000
AXPZ20 KNHC 290240
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI JUN 29 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 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0045 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH AXIS EXTENDS FROM THE SW CARIBBEAN ALONG 10N 
INLAND TO 11N84W TO 14N89W. THE ITCZ AXIS EXTENDS FROM 12N113W 
TO 07N140W. SCATTERED MODERATE TO STRONG CONVECTION LIES N OF 
07N E OF 85W INCLUDING OVER PANAMA AND COSTA RICA. SCATTERED 
MODERATE CONVECTION CAN BE FOUND WITHIN 120 NM EITHER SIDE OF 
THE AXIS W OF 130W. 
 
...DISCUSSION...

A QUIET PATTERN IS IN PLACE OVER THE FORECAST AREA. SIGNIFICANT 
CONVECTION IS PRIMARILY CONFINED OVER AND NEAR PANAMA/COSTA RICA 
WHERE THE MID LEVEL REMNANTS OF THE TROPICAL WAVE THAT PASSED 
THROUGH THE WESTERN CARIBBEAN YESTERDAY ARE MOVING INTO THE 
PACIFIC. THE SCATTERED MODERATE TO STRONG CONVECTION HERE 
DESCRIBED IN THE SECTION ABOVE CUTS OFF N OF THE COSTA 
RICA/NICARAGUA BORDER WHERE 45 KT EASTERLY FLOW ALOFT IS 
INHIBITING DEEP CONVECTION. ENHANCED LOW-LEVEL EASTERLY FLOW 
BEHIND THIS WAVE WILL FUNNEL THROUGH THE GULF OF PAPAGAYO...WITH 
THE ONSET OF FRESH WINDS EXPECTED FRI MORNING. FRESH WINDS ARE 
EXPECTED TO PERSIST DOWNWIND OF PAPAGAYO THROUGH THE END OF THE 
FORECAST PERIOD SAT EVENING. THIS WAVE MAY ONCE AGAIN BE 
TRACKABLE AT THE SURFACE LATE IN THE FORECAST PERIOD. SOME OF 
THE NUMERICAL GUIDANCE SUGGEST A SURFACE LOW WILL DEVELOP FROM 
THIS ENERGY EARLY NEXT WEEK. 

SCATTERED MODERATE CONVECTION CAN BE FOUND ALONG THE ITCZ W OF 
130W WHERE LIGHT...BROADLY DIFFUSE UPPER LEVEL WINDS ARE 
ENCOURAGING LIFT OF THE LOW TO MID-LEVEL MOSITURE POOLED ALONG 
THE ITCZ. THE 1834 UTC ASCAT PASS SHOWS THIS CONVECTION 
COINCIDES WITH A NARROW BAND OF FRESH TRADES JUST N OF THE ITCZ. 
THE SUBTROPICAL RIDGE TO THE N IS RELATIVELY WEAK...STEMMING 
FROM HIGH PRES WELL NW OF THE AREA NEAR 35N167W. THE RIDGE WILL 
WEAKEN FURTHER OVER THE NEXT FEW DAYS AS A DISSIPATING COLD 
FRONT MOVES INTO NW WATERS OVERNIGHT FRI NIGHT. FRESH TRADES 
WILL SHIFT W OF THE AREA BY SAT AS A RESULT. NO SIGNIFICANT 
WEATHER OR SEAS OVER 8 FT ARE EXPECTED WITH THIS DISSIPATING 
FRONT. HIGH PRES E OF THE FRONT WILL JOG SLIGHTLY CLOSER TO 
SHORE AS THE FRONT APPROACHES. THIS WILL INCREASE THE PRESSURE 
GRADIENT ALONG THE W COAST OF BAJA CALIFORNIA NORTE JUST ENOUGH 
TO INDUCE FRESH NW FLOW BEGINNING FRI EVENING AND EXPANDING WEST 
TO 120W AND SOUTHWARD ALONG THE PENINSULA TO 26N BY SAT EVENING. 

$$
SCHAUER