000
AXPZ20 KNHC 191543
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC FRI MAR 19 2010

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

BASED ON 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...ITCZ...
AXIS ALONG 02N79W TO 05N88W TO 02N98W TO 05.5N112W TO 01N126W TO 
02N140W. ISOLATED MODERATE CONVECTION WITHIN 240 NM N OF AXIS 
AND 90 NM S OF AXIS BETWEEN 90W AND 103W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WITHIN 240 NM N OF AXIS BETWEEN 108W 
AND 117W. SCATTERED MODERATE TO STRONG CONVECTION WITHIN 300 NM 
N OF AXIS AND 150 NM S OF AXIS BETWEEN 117W AND 128W.

...DISCUSSION...
A NEGATIVELY TILTED UPPER LEVEL TROUGH IS STARTING TO LIFT OUT N 
OF THE AREA. THE ASSOCIATED SURFACE COLD FRONT HAS ENTERED THE 
FAR NW PART OF THE AREA...BUT WITHOUT UPPER LEVEL SUPPORT WILL 
NOT PUSH VERY FAR INTO THE AREA BEFORE DISSIPATING. WITH THE 
TROUGH LIFTING OUT...ZONAL FLOW PREVAILS ACROSS MUCH OF THE 
UPPER LEVELS N OF 15N. UPPER LEVEL RIDGING PREVAILS ACROSS THE 
DEEP TROPICS. 

AT THE SURFACE...
A COLD FRONT HAS MOVED INTO THE FAR NW PART OF THE FORECAST 
AREA. SURFACE HIGH PRESSURE 1020 MB IS CENTERED NEAR 30N130W. 
THE PRESSURE GRADIENT BETWEEN THE HIGH AND LOCALLY LOWER 
PRESSURE IN THE CONVECTIVELY ACTIVE PORTION OF THE ITCZ IS 
PRODUCING 20 KT TRADES FROM 07N TO 13N BETWEEN 116W AND 130W. 
THE LOCALLY HIGHER TRADES ARE MAINTAINING MOISTURE CONVERGENCE 
AND ACTIVE CONVECTION IN THE ITCZ BETWEEN 117W AND 128W. 

NW SWELLS PREVAILING ACROSS THE AREA WILL CONTINUE TO GRADUALLY 
SUBSIDE. HOWEVER...ANOTHER SET OF LONG PERIOD NW SWELLS HAS 
ENTERED THE NW PART OF THE AREA...AND WILL PROPAGATE S AND E 
THROUGH THE FORECAST PERIOD.

GAP WINDS...
N TO NE WINDS OVER THE GULF OF TEHUANTEPEC WILL CONTINUE TO 
DIMINISH...FALLING BELOW 20 KT THIS EVENING. WINDS ARE EXPECTED 
TO INCREASE ONCE AGAIN...POSSIBLY TO GALE FORCE...ON SUNDAY. 

AS THE SURFACE COLD FRONT IN THE WESTERN CARIBBEAN HAS REACHED 
AS FAR E AS PANAMA...WINDS FUNNELING THROUGH THE CENTRAL AMERICA 
GAPS ARE HELPING FOR FRESH TO STRONG WINDS OVER THE GULF OF 
PAPAGAYO AND PANAMA. THE FRESH TO STRONG WINDS ARE EXPECTED TO 
CONTINUE ACROSS THE GULF OF PAPAGAYO THROUGH THE FORECAST 
PERIOD...AND WILL DIMINISH BELOW 20 KT OVER THE GULF OF PANAMA 
SAT. 

FOR ADDITIONAL INFORMATION PLEASE VISIT 
HTTP://WWW.HURRICANES.GOV/MARINE

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AL