000
AXPZ20 KNHC 040245
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC WED JUL 04 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 
0300 UTC.

...SPECIAL FEATURE... 
LOW PRES CENTER 1006 MB AT 12N105W HAS SCATTERED MODERATE TO 
STRONG CONVECTION WITHIN 120 NM E QUADRANT OF LOW. THERE IS 
CURRENTLY A HIGH CHANCE THAT THIS SYSTEM WILL DEVELOP INTO A 
TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS. 

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS REMAINS SPLIT. ONE PART OF THE AXIS 
EXTENDS FROM 09N84W TO 08N91W TO 10N97W. THE OTHER PART OF THE 
AXIS IS ANCHORED TO LOW PRES MENTIONED ABOVE IN SPECIAL FEATURES 
CENTERED NEAR 12N105W 1006 MB THEN EXTENDS TO 11N110W TO 12N116W 
TO 07N131W THEN TRANSITIONS TO ITCZ AXIS TO BEYOND 05N140W. 
SCATTERED MODERATE TO STRONG CONVECTION WAS NOTED WITHIN 150 NM 
S OF AXIS BETWEEN 81W AND 86W. SCATTERED MODERATE TO STRONG 
CONVECTION WAS NOTED WITHIN 120 NM N OF AXIS BETWEEN 93W AND 
98W. SCATTERED MODERATE CONVERSION WAS NOTED WITHIN 90 NM N OF 
AXIS BETWEEN 117W AND 134W.

...DISCUSSION...

HIGH PRESSURE 1033 MB CENTERED NEAR 38N153W WITH RIDGE EXTENDING 
SE TO NEAR 25N116W. ASIDE FROM THE LOW PRESSURE CENTER MENTIONED 
IN THE SPECIAL FEATURES SECTION...CONDITIONS ARE RATHER BENIGN 
ACROSS THE REMAINDER OF THE FORECAST AREA. IN RESPONSE TO A 
TROPICAL WAVE OVER THE WESTERN CARIBBEAN WATERS...FRESH 20 KT 
WINDS ARE FUNNELING FROM THE SW CARIBBEAN ACROSS THE GULF OF 
PAPAGAYO INTO THE FAR E WATERS FROM 10N TO 12N E OF 90W. THESE 
WINDS WILL CONTINUE THROUGH THE NEXT 48 HOURS. LOOKING BEYOND 48 
HOURS...CURRENT MODEL GUIDANCE SUGGESTS THIS AREA MAY BE ONE OF 
INTEREST. BASED ON MODEL GUIDANCE...THE SW MONSOONAL FLOW WILL 
INCREASE AS THE TROPICAL WAVE GETS CLOSER TO CENTRAL AMERICA. 
THIS INCREASE IN MONSOONAL FLOW COMBINED WITH THE GAP WIND FLOW 
THROUGH PAPAGAYO WILL HELP INCREASE LOW LEVEL VORTICITY WITHIN 
THE MONSOON TROUGH...WITH BACKGROUND FLOW FAVORABLE FOR FURTHER 
GROWTH OF THIS DISTURBANCE. IT WILL BE INTERESTING TO SEE IF THE 
MODEL GUIDANCE IS CORRECT AND THIS DOES PAN OUT. IF IT DOES...IT 
WOULD BE AN EXCELLENT EXAMPLE OF HOW TROPICAL WAVES INTERACT 
WITH THE TOPOGRAPHY OF CENTRAL AMERICA AND THE MONSOON TROUGH TO 
HELP DEVELOP A TROPICAL SYSTEM IN THE EPAC.    

$$
AL