000
AXPZ20 KNHC 080901
TWDEP 

TROPICAL WEATHER DISCUSSION 
NWS NATIONAL HURRICANE CENTER MIAMI FL
1005 UTC SUN SEP 08 2013

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 0600 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0830 UTC.

...TROPICAL WAVES...

THE FAR SOUTHERN EXTENT OF A TROPICAL WAVE IS FORECAST TO MOVE 
ACROSS COSTA RICA AND HONDURAS THROUGH TODAY...EMERGING INTO THE 
PACIFIC WATERS NEAR THE GULF OF PAPAGAYO WITHIN THE NEXT 24 TO 
36 HOURS. ASSOCIATED CONVECTION IS DESCRIBED IN THE NEXT 
SECTION. WHILE THE TROPICAL WAVE MAY BECOME ILL-DEFINED THROUGH 
THE NEXT 48 HOURS...IT IS STILL EXPECTED TO HELP ENHANCE 
SOUTHERLY FLOW S OF THE MONSOON TROUGH WITH FRESH WINDS AND 8 FT 
SEAS EXPECTED FROM 09N TO 13N BETWEEN 99W AND 105W BY LATE MON 
NIGHT.
 
...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH...

THE MONSOON TROUGH AXIS EXTENDS FROM 11N86W TO 15N94W...THEN 
RESUMES FROM 18N109W TO 10N140W. NO ITCZ IS PRESENT E OF 140W. 
SCATTERED MODERATE CONVECTION IS N OF 11N E OF 89W...WITHIN 240 
NM S OF A LINE FROM 12N106W TO 14N113W TO 14N118W...AND FROM 11N 
TO 14N BETWEEN 120W AND 123W.

...DISCUSSION... 

A WEAKENING UPPER LEVEL ANTICYCLONE AT 25N131W IS BECOMING PART 
OF AN EXPANDING SECOND ANTICYCLONE CURRENTLY AT 23N114W...JUST 
SW OF THE SOUTHERN PORTION OF THE BAJA CALIFORNIA PENINSULA.  
BOTH ANTICYCLONES ARE MAINTAINING A VERY DRY SUBSIDING AIR MASS 
OVER THE NE PACIFIC WATERS NW OF A LINE FROM 25N112W TO 10N140W. 
THE EXPANDING ANTICYCLONIC CIRCULATION IS ALSO BRINGING 
CONVECTIVE DEBRIS FROM A DISSIPATING SURFACE TROUGH IN THE BAY 
OF CAMPECHE INTO THE NE PACIFIC.

1008 MB POST-TROPICAL REMNANT LOW LORENA IS NEAR 24.5N117.5W.    
A SMALL AREA OF DEEP CONVECTION HAS DEVELOPED WITHIN 60 NM IN 
THE S QUADRANT DURING THE PAST FEW HOURS...ALTHOUGH THIS WILL 
LIKELY BE SHORT LIVED. ASSOCIATED WINDS AND SEAS ARE FORECAST TO 
DIMINISH/SUBSIDE TO 20 KT OR LESS/LESS THAN 8 FT DURING THE NEXT 
06 HOURS...WHILE THE REMNANT CIRCULATION ITSELF DISSIPATES 
ALTOGETHER WITHIN THE NEXT 24 HOURS.

CROSS-EQUATORIAL SOUTHERLY SWELL WITH 8 TO 9 FT SEAS WILL PUSH 
AS FAR N AS 02N BETWEEN 105W AND 120W BY LATE MON NIGHT.

OTHERWISE...1024 MB HIGH PRES CENTERED WELL N OF THE BASIN NEAR 
41N136W EXTENDS A BROAD RIDGE THROUGH 32N135W TO 24N122W. A 
MAINLY FLAT PRES GRADIENT WILL BE MAINTAINED ACROSS THE 
REMAINDER OF THE WATERS WITH GENTLE TO MODERATE WINDS AND 4 TO 7 
FT SEAS...EXCEPT 2 TO 3 FT NEAR THE CENTRAL AMERICAN COAST. 

$$
LEWITSKY