000
AXPZ20 KNHC 082158
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC WED MAY 08 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 1800 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
2100 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
THE MONSOON TROUGH AXIS EXTENDS FROM 10N85W TO 07N91W WHERE LOW 
LEVEL WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO BEYOND 
06N140W. SCATTERED MODERATE CONVECTION WAS NOTED WITHIN 120 NM N 
OF AXIS BETWEEN 111W AND 126W.

...DISCUSSION...

RIDGE OF HIGH PRESSURE PREVAILS OVER THE N PART OF THE AREA 
ALONG 26N. LATEST OBSERVATIONS INDICATE MAINLY GENTLE WINDS 
PREVAIL OVER THE FORECAST AREA...EXCEPT N OF THE ITCZ W OF 130W 
WHERE THE PRESSURE GRADIENT IS LOCALLY TIGHTER AND MODERATE TO 
FRESH TRADES PREVAIL. SEAS REMAIN BELOW 8 FT OVER THE FORECAST 
AREA. THE RIDGE WILL CONTINUE TO BUILD OVER THE NEXT 48 HOURS 
WHICH WILL INCREASE COVERAGE OF THE MODERATE TO FRESH TRADES 
OVER THE W PART OF THE AREA N OF THE ITCZ. THE LARGER COVERAGE 
OF FRESH TRADES WILL INCREASE SEAS TO 8 FT OVER THIS AREA THU 
AND FRI.  

LOOKING AHEAD...A COMPLEX SYNOPTIC SITUATION HAS HELPED DEVELOP 
A CARIBBEAN WAVE/TROUGH IN THE CENTRAL CARIBBEAN WATERS. 
FORECAST MODELS ARE CURRENTLY DEPICTING AN INTERESTING SCENARIO 
TO FOLLOW OVER THE NEXT WEEK. THE KEY FEATURE TO WATCH IS THE 
WAVE/TROUGH...HOWEVER OTHER KEY VARIABLES INCLUDE THE MONSOON 
TROUGH IN THE E PACIFIC...AND GAP WIND FLOW THROUGH THE 
TOPOGRAPHY OF CENTRAL AMERICA INTO THE GULFS OF PAPAGAYO AND 
TEHUANTEPEC INDUCED BY THE WAVE/TROUGH. THE LATEST SCENARIO 
DEPICTED BY MODEL GUIDANCE HAS THE WAVE/TROUGH IN THE CARIBBEAN 
SHIFTING WESTWARD ACROSS CENTRAL AMERICA INTO THE FAR E PACIFIC 
THIS WEEKEND. GAP WINDS THROUGH THE GULF OF PAPAGAYO ASSOCIATED 
WITH THE WAVE/TROUGH WILL INTERACT WITH THE MONSOON TROUGH AND 
HELP TO INCREASE LOW LEVEL VORTICITY WITHIN THE MONSOON TROUGH 
LATE THIS WEEKEND. GAP WINDS THROUGH THE GULF OF TEHUANTEPEC 
WILL BE INDUCED EARLY NEXT WEEK BY THE WAVE/TROUGH AS IT SHIFTS 
WESTWARD ACROSS THE FAR E PORTION OF THE NE PACIFIC WATERS. THIS 
GAP WIND EVENT WILL HELP FURTHER INCREASE LOW LEVEL VORTICITY 
WITHIN THE MONSOON TROUGH EARLY NEXT WEEK. LATEST MODEL GUIDANCE 
ALSO SUGGESTS THAT THE BACKGROUND ENVIRONMENT WILL BECOME MORE 
FAVORABLE FOR BAROTROPIC GROWTH OF THE DISTURBANCE WITHIN THE 
MONSOON TROUGH EARLY NEXT WEEK. THIS SCENARIO DOES EXTEND 
SEVERAL DAYS INTO THE FUTURE...AND CAN CERTAINLY CHANGE DURING 
THAT TIME. HOWEVER...IT WILL BE INTERESTING TO WATCH OVER THE 
NEXT SEVERAL DAYS. 
  
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AL