000
AXPZ20 KNHC 281000
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH
0915 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
MONSOON TROUGH FROM 06N77W TO 05N88W TO 13N99W AND FROM LOW PRES 
1008 MB AT 17N104W TO 11N110W TO 10N120W THEN ITCZ TO 09N126W TO 
BEYOND 06N140W.  SCATTERED MODERATE TO STRONG CONVECTION FROM 
08N TO 12N BETWEEN 95W AND 98W.  ISOLATED MODERATE CONVECTION 
WITHIN 45 NM N OF AXIS W OF 130W. 
 
...DISCUSSION...
SHARP DEEP LAYER LONGWAVE TROUGH EXTEND SW ACROSS NW PORTION OF 
BASIN FROM WELL DEFINED CYCLONE AT 34N128W TO 32N130W TO BEYOND  
26N140W.  ELONGATED UPPER LEVEL ANTICYCLONE WITH A MEAN CENTER 
NEAR 26N117W HAS RIDGE EXTEND SW TO 17N140W.  BOTH FEATURE 
MANAGE TO MAINTAIN VERY DRY AIR MASS ACROSS MOST OF BASIN N OF 
10N W OF 110W CURTAILING ANY SIGNIFICANT DEEP CONVECTION UNDER 
THEIR COVERAGE.  INVERTED MID TO UPPER LEVEL TROUGH EXTEND FROM 
SOUTHERN TIP OF BAJA CALIFORNIA PENINSULA TO 12N115W SEPARATING 
ANTICYCLONE FROM SECOND ONE OVER WESTERN GULF OF MEXICO.  LATTER 
ANTICYCLONE MAINTAINS STEADY FLOW OF E-NE WINDS ALOFT ADVECTING 
ABUNDANT TROPICAL MOISTURE FROM SOUTH AMERICA INTO E PAC S OF 
16N E OF 110W.  AT THE SAME TIME...ASSOCIATED 40-45 KT WINDS 
ALOFT PROVIDE ADVERSE CAPPING ANY SIGNIFICANT VERTICAL 
DEVELOPMENT OF CLOUDS...COMPOUNDING THE LACK OF UPLIFT FOR DEEP 
CONVECTION.   

...ELSEWHERE AT LOWER LEVELS...
COLD FRONT ASSOCIATED WITH DEEP LAYER TROUGH APPROACHES NW 
CORNER OF BASIN BUT STALLS ALONG 29N-30N WHEN SUPPORTING UPPER 
LEVEL CYCLONE SHIFTS NE AND ALLOWS SURFACE RIDGE TO SPREAD W 
EFFECTIVELY DISSIPATING COLD FRONT.  ATTENDANT WINDS ARE NOT 
EXPECTED TO REACH ABOVE MODERATE BREEZE AND REMAIN BELOW 8 FT.   
   
STRONG TO NEAR GALE FORCE WINDS OVER SW CARIBBEAN ASSOCIATED 
WITH TROPICAL WAVE ALONG 78W EXPECTED TO ENHANCE MONSOON TROUGH 
OVER PANAMA WITH MODEL GUIDANCE POINTING AT WEAK LOW PRES 1010 
MB DEVELOPING NEAR COAST OF COSTA RICA FRI.  THIS COULD 
REINFORCE E WIND FLOW ACROSS NICARAGUA MOUNTAINS AND EMERGE AS 
FRESH BREEZE OVER GULF OF PAPAGAYO LATE FRI.  OTHERWISE...NO 
IMMEDIATE TROPICAL FEATURE EXPECTED WITHIN NEXT TWO DAYS.   

$$
WALLY BARNES