000
AXPZ20 KNHC 032142
TWDEP 

TROPICAL WEATHER DISCUSSION   
NWS NATIONAL HURRICANE CENTER MIAMI FL
2205 UTC TUE MAY 03 2011

TROPICAL WEATHER DISCUSSION FOR THE EASTERN PACIFIC OCEAN FROM 
THE EQUATOR TO 32N...EAST OF 140W.

BASED ON 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2045 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED ALONG 06N77W 
TO 07N105W TO 06N120W TO 03N140W. SCATTERED MODERATE TO STRONG 
CONVECTION IS FROM 04N TO 08N E OF 80W. SCATTERED MODERATE 
CONVECTION IS FROM 03N TO 12N BETWEEN 100W AN 113W. SCATTERED 
MODERATE TO ISOLATED STRONG CONVECTION IS FROM 02N TO 07N 
BETWEEN 118W AND 130W...AND FROM 01N TO 04N BETWEEN 132W AND 
140W.

...DISCUSSION...
AN UPPER LEVEL CYCLONE IS FILLING NEAR 28N131W WITH A NEGATIVE 
TILT TROUGH AXIS EXTENDING SE THROUGH ANOTHER CYCLONIC 
CIRCULATION NEAR 21N122W TO A BASE NEAR 06N107W. MIDDLE TO UPPER 
LEVEL MOISTURE IS NOTED WITHIN 480 NM NE OF THE TROUGH AXIS 
SPILLING OVER MOST OF THE GULF OF CALIFORNIA AND MEXICO. WATER 
VAPOR IMAGERY INDICATES FAIRLY DRY CONDITIONS ON THE BACK SIDE 
OF THE TROUGH FROM 08N TO 22N BETWEEN 115W AND 130W. AN UPPER 
LEVEL ANTICYCLONE IS CENTERED NEAR THE ISTHMUS OF TEHUANTEPEC...
14N95W WITH A RIDGE EXTENDING TO THE NW AND CRESTING NEAR 
30N122W. UPPER LEVEL DIFFLUENCE BETWEEN THE UPPER TROUGH AND 
THIS RIDGE IS ENHANCING ISOLATED MODERATE CONVECTION IN THE DEEP 
TROPICS S OF 12N BETWEEN 103W AND 111W. THIS SYNOPTIC PATTERN 
SHOULD SHIFT SLIGHTLY NORTHEASTWARD OVER THE NEXT 24 HOURS. THE 
UPPER LEVELS APPEAR VERY DRY ELSEWHERE S OF 17N E OF 100W.

AT THE LOW LEVELS...FLOW IS DOMINATED BY A 1039 MB SURFACE HIGH 
NORTH OF OUR AREA NEAR 43N132W WITH A MODERATE GRADIENT ON 
THE EQUATORWARD SIDE CAUSING 20 KT NE TRADEWINDS MAINLY W OF 
120W. ACCOMPANYING THIS ARE HIGH SEAS OF UP TO 10 FT IN MIXED NE 
WIND WAVES AND NW SWELL. IN 48 HOURS...THE GRADIENT WEAKENS AND 
A LARGE PORTION OF THE 20 KT NE TRADEWINDS WILL LOCATE W OF 
140W...HOWEVER A SMALL AREA FROM 13N TO 26N W OF 135W WILL 
CONTINUE AND PROVIDE SEAS TO 8 FT.

GULF OF CALIFORNIA...A TIGHT PRESSURE GRADIENT OVER NW MEXICO IS 
SUPPORTING NW WINDS IN THE RANGE OF 20 TO 25 KT N OF 24N. AN 
ASCAT PASS FROM AROUND 03/0452 UTC SHOWED A SMALL SWATH OF 25 TO 
30 KT WINDS IN THE VICINITY OF 26N111W. ALL NWP MODELS SUGGEST 
THE WINDS HAVE ALREADY PEAKED AND ARE FORECAST TO DROP BELOW 20 
KT TONIGHT. 
   
GULF OF PAPAGAYO...NE TO E WINDS AT 20 TO 25 KT WILL CONTINUE TO 
PULSE THROUGH THURSDAY IN THE AREA FROM 10N TO 12N E OF 90W.  
WINDS AND SEAS HIGHEST LATE NIGHT AND EARLY MORNING HOURS.

GULF OF TEHUANTEPEC...GALE FORCE WINDS ARE NOW OVER THE GULF OF 
TEHUANTEPEC. THIS GAP WIND EVENT IS EXPECTED TO PEAK TONIGHT AND 
EARLY WEDNESDAY MORNING. THE FORECAST WINDS OF 35 TO 45 KT 
WOULD MAKE THIS GAP WIND EVENT THE STRONGEST FOR THE MONTH OF 
MAY IN THE PERIOD BEGINNING IN 1999. 

$$
FORMOSA