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SATELLITE PRECIPITATION ESTIMATES..DATE/TIME 12/20/07 1549Z
SATELLITE ANALYSIS BRANCH/NESDIS---NPPU---TEL.301-763-8678
LATEST DATA USED: G12  1530Z  CK
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LOCATION...LOUISIANA..MISSISSIPPI..ALABAMA..W FL PANHANDLE
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ATTN WFOS...MOB...JAN...LIX...LCH...
ATTN RFCS...SERFC...LMRFC...
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EVENT...MERGER OF CONVECTION LIKELY OVER S/SE LA..WITH HVY RAIN TO SPREAD
EWD ACRS DISCUSSION AREA
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SATELLITE ANALYSIS AND TRENDS...ATTM IMAGERY SHOWS TWO DISTINCT AREAS
OF CNVTN. ONE IS A SW-NE BAND EXTENDING FM UPPR TX COAST THRU SW MS TO
W TN. A SECOND AREA HAS BEEN INCRG OVER S LA AND N GULFMEX. BOTH AREAS
ARE PROGRESSING E..WITH NE EXPANSION OF SRN CONVECTIVE AREA.
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WV IMAGERY ANIMATION SHOWS UPPR TROF OVER SRN PLAINS IS MOVG EWD..WITH
VORT/VORT LOBE OVER E CENTRAL OK/NE TX. STRONG SUBTROPICAL JET EXTENDS
ALONG BASE OF TROF..WITH JET STREAK..PER GOES STLT WINDS..INTERSECTING
CNVTN ALONG UPPR TX COAST AND GULFMEX/S LA. ALTHOUGH TROF AND CNVTN
IS PROGRESSIVE..STLT TRENDS INDICATE THAT THE TWO AREAS OF CNVTN WILL
MERGE OVER LA AND SW MS. WITH THIS MERGER..AND THE APPROACH OF THE
TROF..WOULD EXPECT FURTHER INTENSIFICATION OF CNVTN DURING THE MORNING.
FURTHER SUPPORTING THIS IS LL SW-NE THETA-E RIDGE EXTENDING W GULFMEX
NEWD THRU LA/MS..ALONG WITH THETA-E ADVECTION FM S LA THRU S HALF OF
MS. OBJECTIVE ANALYSIS OF 15Z SFC DATA SHOWS SFC CONVERGENCE MAX EXTENDING
FM GENERAL VCNTY OF LFT TO S OF JAN. THUS..MUCH SUPPORT FOR EXPANSION
AND EWD MOVEMENT/SPREAD OF HVY RAIN. AS FOR LL MOISTURE..DEW POINTS RANGE
UP TO THE MID 60'S..AND PW'S PER MICROWAVE IMAGERY RANGE UP TO 1.5-1.6"
NR/S OF LA COAST. ACCORDING TO CIRA EXPERIMENTAL PW PRODUCT..PW'S IN
THE AREA RANGE CLOSE TO 200 PER CENT OF NORMAL. THUS..DESPITE OVERALL
MOVEMENT OF CNVTN..MERGERS COMBINED WITH COPIOUS LL MOISTURE WILL RESULT
IN HVY DOWNPOURS IN SHORT PERIODS OF TIME. WITH EQUILIBRIUM LVLS ON THE
LOW SIDE..CNVCTV CLOUD TOPS WILL TEND TO REMAIN WARM TOP VARIETY FOR THE
MOST PART THIS MORNING..BUT STILL PRODUCE HVY DOWNPOURS. HOWEVER..CLOUD
TOPS SHOULD BEGIN TO REACH COLDER LEVELS AS MERGERS OCCUR. WITH THE
STEADY EWD MOVEMENT OF THE SHORT WAVE WOULD EXPECT HVY RAIN TO SPREAD
INTO THE W FL PANHANDLE DURING THE AFTN HOURS.
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WITH THE MERGER AND EXPANSION OF THE TWO CONVECTIVE AREAS MENTIONED
ABOVE..THERE IS THE POSSIBILITY OF SOME CELL TRAINING ACRS PARTS
OF THE AREA FM S CENTRAL/S LA THRU S MS..AND EVENTUALLY S AL/W FL
PANHANDLE.. WHICH WOULD RESULT IN HVY RAINFALL TOTALS IN ADDITION TO
HVY RAINBURSTS IN SHORT PERIODS OF TIME.
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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 3166 8766 2875 8678 2910 9356 3010 9290 3162 9095
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