000
AXPZ20 KNHC 271532
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC WED MAR 27 2013

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 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...           

THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 05N90W. THE ITCZ 
AXIS EXTENDS FROM 04N92W TO 0.5N110W TO 02N123W. SCATTERED 
MODERATE CONVECTION IS WITHIN 90 NM N OF THE ITCZ BETWEEN 118W 
AND 121W. ADDITIONALLY...SCATTERED MODERATE TO STRONG 
CONVECTION IS FROM 03N TO 05N BETWEEN 83W AND 86W.

...DISCUSSION...

STRONG SURFACE HIGH PRESSURE EXTENDS FROM THE TEXAS HILL COUNTRY 
S TO THE MEXICAN GULF OF MEXICO COAST WITH AN ASSOCIATED TIGHT 
PRESSURE GRADIENT JUST INLAND OVER SE MEXICO AND THE ISTHMUS OF 
TEHUANTEPEC. AS A RESULT...N WINDS ARE SURGING THROUGH THE 
CHIVELA PASS INTO AND DOWNSTREAM OF THE GULF OF TEHUANTEPEC AT 
30 TO 45 KT. A CARNIVAL CRUISE SHIP RIGHT IN THE GULF OF 
TEHUANTEPEC REPORTED 19 FT SEAS AT 12 UTC. THE LATEST SEA 
SURFACE TEMPERATURE ANALYSIS SHOWS A COLD TONGUE OF TEMPERATURES 
DUE TO THE ONGOING UPWELLING FROM THE GALE FORCE WINDS. THE 
PRESSURE GRADIENT WILL BEGIN TO RELAX THROUGH THE DAY TODAY 
ALLOWING FOR WINDS TO DIMINISH TO MINIMAL GALE...PERSISTING 
THROUGH DAYBREAK THU. WINDS WILL THEN QUICKLY DIMINISH TO 20 TO 
25 KT THU AFTERNOON. WINDS MAY BRIEFLY FURTHER DIMINISH TO 10 TO 
20 KT THU EVENING...ALTHOUGH ANOTHER NORTHERLY SURGE OF 20 TO 25 
KT WINDS IS EXPECTED LATE THU NIGHT INTO FRI MORNING.

IN THE GULF OF PAPAGAYO...NE TO E WINDS AT 20 TO 25 KT ALONG 
WITH SEAS OF 8 TO 9 FT ARE OCCURRING DOWNWIND TO 09N91W. EXPECT 
THESE WINDS TO INCREASE TO 20 TO 30 KT OVERNIGHT TONIGHT INTO 
EARLY THU AS A DISSIPATING COLD FRONT MOVES BY THROUGH NICARAGUA 
TO COSTA RICA BEFORE LOOSING ALL FRONTAL DEFINITION...WITH A 
TIGHT PRES GRADIENT OVER EASTERN CENTRAL AMERICA IN THE FRONTS 
WAKE. THIS INCREASE IN WINDS WILL BUILDS SEAS TO UP TO 11 FT IN 
THE GULF OF PAPAGAYO AREA...WITH 20 TO 25 KT WINDS EVEN 
EXTENDING ALL THE WAY TO 100W BY THU MORNING. ALSO...SEAS OF 8 
TO 10 FT IN MIXED LONG PERIOD NW SWELL...AND SHORTER PERIOD NE 
SWELL GENERATED IN BOTH THE GULFS OF TEHUANTEPEC AND PAPAGAYO 
WILL COVER THE WATERS FROM 04N TO 12N BETWEEN 92W AND 107W BY 
THU MORNING...PERSISTING THROUGH FRI MORNING WHILE EXPANDING 
SLIGHTLY WESTWARD TO 112W.

IN THE GULF OF PANAMA...NORTHERLY WINDS OF 15 TO 20 KT ARE 
EXPECTED TO PULSE THROUGH LATE FRI WITH BRIEF SURGES OF HIGHER 
SPEEDS POSSIBLY IN THE RANGE OF 20 TO 25 KT.

OUTSIDE OF THE NE PACIFIC GULFS...CURRENT MARINE CONDITIONS ARE 
FAIRLY BENIGN WITH A VERY WEAK AND BROAD PRESSURE PATTERN 
PRESENT AT THE SURFACE. OVERALL THIS PATTERN WILL NOT CHANGE 
MUCH THROUGH THE END OF THE WEEK...EXCEPT OVER THE FAR NW 
PORTION OF THE DISCUSSION WATERS WHERE A PRE-FRONTAL TROUGH HAS 
ALREADY MANAGED TO SNEAK INTO THE WATERS FROM 30N135W TO 
27N140W. THE ACTUAL COLD FRONT WILL MOVE INTO THE NW CORNER 
THU...REACHING FROM 30N133W TO 23N140W THU EVENING...THEN SLOWLY 
MOVING E EXTENDING FROM 30N132W TO 22N140W BY FRI MORNING. MOST 
OF THE ASSOCIATED ENERGY AND DISTURBED WEATHER WILL REMAIN N OF 
30N CLOSER TO A PARENT SURFACE LOW...HOWEVER DO EXPECT A BRIEF 
EPISODE OF W TO NW 20 TO 25 KT WINDS N OF 29N W OF THE FRONT THU 
EVENING...DIMINISHING BY FRI MORNING WITH LINGERING SEAS OF 8 TO 
9 FT IN NW SWELL N OF 29N W OF THE FRONT BY THEN.

$$
LEWITSKY