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SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 09/21/07 1815Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678
LATEST DATA USED: GOES-WEST:1800Z  JS
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LOCATION...SOUTHERN NEVADA/SOUTHEASTERN CALIFORNIA
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ATTN WFOS...PSR...VEF...SGX...
ATTN RFCS...CBRFC...CNRFC...
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EVENT...WARM TOP TRAINING CONVECTION ACROSS SE CA/S NV.
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SATELLITE ANALYSIS AND TRENDS...CERTAINLY NOT MUCH SATELLITE ENHANCEMENT
WITH BAND PRIMARILY AFFECTING SE CA COUNTIES OF IMPERIAL/RIVERSIDE/SAN
BERNARDINO. HOWEVER WARMER RAIN PROCESSES WITH RELATIVELY LOWER
EQUILIBRIUM LEVELS PRESENT ALONG WITH NARROW CONVERGENT FOCUS WITHIN
BAND LIKELY ARE CONTRIBUTING TO MORE EFFICIENT RAIN PRODUCING CELLS
THAN WHAT SATELLITE IMAGERY WOULD SUGGEST. THIS IS ALSO SUPPORTED BY
SPOTTER REPORT IN SAN BERNARDINO COUNTY AS PER RECENT FLOOD ADVISORY
(FLS) ISSUED BY LAS VEGAS. ACTIVITY IS ALSO ALONG EDGE OF MOISTURE
GRADIENT WITH SW AND S MID/UPPER LEVEL FLOW INTO THE BAND LIKELY NOW
TAPPING INTO HIGHER MOISTURE JUST TO THE SOUTH. GOES SOUNDER DATA ALONG
WITH GPS DATA INDICATE PW VALUES HAVE CREPT UP INTO THE 1.0-1.25" RANGE
IN THE VICINITY OF THE BAND. THIS SHOULD BE ENOUGH TO SUPPORT GENERAL
.5"-1.0"/HR RAIN RATES WITH THE CONVECTIVE CELLS WITHIN THE BAND AND
LOCALIZED RATES TO 1.0-1.25"/HR WITH THE STRONGEST CORES. LATEST TRENDS
INDICATE THE BAND IS PIVOTING WITH THE NORTHERN PORTION MOVING TO THE
WEST WHILE THE SOUTHERN END REMAINS NEARLY STATIONARY WITH A POSSIBLE
SLIGHT DRIFT TO THE EAST. THIS HAS RESULTED IN CELL TRAINING ACROSS
IMPERIAL/RIVERSIDE/SAN BERNARDINO COUNTIES WHICH SHOULD CONTINUE THE
HEAVY RAIN THREAT FOR AT LEAST THE NEXT 1-2 HOURS AS WATER VAPOR IMAGERY
SHOWS LITTLE MOVEMENT TO THE UPPER LOW OFF THE S CA COAST. IF ANYTHING
THE LOW HAS RETROGRADED A BIT FARTHER TO THE WEST DURING THE MORNING.
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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 3570 11534 3159 11488 3157 11634 3557 11686
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