000
AXPZ20 KNHC 131552
TWDEP 

TROPICAL WEATHER DISCUSSION     
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC TUE MAR 13 2007

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W. THE FOLLOWING INFORMATION IS 
BASED ON SATELLITE IMAGERY...WEATHER OBSERVATIONS...RADAR...AND 
METEOROLOGICAL ANALYSIS.

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1545 UTC.

...ITCZ...

ITCZ AXIS IS CENTERED ALONG AXIS 3N77W 6N86W 3N103W 4N140W. 
SCATTERED MODERATE ISOLATED STRONG WITHIN 30 NM OF 6N77W AND 
5N90W AND WITHIN 15 NM EITHER SIDE OF LINE 2N103W 4N114W.

...DISCUSSION...

A MID TO UPPER LEVEL ANTICYCLONE IS NEAR 25N29W. AN UPPER 
CYCLONE IS CENTERED AT 26N137W WITH A TROUGH S TO A BASE NEAR 
13N135W. DRY UPPER AIR WRAPS AROUND THE W SEMICIRCLE OF THE 
CYCLONE AND IS ALSO NOTED WITHIN 240 NM W OF THE TROUGH AXIS. A 
BAND OF UPPER MOISTURE IS TRAPPED OVER THE E SEMICIRCLE OF THE 
CYCLONE ROUGHLY WITHIN 90 NM EITHER SIDE OF LINE 31N136W 
23N133W. FURTHER E...A LARGE DEEP LAYERED CYCLONE IS CENTERED 
NEAR 33N104W WITH ITS ENVELOPE OF CYCLONIC CIRCULATION 
DOMINATING THE DISCUSSION AREA N OF 21N BETWEEN 113W AND 100W.
OTHERWISE...DRY UPPER AIR IS INDICATED N OF 15N W OF 117W.

A QUASI STATIONARY UPPER ANTICYCLONE WELL E OF THE AREA NEAR 
4N58W REMAINS THE DOMINATE FEATURE WITH A RIDGE EXTENDING W 
ACROSS CENTRAL AMERICA TO NEAR 10N100W. A MOISTURE PLUME... 
ORIGINATING FROM ITCZ CONVECTION BETWEEN 95W AND 137W...IS 
NOTED WITHIN 360 NM EITHER SIDE OF LINE FROM 10N107W TO 
23N91W...THEN THE PLUME NARROWS AS IT TURNS E IN UPPER ZONAL 
FLOW AND EVAPORATES OVER THE EASTERN GULF OF MEXICO. 

AN INVERTED UPPER TROUGH IS NOTED OVER THE TROPICAL E PAC S OF 
7N ALONG 82W. A SMALL UPPER ANTICYCLONE IS NOTED NEAR 9N91W. 
OVERALL...THE UPPER FLOW IS DIFFLUENT S OF 7N E OF 95W WITH 
SLIGHT ENHANCEMENT OF THE NORTHERN HEMISPHERE ITCZ.

AT THE LOW LEVELS...SURFACE HIGH PRES IS CENTERED NEAR 27N120W 
1016 MB WITH BROAD HIGH PRES DOMINATING THE DISCUSSION AREA N OF 
THE ITCZ.

GAP WINDS...GULF OF TEHUANTEPEC...N-NE WINDS 20 WILL DIMINISH TO 
BELOW 20 KT LATE WED. NE WINDS 20 TO 25 KT CONTINUE IN AND 
DOWNSTREAM OF THE GULF OF PAPAGAYO AND EXTEND N TO INCLUDE MOST 
OF THE AREA DOWNWIND OF THE GULF OF FONSECA...WITH LITTLE CHANGE 
EXPECTED FOR AT LEAST 48 HOURS WITH MODELS HINTING AT SURGES TO 
30 KT. NLY WINDS TO 20 KT IN THE GULF OF PANAMA. 

$$
NELSON