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SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 12/18/07 2343Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678
LATEST DATA USED: GOES-11 2330Z KUSSELSON
NOAA AMSU:2120Z DMSP SSMI/S:1645Z DMSP SSMI:1355Z-1609Z
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LOCATION...CENTRAL AND SOUTHERN CALIFORNIA...
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ATTN WFOS...VEF...SGX...REV...HNX...LOX...STO...MTR...
ATTN RFCS...CNRFC...
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EVENT...BURSTS OF HVY RAIN WITH QUICK MOVING FRONTAL BAND...BUT BAND
SLOWING A BIT AND MOISTURE FOCUSING MORE FOR CONTINUED POTENTIAL ISOLATED
PROBLEMS...
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SATELLITE ANALYSIS AND TRENDS...LATEST SATELLITE WINDS SHOWED JET CENTERED
FROM 43N/163W TO 44N/145W TO 39N/132W AND NOSING TO TROF NEAR 35N/127W.
STILL LOTS OF ROOM FOR TROF TO SLOW AND DEEPEN/DIG ESPECIALLY SINCE
UPPER WINDS MUCH LIGHTER ON EAST SIDE OF TROF.   BUT AS YOU KNOW THINGS
IN WEATHER CAN BE RELATIVE...AND WHEN YOU START OUT WITH A QUICK MOVING
FRONTAL BAND WITH MODERATE MOISTURE AND ONLY WEAK TO MODERATE FETCH
OF MOISTURE TRANSPORT...THEN YOU LOOK FOR OTHER REASONS FOR HVY RAIN
AND POTENTIAL ISOLATED URBAN TYPE FLOODING PROSPECTS.  THOSE THIS
LATE AFTERNOON ARE MORE OF FOCUSING OF NARROWING PW PLUME AND AS A
RESULT MORE OF A FOCUSING SHORT FETCH MOISTURE TRANSPORT...BUT THIS
CAN ALSO RESULT IN HIGHER SHORT TERM RAIN RATES THAT ARE NOT GOOD FOR
OROGRAPHIC AREAS...ESPECIALLY THOSE WITH BURN AREAS.  16KM AREAL AVERAGE
AMSU RAIN RATES AT 2120Z NOT ALL THAT IMPRESSIVE AT AROUND 0.10"/HR.
BUT THAT IS AN AREAL AVERAGE AND NOT TAKING INTO CONSIDERATION POCKETS
IN THAT 16KM AREA WHERE RAIN IS FALLING AT A HIGHER RATE...ESPECIALLY
OROGRAPHIC AREAS THAT ARE MORE FOCUSED THAN NORMAL ON A SMALLER AREA OVER
A SMALLER TIME FRAME.  SO THOUGH THIS NOT A LONG DURATION HEAVY PRECIP
EVENT...EVEN THOUGH TROUGH MAY BE SLOWING AND DEEPENING WITH MUCH FASTER
WINDS STILL COMING INTO THE TROUGH...SPEED NOT LIKELY TO SLOW FRONTAL
BAND SIGNIFICANTLY TO SIGNIFICANTLY INCREASE DURATION OF HVY PRECIP.
BUT WILL KEEP MONITORING AND IF THERE IS SLOW UP IN FRONTAL BOUNDARY AS
IT MOVES ACROSS S CA THRU THIS EVENING...HIGHER AMOUNTS...LONGER DURATION
PRECIP WOULD NATURALLY LEADER TO A WIDER/LONGER DURATION URBAN PROBLEM.
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ALSO OF NOTE ON 2120Z AMSU PASS WAS MAX RAIN RATE OF 0.25"/HR AT
32.5N/125W.  THAT CONVECTION WILL HAVE TO BE WATCHED FOR FAR S CA AREAS
LATER THIS EVENING/TONIGHT AS THIS BAND IS WITH FRONT THAT IS LEFT BEHIND
THE ENHANCED CLOUDS MOVING CENTRAL/NORTHERN PORTION OF S CA RIGHT NOW.
WILL CONTINUE TO MONITOR...
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SEE NCEP HPC DISCUSSION AND QPF/S FOR FORECAST.
....NESDIS IS A MEMBER OF 12 PLANET....
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SSD/SAB WEB ADDRESS FOR PRECIP ESTIMATES:
HTTP://WWW.SSD.NOAA.GOV/PS/PCPN/
...ALL LOWER CASE EXCEPT /PS/PCPN/
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LAT...LON 3851 12085 3825 11942 3328 11651 3244 11923 3518 12145
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