTED. BASED ON CURRENT 950 MB TEMPS...THICKNESSES AND
PRES GRADIENTS...WOULD EXPECT TEMPS TO BE NOT MUCH DIFFERENT
FROM SAT IN MOST AREAS. HOWEVER...THERE IS QUITE A BIT MORE MOISTURES
IN THE ATMOSPHERE...AND THERE WILL LIKELY BE MORE IN THE WAY OF MID
LVL CLOUDINESS. IN ADDITION...THE GFS AND THE EARLIER RUN OF THE
WRF SHOWED GRADS TRENDING ONSHORE THIS AFTERNOON. THEREFORE...
BLV TODAY WILL BE A FEW DEGREES LESS HOT IN MOST AREAS. BUT...
THE DANGEROUSNESS OF THE HEAT SHOULD NOT BE UNDERPLAYED TODAY...
SINCE THE TEMP CHANGE LIKELY WILL BE HARDLY NOTICEANLE. STILL
XCPT HOTTEST LOCATIONS IN THE VLYS...LOWER ELEVATIONS IN THE
MTNS AND THE ANTELOPE VALLEY TO RISE TO BETWEEN 108 AND 115
DEGREES...WITH TEMPS ACRS INLAND SECTIONS OF THE CSTL PLAIN...AT
LEAST ACRS L.A. COUNTY APCHG OR EXCEEDING 100 DEGREES. WITH THE
RELATIVELY HIGH HUMIDITY VALUES...HEAT INDEX READINGS WILL RISE
TO BETWEEN 105 AND 115 IN MANY AREAS AWAY FROM THE COAST...
POSSIBLY REACHING 120 IN SOME LOCATIONS IN THE VALLEYS. EXCESSIVE
HEAT WARNINGS ARE IN EFFECT FOR THOSE AREAS...XCP FOR THE ANTELOPE
VALLEY...WHERE THRESHOLDS FOR EXCESSIVE HEAT WARNINGS ARE HIGHER.

THE OTHER ISSUE FOR THE DAY WILL BE CONVECTION. WATER VAPOR IMAGERY
INDICATES THAT SUBTROPICAL MSTR HAS SPREAD ACRS THE ENTIRE AREA
IN DEEP SELY FLOW THRU MID AND UPPER LVLS OF THE ATMOSPHERE. GOES
IMAGERY SHOWED PRECIPITABLE WATER VALUES OVER 1.5 INCHES ACRS MUCH
OF THE AREA. THE CURRENT RUN OF THE WRF HAS A VERY ERRONEOUS PRECIP
BULLSEYE JUST OFF THE L.A. COUNTY COAST AND APPEARS TO BE SUFFERING
FROM SEVERE CONVECTIVE FEEDBACK ISSUES. THE EARLIER RUN OF THE WRF
SHOWED FAIRLY DECENT K INDEX AND LIFTED INDEX VALUES ACRS THE
AREA. BOTH THE GFS AND THE 00Z WRF SHOWED A COUPLE OF WEAK
UPPER VORTS ROTATING THRU THE AREA WHICH COULD HELP TRIGGER
CONVECTION...AS COULD OUTFLOW BOUNDARIES FROM THE TSTMS CURRENTLY
ROLLING ACRS THE DSRTS TO OUR SE. SO...XPCT A DECENT AMOUNT OF
SHOWER/TSTM ACTIVITY TO DEVELOP TODAY...ESPECIALLY FROM THE
MTNS AND INTERIOR VLYS OF SERN SLO AND ERN SBA COUNTIES INTO THE
MTNS OF L.A. COUNTY AND THE ANTELOPE VLY. MID LVL WINDS WILL BE
VERY WEAK...SO THE POTENTIAL CERTAINLY EXISTS FOR FLASH FLOODING
WITH THESE STORMS. HAVE ISSUED A FLASH FLOOD WATCH FOR THE
MTNS...THE ANTELOPE AND CUYAMA VALLEYS AND THE INTERIOR VLYS OF SLO
COUNTY. SINCE THE MID LVL FLOW IS SUCH THAT SOME OF THESE SHOWERS
AND TSTMS COULD DRIFT INTO CSTL AND VLY ZONES...AND SINCE CONDS
ARE FAVORABLE FOR TSTM DEVELOPMENT JUST ABOUT ANYWHERE...WL GO
WITH 20 PERCENT POPS IN CSTL AND VLY ZONES TODAY.

