000
AXPZ20 KNHC 102101
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
2205 UTC FRI MAY 10 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 EXTENDS FROM 09N85W TO 10N93W WHERE LOW LEVEL 
WINDS SUGGEST A TRANSITION TO ITCZ WHICH EXTENDS TO 12N103W TO 
10N110W TO 07N125W TO BEYOND 07N140W. SCATTERED MODERATE TO 
ISOLATED STRONG CONVECTION WAS NOTED N OF 06N BETWEEN 81W AD 
85W. SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED 
WITHIN 90 NM N OF AXIS BETWEEN 105W AND 111W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION WAS NOTED WITHIN 60 NM N OF AXIS 
BETWEEN 125W AND 130W. SCATTERED MODERATE CONVECTION WAS 
NOTED WITHIN 60 NM N OF AXIS W OF 130W.

...DISCUSSION...

HIGH PRES 1028 MB IS CENTERED N OF THE AREA NEAR 34N127W. THE 
PRESSURE GRADIENT BETWEEN THE HIGH PRESSURE AREA AND LOWER 
PRESSURE IN THE VICINITY OF THE ITCZ IS MAINTAINING MODERATE TO 
FRESH TRADES N OF THE ITCZ TO 20N AND W OF 120W. OTHERWISE 
MAINLY GENTLE TO MODERATE WINDS PREVAIL ACROSS THE FORECAST 
AREA. WITH WINDS GENERALLY 20 KT OR LESS...AND NO SIGNIFICANT 
SWELL MOVING THROUGH THE AREA...SEAS REMAIN BELOW 8 FT...AND 
WILL CONTINUE TO REMAIN BELOW 8 FT THROUGH AT LEAST SUN. A WEAK 
LATE SEASON FRONTAL BOUNDARY WILL REACH AS FAR AS 30N140W LATE 
SAT BEFORE BECOMING DIFFUSE AND LIFTING NE. THE SURFACE HIGH 
PRESSURE AND ASSOCIATED RIDGE WILL WEAKEN SAT INTO SUN AS THIS 
BOUNDARY APPROACHES...THEN BECOME ABSORBED INTO A STRONGER RIDGE 
BUILDING BEHIND THE FRONT. 

A TROUGH IN THE SW CARIBBEAN WILL MOVE ACROSS CENTRAL AMERICA 
THIS WEEKEND. GAP WIND FLOW ASSOCIATED WITH THIS FEATURE WILL 
INTERACT WITH THE MONSOON TROUGH TO HELP INCREASE LOW LEVEL 
VORTICITY WITHIN THE MONSOON TROUGH. GAP WINDS THROUGH THE GULF 
OF TEHUANTEPEC WILL BE INDUCED MON AND TUE BY THE TROUGH AS IT 
SHIFTS FARTHER WEST. THIS WILL FURTHER INCREASE LOW LEVEL 
VORTICITY WITHIN THE MONSOON TROUGH TUE AND WED. IT IS LIKELY A 
LOW WILL DEVELOP ALONG THE MONSOON TROUGH AS A RESULT OF THESE 
INTERACTIONS...BUT THERE IS STILL A LOT OF UNCERTAINTY TO THE 
STRENGTH OF THE LOW. 
  
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AL