000
AXPZ20 KNHC 270240
TWDEP 

TROPICAL WEATHER DISCUSSION
NWS NATIONAL HURRICANE CENTER MIAMI FL
0405 UTC FRI SEP 27 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 ON 0000 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
0230 UTC.

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

THE MONSOON TROUGH AXIS EXTENDS FROM 10N86W TO LOW PRES NEAR 
09N90W TO 09N100W...THEN RESUMES FROM LOW PRES NEAR 17N104W TO 
14N120W TO 11N140W. NO ITCZ IS PRESENT E OF 140W. SCATTERED 
MODERATE CONVECTION IS FROM 06N TO 09N BETWEEN 84W AND 88W... 
FROM 05N TO 07N BETWEEN 94W AND 97W...FROM 11N TO 15N BETWEEN 
115W AND 119W...AND ALSO FROM 10N TO 12N BETWEEN 119W AND 122W.

...DISCUSSION...

A BROAD UPPER LEVEL ANTICYCLONE IS CENTERED SW OF MEXICO NEAR 
19N109W. CONVECTIVE DEBRIS CONTINUES TO FAN OUT FROM SW MEXICO 
TO THE SW ACROSS THE NE PACIFIC WATERS FROM 10N TO 22N E OF 
120W. TO THE NW OF THE ANTICYCLONE...A FLATTENING UPPER LEVEL 
TROUGH REACHES INTO THE AREA JUST W OF THE BAJA CALIFORNIA 
PENINSULA. DRY AND STABLE AIR IS EVIDENT ON WATER VAPOR 
SATELLITE IMAGERY ACROSS THE WATERS N OF A LINE FROM THE 
SOUTHERN TIP OF THE BAJA CALIFORNIA PENINSULA TO 12N140W. 
PRIMARILY UPPER LEVEL EASTERLIES DOMINATE THE REMAINDER OF THE 
DISCUSSION WATERS ALOFT.

AT THE SURFACE...1030 MB HIGH PRES IS CENTERED WELL N OF THE 
DISCUSSION WATERS NEAR 40N138W WITH A RIDGE REACHING SE THROUGH 
32N128W TO 23N115W. MODERATE TO FRESH TRADES COVER THE WATERS N 
OF THE MONSOON TROUGH W OF 110W. NW SWELL WITH WAVE PERIODS OF 
13-16 SECONDS AND SEAS OF 8-11 FT COVER THE N CENTRAL WATERS. 
THIS SWELL WILL DECAY AS IT CONTINUES TO PROPAGATE TO THE SE-
S....SUBSIDING TO LESS THAN 8 FT BY SAT AFTERNOON.

1007 MB WEAK LOW PRES IS EMBEDDED IN THE MONSOON TROUGH NEAR 
09N90W. WINDS ARE ONLY LIGHT TO MODERATE NEAR THE LOW WITH SEAS 
LESS THAN 8 FT. CONVECTION IS ALSO DISORGANIZED AND LIMITED NEAR 
THE LOW. THIS LOW IS FORECAST TO MOVE W DURING THE NEXT 24-48 
HOURS WITH NO DEVELOPMENT EXPECTED.

ANOTHER 1007 MB LOW PRES AREA IS EMBEDDED IN THE MONSOON TROUGH 
SW OF MEXICO NEAR 17N104W. DISORGANIZED CONVECTION IS OCCURRING 
MAINLY W OF THE LOW AS WELL AS OVER SW MEXICO WHERE ADDITIONAL 
HEAVY RAINFALL CONTINUES WITH THE LINGERING THREAT OF LOCALIZED 
FLASH FLOODING AND MUDSLIDES. THIS LOW IS FORECAST TO MOVE SW-W 
DURING THE NEXT 24-48 HOURS WITH LIMITED DEVELOPMENT EXPECTED.

CROSS-EQUATORIAL SE SWELL MIXING WITH THE ABOVE DESCRIBED NW 
SWELL IS BUILDING SEAS UP TO 8-9 FT OVER THE SW WATERS. THIS 
SWELL WILL GRADUALLY DECAY THROUGH THE NEXT 48 HOURS...WITH A 
REMNANT AREA OF 8-9 FT SWELL SHIFTING NE WHILE BECOMING 
PRIMARILY NW SWELL BY SAT AFTERNOON.
 
$$
LEWITSKY