LITTLE CHANGE IN MID/UPPER FLOW OR MOISTURE PROFILES THROUGH
TONIGHT...SO WILL KEEP CHANCE OF SHOWERS/TSTMS IN MTNS AND
ANTELOPE VALLEY...WITH SLIGHT CHANCE W OF THE MTNS. SHOULD BE
ANOTHER WARM AND HUMID NIGHT ACRS THE AREA.

UPPER HIGH OVER THE 4 CORNERS AREA WILL DEFINITELY BEGIN TO
WEAKEN ON MONDAY. WITH LOWERING HGTS AND AN INCREASE IN ONSHORE
FLOW...TEMPS SHOULD BE DOWN SEVERAL DEGREES IN CSTL AND VLY ZONES.
STILL...IT MAY BE HOT ENOUGH TO REACH EXCESSIVE HEAT WARNING
LEVELS AGAIN MONDAY AFTERNOON IN THE VLYS AND IN LOWER MTN
ELEVATIONS. WILL LET THE DAY SHIFT DECIDE ON EXCESSIVE HEAT
WATCH POTENTIAL FOR MONDAY. IT LOOKS LIKE THE BEST MSTR WILL
BEGIN TO SHIFT EWD ON MONDAY...WITH THE BEST THREAT OF CONVECTION
ACRS THE MTNS OF L.A. AND VTU COUNTIES AND THE ANTELOPE VLYS.
STILL LOOKS LIKE A SLIGHT CHANCE OF TSTMS ACRS INTERIOR SLO AND SBA
COUNTIES AND IN THE FOOTHILLS ABOVE THE L.A./VTU COUNTIES MON
AFTERNOON AND EVENING.

WEAK UPPER TROUGH MOVING INTO THE PAC NW WILL HELP KNOCK DOWN THE
RIDGE A BIT MORE ON TUE...AND ONSHORE FLOW WILL CONT TO INCREASE.
XPCT SEVERAL MORE DEGREES OF COOLING ACRS MOST AREAS ON TUE.
LOOKS LIKE SOMEWHAT LESS OF A CHANCE OF TSTMS TUE...BUT THERE
WILL BE ENOUGH MSTR AND INSTABILITY TO LEAVE AT LEAST SLIGHT CHANCE
FOR THE MTNS OF L.A. AND VTU COUNTY AND THE ANTELOPE VLY.

.LONG TERM...MODELS SHOW LITTLE CHANGE IN THE UPPER PATTERN WED
THRU FRI...WITH WK SLY FLOW ALF ACRS THE FCST AREA BETWEEN
A STRONG UPPER HIGH OVER THE S CENTRAL U.S. AND A WEAK TROUGH OFF
THE CST. THERE SHOULD BE A RETURN TO NIGHT/MORNING LOW CLOUDS
AND FOG IN CSTL SXNS...BUT THEY SHOULD REMAIN CONFINED TO THE
CSTL PLAIN. THERE WILL CONT TO BE A SLIGHT CHANCE OF AFTERNOON
AND EVENING SHOWERS/TSTMS IN THE MTNS OF L.A./VTU COUNTIES
THROUGH AT LEAST FRI. MAX TEMPS WILL LOWER A BIT MORE ACRS THE
AREA ON WED...POSSIBLY RETURNING TO NEAR NORMAL W OF THE MTNS.
THIS COOLING HAS BEEN OVERDONE BY THE MODELS MANY TIMES THIS
SUMMER...SO CONFIDENCE IN TEMPS RETURNING TO NORMAL LEVELS
IS LIMITED.

&&

.AVIATION...
INTENSE THERMAL HEATING WREAKING HAVOC WITH TYPICAL JULY WEATHER
PATTERNS AT ALL TAF SITES. MARINE LAYER NON EXISTENT. WINDS ESP
INLAND WILL COME FROM ODD DIRECTIONS AND DISPLAY MUCH MORE
VARIABILITY THAN NORMAL. NICE SUB TROPICAL MOISTURE PUSH WILL ALLOW
FOR A SLIGHT CHC OF TSRA AT ALL TAF SITES TODAY ALTHOUGH BEST CHANCE
FOR TSRA WILL BE OVER THE MTNS AND ANTELOPE VLY. WILL MENTION VCTS
IN KPMD AND KWJF OTHER TAFS WILL HAVE NO MENTION OF TSRA DUE TO ONLY
A 10 OR 20 PERCENT CHANCE OF A TSRA MOVING OVER A PARTICULAR RUNWAY.

&&

.LOX WATCHES/WARNINGS/ADVISORIES...
EXCESSIVE HEAT WARNING (SEE LAXNPWLOX).
FLOOD WATCH (SEE LAXFFALOX).

&&





PUBLIC...BRUNO
AVIATION...RORKE