000
AXPZ20 KNHC 220912
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN JUL 22 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 
0900 UTC.

...SPECIAL FEATURE...
LOW PRESSURE CENTER EMBEDDED IN THE MONSOON TROUGH NEAR 10N109W 
IS THE RESULT OF THE INTERACTION OF A TROPICAL WAVE AND THE 
MONSOON TROUGH. SCATTERED MODERATE ISOLATED STRONG CONVECTION 
WAS NOTED WITHIN 90 NM NW SEMICIRCLE OF THE LOW. BACKGROUND 
CONDITIONS ARE FAVORABLE FOR FURTHER DEVELOPMENT OF THIS FEATURE 
AND THERE IS CURRENTLY A MEDIUM CHANCE THAT THIS FEATURE WILL 
DEVELOP INTO A TROPICAL CYCLONE WITHIN THE NEXT 48 HOURS.    

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...
THE MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO A 1009 MB LOW 
PRES NEAR 08N95W TO 11N104W TO A 1009 MB LOW NEAR 10N109W TO 
08N112W TO 08N126W THEN ITCZ TO 10N135W TO BEYOND 08N140W. 
SCATTERED MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 
300 NM S OF MONSOON TROUGH AXIS BETWEEN 85W AND 93W. SCATTERED 
MODERATE ISOLATED STRONG CONVECTION WAS NOTED WITHIN 120 NM S OF 
MONSOON TROUGH AXIS BETWEEN 97W AND 103W.  

...DISCUSSION...
1029 MB HIGH PRESSURE CENTERED N OF THE FORECAST AREA NEAR 
37N142W EXTENDS A RIDGE SE TO NEAR 18N115W. THE PRESSURE 
GRADIENT BETWEEN THIS FEATURE AND LOWER PRES ALONG THE MONSOON 
TROUGH AND IN THE VICINITY OF THE ITCZ IS MAINTAINING FRESH 20 
KT WINDS FROM 10N TO 18N W OF 130W AND FROM 10N TO 15N BETWEEN 
120W AND 130W AS DEPICTED BY THE LATEST ASCAT PASS. THIS AREA OF 
TRADES WILL CONTINUE THROUGH THE FORECAST PERIOD. 

CROSS EQUATORIAL LONG PERIOD SW SWELLS OF 16-19 SECONDS ARE 
CURRENTLY IMPACTING THE COAST OF MEXICO...CENTRAL AMERICA AND 
BAJA CALIFORNIA...INCLUDING THE FAR S PORTION OF THE SEA OF 
CORTEZ. THE POTENTIAL FOR LARGE BREAKING WAVES AND DANGEROUS RIP 
CURRENTS WILL SLOWLY EBB THROUGH THE REMAINDER OF THE WEEKEND AS 
THE SWELL TRAIN SUBSIDES. 

FRESH GAP WINDS OF 20 KT CONTINUE ACROSS THE GULF OF PAPAGAYO. 
THE FORECAST CALLS FOR WINDS TO BECOME MORE DIURNALLY FORCED 
WITH 20 KT WINDS ONLY POSSIBLE DURING THE OVERNIGHT AND EARLY 
MORNING HOURS WITH THE AID OF THE DRAINAGE FLOW. 

FRESH GAP WINDS FUNNELING INTO THE GULF OF TEHUANTEPEC ARE AIDED 
BY A TROPICAL WAVE JUST EAST OF THE BAY OF CAMPECHE. WINDS 
FUNNELING THROUGH THE GAP ARE EXPECTED TO DIMINISH BELOW 20 KT 
BY MON MORNING AS THE TROPICAL WAVE MOVES WEST OF THE BAY OF 
CAMPECHE.  

$$
AL