000
AXPZ20 KNHC 211522
TWDEP 

TROPICAL WEATHER DISCUSSION                                      
NWS NATIONAL HURRICANE CENTER MIAMI FL                           
1605 UTC FRI JUN 21 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 1200 UTC SURFACE ANALYSIS AND SATELLITE IMAGERY THROUGH 
1500 UTC.

...INTERTROPICAL CONVERGENCE ZONE/MONSOON TROUGH... 
           
MONSOON TROUGH AXIS EXTENDS FROM 09N84W TO 1007 MB LOW PRES NEAR 
13N100W TO 11N107W TO 1008 MB LOW PRES NEAR 12N116W TO 08N130W. 
ITCZ AXIS CONTINUES FROM 08N130W TO 08N140W. SCATTERED MODERATE 
ISOLATED STRONG CONVECTION IS FROM 07N TO 12N BETWEEN 85W AND 
96W...AND FROM 12N TO 15N BETWEEN 100W AND 105W. SCATTERED 
MODERATE CONVECTION CAN BE FOUND FROM 08N TO 11N BETWEEN 96W AND 
101W...AND FROM 11N TO 14N BETWEEN 110W AND 114W.

...DISCUSSION... 

ALOFT...SW TO W FLOW IS EVIDENT N OF 25N AHEAD OF AN UPPER LEVEL 
TROUGH LOCATED W OF THE FORECAST REGION. S OF THESE WINDS... 
BROAD ANTICYCLONIC FLOW IS NOTED BETWEEN 20N AND 25N ASSOCIATED 
WITH AN ANTICYCLONE CENTERED NEAR 23N120W. THE ASSOCIATED RIDGE 
EXTENDS EWD TO SOUTHERN BAJA CALIFORNIA. ANOTHER RIDGE EXTENDS 
FROM THE SAME ANTICYCLONE TO ABOUT 21N129W. AN UPPER LOW IS NEAR 
18N109W WITH A TROUGH STRETCHING MAINLY W TO NEAR 17N120W. 
THEN...AN INVERTED TROUGH IS LOCATED NEAR 125W S OF 16N. ANOTHER 
ANTICYCLONE IS LOCATED NEAR 12N108W. THE REMAINDER OF THE 
FORECAST AREA IS UNDER THE INFLUENCE OF NLY WINDS ALOFT...MAINLY 
E OF 100W. THESE WINDS ARE LIMITING THE DEVELOPMENT OF A LOW 
PRES EMBEDDED WITHIN THE MONSOON TROUGH NEAR 13N100W. ABUNDANT 
MID TO UPPER LEVEL MOISTURE IS NOTED ACROSS THE TROPICS S OF 17N 
E OF 120W.
   
AS PREVIOUSLY MENTIONED...A 1007 MB LOW PRES IS EMBEDDED WITHIN 
THE MONSOON TROUGH NEAR 13N100W. SCATTERED MODERATE TO STRONG 
CONVECTION IS OBSERVED WEST OF THE LOW CENTER FROM 12N TO 15N 
BETWEEN 100W AND 105W. FIRST-LIGHT VISIBLE IMAGERY SHOWS THAT 
THE CENTER IS VOID OF CONVECTION AND MOSTLY DEFINED BY A SWIRL 
OF LOW CLOUDS. COMPUTER MODELS DIFFER ON THE POSITION AND 
INTENSITY OF THIS SYSTEM BUT THE GENERAL CONSENSUS IS FOR THE 
LOW TO TRACK WESTWARD AND DEEPEN. CURRENTLY...THIS SYSTEM HAS A 
LOW CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 
HOURS DUE TO UNFAVORABLE ENVIRONMENTAL CONDITIONS.

A SECOND 1008 MB LOW PRES IS ALSO EMBEDDED WITHIN THE MONSOON 
TROUGH NEAR 12N116W. SCATTERED MODERATE CONVECTION IS NOTED 
WITHIN 90 NM SW QUADRANT OF LOW CENTER. THIS LOW IS EXPECTED TO 
MOVE NORTHWARD AND WILL LIKELY MERGE WITH THE EASTERMOST LOW IN 
ABOUT 48-72 HOURS. AS A RESULT...THIS SYSTEM HAS A VERY LOW 
CHANCE OF BECOMING A TROPICAL CYCLONE DURING THE NEXT 48 HOURS.

ELSEWHERE AT THE SURFACE...A 1028 MB SURFACE HIGH IS CENTERED 
NEAR 32N140W WITH A RIDGE EXTENDING SE TO 22N116W. E OF THE 
RIDGE THE NORTHERLY WINDS AT 20 KT ARE STILL OCCURRING AS FAR S 
AS 27N BETWEEN 118W-125W WITH SEAS TO 9 FT IN N SWELL. THE 
GRADIENT WILL CONTINUE TO SUPPORT 15-20 KT THROUGH THE WEEKEND. 
NE TRADES AREA ARE AT 15-20 KT SW OF THE RIDGE ACROSS THE WATERS 
W OF 130W WITH SEAS TO 9 FT IN NE SWELL. 

CROSS EQUATORIAL SW SWELL WITH LEADING EDGE PERIOD OF 16-17 
SECONDS DOMINATES MOST OF THE REGION E OF 120W WHILE N TO NE 
SWELL ARE AFFECTING THE REMAINDER OF THE FORECAST WATERS. 
ADDITIONAL PULSES OF CROSS EQUATORIAL SW SWELLS WILL CONTINUE TO 
SPREAD ACROSS THE WATERS E OF 110W THE REST OF TODAY AND SAT.
 
$$ 
GR