000
AXPZ20 KNHC 281525
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1605 UTC THU JUN 28 2012

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 EXTENDS FROM THE BORDER OF PANAMA AND COLOMBIA
NEAR 07N78W TO 06N86W TO 13N102W TO 10N113W TO 10N123W. THE ITCZ 
AXIS EXTENDS FROM 10N123W TO 09N130W TO BEYOND 06N140W. SCATTERED
MODERATE TO STRONG CONVECTION IS IN THE GULF OF PANAMA N OF 05N 
E OF 80W. SCATTERED MODERATE TO STRONG CONVECTION IS WITHIN 60 
NM OF 10N99W. SCATTERED MODERATE CONVECTION IS WITHIN 45 NM OF 
THE ITCZ AXIS W OF 129W. 
 
...DISCUSSION...
A DISSIPATING COLD FRONT MOVING INTO EXTREME NW PORTION OF THE 
DISCUSSION AREA WILL WEAKEN INTO A TROUGH LATER TODAY. A WEAK 
PRES GRADIENT EXISTS ACROSS THE ENTIRE REGION...CHARACTERIZED BY 
A BROAD LOW PRES TROUGH S OF 10N-15N AND A WEAK RIDGE N OF 20N W 
OF NORTH AMERICA. THE CURRENT SYNOPTIC PATTERN IS CONDUCIVE TO 
LIGHT WINDS AND BENIGN MARINE CONDITIONS WITH SEAS 5 FT OR LESS.
LITTLE CHANGE IS EXPECTED THROUGH SAT MORNING. A COLD FRONT N OF 
THE AREA WILL WEAKEN AS IT PUSHES S TOWARDS 30N THROUGH SAT... 
AND MAINTAIN A VERY WEAK PRES GRADIENT OVER THE ENTIRE DISCUSSION
AREA. A HIGH PRES RIDGE WILL SLOWLY BUILD WESTWARD ALONG 25N-30N 
SUN THROUGH TUE...ALLOWING MODERATE TRADE WINDS TO REDEVELOP S OF
20N EARLY NEXT WEEK.

A DIFFUSE TROPICAL WAVE ALONG 79W IN THE CARIBBEAN WILL MOVE W 
ACROSS CENTRAL AMERICA THROUGH SAT...AND INDUCE FRESH EASTERLY 
WINDS THROUGH THE GULF OF PAPAGAYO FROM 10N-12N E OF 91W THIS 
WEEKEND...ENHANCING CYCLONIC VORTICITY S OF THE SURGE IN EASTERLY
WINDS...AND IS EXPECTED TO PINCH OFF A TROPICAL LOW NEAR 09N90W 
ON SAT THAT WILL MOVE W TO AROUND 10N95W BY SUN. THE GFS MODEL 
DOES NOT INTENSIFY THIS LOW BEYOND 15-20 KT...BUT THE ECMWF AND 
UKMET GLOBAL MODELS ARE A LITTLE MORE AGGRESSIVE. NONE OF THE 
GLOBAL MODELS SHOW TROPICAL CYCLONE GENESIS THROUGH MON.

$$
MUNDELL