000
AXPZ20 KNHC 020903
TWDEP 

TROPICAL WEATHER DISCUSSION  
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC WED MAR 02 2011

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

BASED ON 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0715 UTC.

...ITCZ...

THE INTERTROPICAL CONVERGENCE ZONE AXIS IS ANALYZED FROM 07N77W 
TO 02N101W TO 04N107W TO 08N129W TO 06N140W. ISOLATED MODERATE 
CONVECTION LIES WITHIN 150 NM EITHER SIDE OF THE ITCZ AXIS E OF 
89W.

...DISCUSSION...

AN EXPANSIVE ANTICYCLONE ALOFT CENTERED NEAR 15N100W IS 
ASSOCIATED WITH AN AREA OF SUBSIDENCE AND DRY AIR IN THE MID TO 
UPPER LEVELS OVER MUCH OF THE AREA BETWEEN 10N AND 23N E OF 
115W. BROAD DIFFLUENT FLOW ALOFT BETWEEN THIS ANTICYCLONE AND 
ANOTHER S OF THE EQUATOR NEAR 15S95W IS ENHANCING VERTICAL 
MOTION NEAR THE ITCZ E OF 90W. CONVECTION THERE IS DESCRIBED IN 
THE ITCZ SECTION ABOVE AND SCATTERED MODERATE CONVECTION CAN 
ALSO BE FOUND WITHIN 60 NM OF THE COAST OF COLOMBIA FROM 03N TO 
04N. A WEAK UPPER LOW LIES NEAR 05N98W. THIS LOW IS FORECAST TO 
MOVE EASTWARD AND HELP BREAKDOWN THE ANTICYCLONE TO THE N OVER 
THE NEXT FEW DAYS.

A LINGERING UPPER LEVEL TROUGH LIES FROM 25N125W TO 14N132W TO 
10N140W WHILE A WEAKER NEGATIVELY TILTED UPPER TROUGH LIES FROM 
08N126W TO 04N110W. A BROAD AREA OF 50-70 KT SW WINDS LIES E OF 
THE MAIN TROUGH AND N OF THE NEGATIVELY TILTED TROUGH AND IS 
TRANSPORTING MID TO UPPER LEVEL MOSITURE NORTHWARD FROM THE 
TROPICS WITH MULTIPLE CLOUD LAYERS NOTED PRIMARILY N OF THE ITCZ 
TO 20N BETWEEN 120W AND 130W. DEEP LAYER TROUGHING LIES OVER NW 
WATERS AND THE ATTENDANT COLD FRONT WAS ANALYZED FROM 30N128W TO 
27N132W TO 21N140W. THE FRONT WILL SLOWLY MOVE EASTWARD TODAY 
WITH FRESH SOUTHERLY WINDS REMAINING AHEAD OF THE FRONT OVER N 
WATERS BETWEEN IT AND HIGH PRES TO ITS E THROUGH THIS AFTERNOON. 
THE FRONT WILL DISSIPATE AND WINDS WILL DIMINISH BELOW ADVISORY 
CRITERIA BY THU MORNING.

BROAD SURFACE RIDGING CURRENTLY DOMINATES PACIFIC FORECAST 
WATERS E OF THE FRONT TO 105W N OF 15N. THE PRES GRADIENT 
BETWEEN THIS RIDGING AND LOWER PRES ASSOCIATED WITH THE ITCZ IS 
PRODUCING AN AREA OF FRESH TRADE WINDS PRIMARILY FROM 08N TO 12N 
BETWEEN 115W AND 135W. THESE TRADES WILL MIGRATE WESTWARD AND 
EXPAND NORTHWARD AS THE HIGH PRES CENTER TO THE N MERGES WITH 
HIGH PRES BEHIND THE COLD FRONT OVER THE NEXT TWO 
DAYS...ALLOWING A STRONGER HIGH TO BECOME ESTABLISHED FARTHER W. 

GULF OF CALIFORNIA...HIGH PRES LIES ON BOTH THE E SIDE OF THE 
GULF OF CALIFORNIA BEHIND A STATIONARY FRONT CURRENTLY OVER THE 
CENTRAL GULF OF MEXICO AS WELL ON THE W SIDE WHERE THE PACIFIC 
HIGH LIES AHEAD OF THE COLD FRONT APPROACHING FROM NW WATERS. 
THE 0108Z WINDSAT PASS CONFIRMED FRESH NW TO N WINDS IN THE GULF 
OF CALIFORNIA S OF 28N. BY THIS EVENING...NW WINDS WILL INCREASE 
TO 20 KT ON THE WESTERN SIDE OF THE BAJA PENINSULA AS THE MEAN 
SURFACE RIDGE...ALONG WITH THE STRONGEST PRES GRADIENT...SHIFTS 
W. 

GULF OF TEHUANTEPEC...THE STATIONARY FRONT OVER THE CENTRAL GULF 
OF MEXICO CONTINUES TO SEND NORTHERLY WINDS THROUGH THE ISTHMUS 
OF TEHUANTEPEC...WITH WINDS BELIEVED TO STILL BE AT GALE FORCE 
IN THE GULF OF TEHUANTEPEC. GALE CONDITIONS WILL CONTINUE UNTIL 
JUST AFTER SUNRISE THIS MORNING...WITH WINDS DIMINISHING BELOW 
20 KT BY THU AFTERNOON. 

GULF OF PAPAGAYO...NE TO E WINDS WILL CONTINUE TO PULSE AT 15 TO 
20 KT ACCORDING TO THE 0250Z ASCAT PASS. WINDS WILL INCREASE TO 
20 TO 25 KT TODAY AS HIGH PRES BUILDS S OVER CENTRAL AMERICA 
BEHIND THE FRONT OVER THE GULF OF MEXICO.

GULF OF PANAMA...N WINDS TO 20 KT ARE EXPECTED IN THE GULF OF 
PANAMA BY THU MORNING AS HIGH PRES BUILDS S THROUGH CENTRAL 
AMERICA...INCREASING THE PRES GRADIENT BETWEEN IT AND LOW PRES 
OVER COLOMBIA.

$$
SCHAUER